Merge branch 'develop' into mongodb-3.4mongodb-3.4.0-rc1

85 files changed, 2113 insertions, 1887 deletions

diff --git a/bench/wtperf/config.c b/bench/wtperf/config.c
index 4c7b17f102a..5b14a4cdf68 100644
--- a/bench/wtperf/config.c
+++ b/bench/wtperf/config.c
@@ -28,15 +28,19 @@
 
 #include "wtperf.h"
 
-/* All options changeable on command line using -o or -O are listed here. */
-static CONFIG_OPT config_opts[] = {
+static CONFIG_OPT config_opts_desc[] = {	/* Option descriptions */
 #define	OPT_DEFINE_DESC
 #include "wtperf_opt.i"
 #undef OPT_DEFINE_DESC
 };
 
-static int  config_opt(CONFIG *, WT_CONFIG_ITEM *, WT_CONFIG_ITEM *);
-static void config_opt_usage(void);
+static CONFIG_OPTS config_opts_default = {	/* Option defaults */
+#define	OPT_DEFINE_DEFAULT
+#include "wtperf_opt.i"
+#undef OPT_DEFINE_DEFAULT
+
+	{ NULL, NULL }				/* config_head */
+};
 
 /*
  * STRING_MATCH --
@@ -47,6 +51,72 @@ static void config_opt_usage(void);
 	(strncmp(str, bytes, len) == 0 && (str)[(len)] == '\0')
 
 /*
+ * config_opt_init --
+ *	Initialize the global configuration options.
+ */
+void
+config_opt_init(CONFIG_OPTS **retp)
+{
+	CONFIG_OPT *desc;
+	CONFIG_OPTS *opts;
+	size_t i;
+	char **strp;
+	void *valueloc;
+
+	opts = dmalloc(sizeof(CONFIG_OPTS));
+	*opts = config_opts_default;
+
+	TAILQ_INIT(&opts->config_head);
+
+	/*
+	 * Option strings come-and-go as we configure them, so allocate copies
+	 * of the default strings now so that we can always free the string as
+	 * we allocate new versions.
+	 */
+	for (i = 0, desc = config_opts_desc;
+	    i < WT_ELEMENTS(config_opts_desc); i++, ++desc)
+		if (desc->type == CONFIG_STRING_TYPE ||
+		    desc->type == STRING_TYPE) {
+			valueloc = ((uint8_t *)opts + desc->offset);
+			strp = (char **)valueloc;
+			*strp = dstrdup(*strp);
+		}
+
+	*retp = opts;
+}
+
+/*
+ * config_opt_cleanup --
+ *	Clean up the global configuration options.
+ */
+void
+config_opt_cleanup(CONFIG_OPTS *opts)
+{
+	CONFIG_OPT *desc;
+	CONFIG_QUEUE_ENTRY *config_line;
+	size_t i;
+	char **strp;
+	void *valueloc;
+
+	for (i = 0, desc = config_opts_desc;
+	    i < WT_ELEMENTS(config_opts_desc); i++, ++desc)
+		if (desc->type == CONFIG_STRING_TYPE ||
+		    desc->type == STRING_TYPE) {
+			valueloc = ((uint8_t *)opts + desc->offset);
+			strp = (char **)valueloc;
+			free(*strp);
+		}
+
+	while ((config_line = TAILQ_FIRST(&opts->config_head)) != NULL) {
+		TAILQ_REMOVE(&opts->config_head, config_line, q);
+		free(config_line->string);
+		free(config_line);
+	}
+
+	free(opts);
+}
+
+/*
  * config_unescape --
  *	Modify a string in place, replacing any backslash escape sequences.
  *	The modified string is always shorter.
@@ -94,168 +164,11 @@ config_unescape(char *orig)
 }
 
 /*
- * config_copy --
- *	CONFIG structure initialization, based on a source configuration.
- */
-void
-config_copy(CONFIG *dest, const CONFIG *src)
-{
-	CONFIG_QUEUE_ENTRY *conf_line, *tmp_line;
-	size_t i;
-	char *newstr, **pstr;
-
-	memcpy(dest, src, sizeof(CONFIG));
-
-	if (src->home != NULL)
-		dest->home = dstrdup(src->home);
-	if (src->monitor_dir != NULL)
-		dest->monitor_dir = dstrdup(src->monitor_dir);
-	if (src->partial_config != NULL)
-		dest->partial_config = dstrdup(src->partial_config);
-	if (src->reopen_config != NULL)
-		dest->reopen_config = dstrdup(src->reopen_config);
-	if (src->base_uri != NULL)
-		dest->base_uri = dstrdup(src->base_uri);
-
-	if (src->uris != NULL) {
-		dest->uris = dcalloc(src->table_count, sizeof(char *));
-		for (i = 0; i < src->table_count; i++)
-			dest->uris[i] = dstrdup(src->uris[i]);
-	}
-
-	if (src->async_config != NULL)
-		dest->async_config = dstrdup(src->async_config);
-
-	dest->ckptthreads = NULL;
-	dest->popthreads = NULL;
-	dest->workers = NULL;
-
-	if (src->workload != NULL) {
-		dest->workload = dcalloc(WORKLOAD_MAX, sizeof(WORKLOAD));
-		memcpy(dest->workload,
-		    src->workload, WORKLOAD_MAX * sizeof(WORKLOAD));
-	}
-
-	for (i = 0; i < sizeof(config_opts) / sizeof(config_opts[0]); i++)
-		if (config_opts[i].type == STRING_TYPE ||
-		    config_opts[i].type == CONFIG_STRING_TYPE) {
-			pstr = (char **)
-			    ((u_char *)dest + config_opts[i].offset);
-			if (*pstr != NULL) {
-				newstr = dstrdup(*pstr);
-				*pstr = newstr;
-			}
-		}
-
-	TAILQ_INIT(&dest->stone_head);
-	TAILQ_INIT(&dest->config_head);
-
-	/* Clone the config string information into the new cfg object */
-	TAILQ_FOREACH(conf_line, &src->config_head, c) {
-		tmp_line = dcalloc(sizeof(CONFIG_QUEUE_ENTRY), 1);
-		tmp_line->string = dstrdup(conf_line->string);
-		TAILQ_INSERT_TAIL(&dest->config_head, tmp_line, c);
-	}
-}
-
-/*
- * config_free --
- *	Free any storage allocated in the config struct.
- */
-void
-config_free(CONFIG *cfg)
-{
-	CONFIG_QUEUE_ENTRY *config_line;
-	size_t i;
-	char **pstr;
-
-	free(cfg->home);
-	free(cfg->monitor_dir);
-	free(cfg->partial_config);
-	free(cfg->reopen_config);
-
-	/* Free the various URIs */
-	free(cfg->base_uri);
-	free(cfg->log_table_uri);
-
-	if (cfg->uris != NULL) {
-		for (i = 0; i < cfg->table_count; i++)
-			free(cfg->uris[i]);
-		free(cfg->uris);
-	}
-
-	free(cfg->async_config);
-
-	free(cfg->ckptthreads);
-	free(cfg->popthreads);
-
-	free(cfg->workers);
-	free(cfg->workload);
-
-	cleanup_truncate_config(cfg);
-
-	while (!TAILQ_EMPTY(&cfg->config_head)) {
-		config_line = TAILQ_FIRST(&cfg->config_head);
-		TAILQ_REMOVE(&cfg->config_head, config_line, c);
-		free(config_line->string);
-		free(config_line);
-	}
-
-	for (i = 0; i < sizeof(config_opts) / sizeof(config_opts[0]); i++)
-		if (config_opts[i].type == STRING_TYPE ||
-		    config_opts[i].type == CONFIG_STRING_TYPE) {
-			pstr = (char **)
-			    ((u_char *)cfg + config_opts[i].offset);
-			free(*pstr);
-			*pstr = NULL;
-		}
-}
-
-/*
- * config_compress --
- *	Parse the compression configuration.
- */
-int
-config_compress(CONFIG *cfg)
-{
-	int ret;
-	const char *s;
-
-	ret = 0;
-	s = cfg->compression;
-	if (strcmp(s, "none") == 0) {
-		cfg->compress_ext = NULL;
-		cfg->compress_table = NULL;
-	} else if (strcmp(s, "lz4") == 0) {
-#ifndef HAVE_BUILTIN_EXTENSION_LZ4
-		cfg->compress_ext = LZ4_EXT;
-#endif
-		cfg->compress_table = LZ4_BLK;
-	} else if (strcmp(s, "snappy") == 0) {
-#ifndef HAVE_BUILTIN_EXTENSION_SNAPPY
-		cfg->compress_ext = SNAPPY_EXT;
-#endif
-		cfg->compress_table = SNAPPY_BLK;
-	} else if (strcmp(s, "zlib") == 0) {
-#ifndef HAVE_BUILTIN_EXTENSION_ZLIB
-		cfg->compress_ext = ZLIB_EXT;
-#endif
-		cfg->compress_table = ZLIB_BLK;
-	} else {
-		fprintf(stderr,
-	    "invalid compression configuration: %s\n", s);
-		ret = EINVAL;
-	}
-	return (ret);
-
-}
-
-/*
  * config_threads --
  *	Parse the thread configuration.
  */
 static int
-config_threads(CONFIG *cfg, const char *config, size_t len)
+config_threads(WTPERF *wtperf, const char *config, size_t len)
 {
 	WORKLOAD *workp;
 	WT_CONFIG_ITEM groupk, groupv, k, v;
@@ -263,19 +176,19 @@ config_threads(CONFIG *cfg, const char *config, size_t len)
 	int ret;
 
 	group = scan = NULL;
-	if (cfg->workload != NULL) {
+	if (wtperf->workload != NULL) {
 		/*
 		 * This call overrides an earlier call.  Free and
 		 * reset everything.
 		 */
-		free(cfg->workload);
-		cfg->workload = NULL;
-		cfg->workload_cnt = 0;
-		cfg->workers_cnt = 0;
+		free(wtperf->workload);
+		wtperf->workload = NULL;
+		wtperf->workload_cnt = 0;
+		wtperf->workers_cnt = 0;
 	}
 	/* Allocate the workload array. */
-	cfg->workload = dcalloc(WORKLOAD_MAX, sizeof(WORKLOAD));
-	cfg->workload_cnt = 0;
+	wtperf->workload = dcalloc(WORKLOAD_MAX, sizeof(WORKLOAD));
+	wtperf->workload_cnt = 0;
 
 	/*
 	 * The thread configuration may be in multiple groups, that is, we have
@@ -294,14 +207,14 @@ config_threads(CONFIG *cfg, const char *config, size_t len)
 			goto err;
 
 		/* Move to the next workload slot. */
-		if (cfg->workload_cnt == WORKLOAD_MAX) {
+		if (wtperf->workload_cnt == WORKLOAD_MAX) {
 			fprintf(stderr,
 			    "too many workloads configured, only %d workloads "
 			    "supported\n",
 			    WORKLOAD_MAX);
 			return (EINVAL);
 		}
-		workp = &cfg->workload[cfg->workload_cnt++];
+		workp = &wtperf->workload[wtperf->workload_cnt++];
 
 		while ((ret = scan->next(scan, &k, &v)) == 0) {
 			if (STRING_MATCH("count", k.str, k.len)) {
@@ -334,9 +247,9 @@ config_threads(CONFIG *cfg, const char *config, size_t len)
 				if ((workp->truncate = v.val) != 1)
 					goto err;
 				/* There can only be one Truncate thread. */
-				if (F_ISSET(cfg, CFG_TRUNCATE))
+				if (F_ISSET(wtperf, CFG_TRUNCATE))
 					goto err;
-				F_SET(cfg, CFG_TRUNCATE);
+				F_SET(wtperf, CFG_TRUNCATE);
 				continue;
 			}
 			if (STRING_MATCH("truncate_pct", k.str, k.len)) {
@@ -364,13 +277,13 @@ config_threads(CONFIG *cfg, const char *config, size_t len)
 						goto err;
 					/* Special random value */
 					workp->update_delta = INT64_MAX;
-					F_SET(cfg, CFG_GROW);
+					F_SET(wtperf, CFG_GROW);
 				} else {
 					workp->update_delta = v.val;
 					if (v.val > 0)
-						F_SET(cfg, CFG_GROW);
+						F_SET(wtperf, CFG_GROW);
 					if (v.val < 0)
-						F_SET(cfg, CFG_SHRINK);
+						F_SET(wtperf, CFG_SHRINK);
 				}
 				continue;
 			}
@@ -400,7 +313,7 @@ config_threads(CONFIG *cfg, const char *config, size_t len)
 		if (workp->truncate != 0 &&
 		    (workp->insert > 0 || workp->read > 0 || workp->update > 0))
 			goto err;
-		cfg->workers_cnt += (u_int)workp->threads;
+		wtperf->workers_cnt += (u_int)workp->threads;
 	}
 
 	ret = group->close(group);
@@ -428,32 +341,34 @@ err:	if (group != NULL)
  * value.
  */
 static int
-config_opt(CONFIG *cfg, WT_CONFIG_ITEM *k, WT_CONFIG_ITEM *v)
+config_opt(WTPERF *wtperf, WT_CONFIG_ITEM *k, WT_CONFIG_ITEM *v)
 {
-	CONFIG_OPT *popt;
+	CONFIG_OPTS *opts;
+	CONFIG_OPT *desc;
 	char *begin, *newstr, **strp;
 	int ret;
-	size_t i, newlen, nopt;
+	size_t i, newlen;
 	void *valueloc;
 
-	popt = NULL;
-	nopt = sizeof(config_opts)/sizeof(config_opts[0]);
-	for (i = 0; i < nopt; i++)
-		if (strlen(config_opts[i].name) == k->len &&
-		    strncmp(config_opts[i].name, k->str, k->len) == 0) {
-			popt = &config_opts[i];
+	opts = wtperf->opts;
+
+	desc = NULL;
+	for (i = 0; i < WT_ELEMENTS(config_opts_desc); i++)
+		if (strlen(config_opts_desc[i].name) == k->len &&
+		    strncmp(config_opts_desc[i].name, k->str, k->len) == 0) {
+			desc = &config_opts_desc[i];
 			break;
 		}
-	if (popt == NULL) {
+	if (desc == NULL) {
 		fprintf(stderr, "wtperf: Error: "
 		    "unknown option \'%.*s\'\n", (int)k->len, k->str);
 		fprintf(stderr, "Options:\n");
-		for (i = 0; i < nopt; i++)
-			fprintf(stderr, "\t%s\n", config_opts[i].name);
+		for (i = 0; i < WT_ELEMENTS(config_opts_desc); i++)
+			fprintf(stderr, "\t%s\n", config_opts_desc[i].name);
 		return (EINVAL);
 	}
-	valueloc = ((u_char *)cfg + popt->offset);
-	switch (popt->type) {
+	valueloc = ((uint8_t *)opts + desc->offset);
+	switch (desc->type) {
 	case BOOL_TYPE:
 		if (v->type != WT_CONFIG_ITEM_BOOL) {
 			fprintf(stderr, "wtperf: Error: "
@@ -531,7 +446,7 @@ config_opt(CONFIG *cfg, WT_CONFIG_ITEM *k, WT_CONFIG_ITEM *v)
 		 */
 		if (v->type == WT_CONFIG_ITEM_STRUCT &&
 		    STRING_MATCH("threads", k->str, k->len))
-			return (config_threads(cfg, v->str, v->len));
+			return (config_threads(wtperf, v->str, v->len));
 
 		if (v->type != WT_CONFIG_ITEM_STRING &&
 		    v->type != WT_CONFIG_ITEM_ID) {
@@ -559,7 +474,7 @@ config_opt(CONFIG *cfg, WT_CONFIG_ITEM *k, WT_CONFIG_ITEM *v)
  * via lines ending in '\'.
  */
 int
-config_opt_file(CONFIG *cfg, const char *filename)
+config_opt_file(WTPERF *wtperf, const char *filename)
 {
 	FILE *fp;
 	size_t linelen, optionpos;
@@ -659,7 +574,7 @@ config_opt_file(CONFIG *cfg, const char *filename)
 		if (contline)
 			optionpos += linelen;
 		else {
-			if ((ret = config_opt_line(cfg, option)) != 0) {
+			if ((ret = config_opt_str(wtperf, option)) != 0) {
 				fprintf(stderr, "wtperf: %s: %d: parse error\n",
 				    filename, linenum);
 				break;
@@ -684,23 +599,26 @@ config_opt_file(CONFIG *cfg, const char *filename)
 }
 
 /*
- * config_opt_line --
+ * config_opt_str --
  *	Parse a single line of config options.  Continued lines have already
  * been joined.
  */
 int
-config_opt_line(CONFIG *cfg, const char *optstr)
+config_opt_str(WTPERF *wtperf, const char *optstr)
 {
+	CONFIG_OPTS *opts;
 	CONFIG_QUEUE_ENTRY *config_line;
 	WT_CONFIG_ITEM k, v;
 	WT_CONFIG_PARSER *scan;
 	size_t len;
 	int ret, t_ret;
 
+	opts = wtperf->opts;
+
 	len = strlen(optstr);
 	if ((ret = wiredtiger_config_parser_open(
 	    NULL, optstr, len, &scan)) != 0) {
-		lprintf(cfg, ret, 0, "Error in config_scan_begin");
+		lprintf(wtperf, ret, 0, "Error in config_scan_begin");
 		return (ret);
 	}
 
@@ -712,7 +630,7 @@ config_opt_line(CONFIG *cfg, const char *optstr)
 	 */
 	config_line = dcalloc(sizeof(CONFIG_QUEUE_ENTRY), 1);
 	config_line->string = dstrdup(optstr);
-	TAILQ_INSERT_TAIL(&cfg->config_head, config_line, c);
+	TAILQ_INSERT_TAIL(&opts->config_head, config_line, q);
 
 	while (ret == 0) {
 		if ((ret = scan->next(scan, &k, &v)) != 0) {
@@ -721,10 +639,10 @@ config_opt_line(CONFIG *cfg, const char *optstr)
 				ret = 0;
 			break;
 		}
-		ret = config_opt(cfg, &k, &v);
+		ret = config_opt(wtperf, &k, &v);
 	}
 	if ((t_ret = scan->close(scan)) != 0) {
-		lprintf(cfg, ret, 0, "Error in config_scan_end");
+		lprintf(wtperf, ret, 0, "Error in config_scan_end");
 		if (ret == 0)
 			ret = t_ret;
 	}
@@ -733,19 +651,20 @@ config_opt_line(CONFIG *cfg, const char *optstr)
 }
 
 /*
- * config_opt_str --
- *	Set a single string config option.
+ * config_opt_name_value --
+ *	Set a name/value configuration pair.
  */
 int
-config_opt_str(CONFIG *cfg, const char *name, const char *value)
+config_opt_name_value(WTPERF *wtperf, const char *name, const char *value)
 {
+	size_t len;
 	int ret;
 	char *optstr;
-
 							/* name="value" */
-	optstr = dmalloc(strlen(name) + strlen(value) + 4);
-	sprintf(optstr, "%s=\"%s\"", name, value);
-	ret = config_opt_line(cfg, optstr);
+	len = strlen(name) + strlen(value) + 4;
+	optstr = dmalloc(len);
+	snprintf(optstr, len, "%s=\"%s\"", name, value);
+	ret = config_opt_str(wtperf, optstr);
 	free(optstr);
 	return (ret);
 }
@@ -755,60 +674,63 @@ config_opt_str(CONFIG *cfg, const char *name, const char *value)
  *	Configuration sanity checks.
  */
 int
-config_sanity(CONFIG *cfg)
+config_sanity(WTPERF *wtperf)
 {
+	CONFIG_OPTS *opts;
 	WORKLOAD *workp;
 	u_int i;
 
+	opts = wtperf->opts;
+
 	/* Various intervals should be less than the run-time. */
-	if (cfg->run_time > 0 &&
-	    ((cfg->checkpoint_threads != 0 &&
-	    cfg->checkpoint_interval > cfg->run_time) ||
-	    cfg->report_interval > cfg->run_time ||
-	    cfg->sample_interval > cfg->run_time)) {
+	if (opts->run_time > 0 &&
+	    ((opts->checkpoint_threads != 0 &&
+	    opts->checkpoint_interval > opts->run_time) ||
+	    opts->report_interval > opts->run_time ||
+	    opts->sample_interval > opts->run_time)) {
 		fprintf(stderr, "interval value longer than the run-time\n");
 		return (EINVAL);
 	}
 	/* The maximum is here to keep file name construction simple. */
-	if (cfg->table_count < 1 || cfg->table_count > 99999) {
+	if (opts->table_count < 1 || opts->table_count > 99999) {
 		fprintf(stderr,
 		    "invalid table count, less than 1 or greater than 99999\n");
 		return (EINVAL);
 	}
-	if (cfg->database_count < 1 || cfg->database_count > 99) {
+	if (opts->database_count < 1 || opts->database_count > 99) {
 		fprintf(stderr,
 		    "invalid database count, less than 1 or greater than 99\n");
 		return (EINVAL);
 	}
 
-	if (cfg->pareto > 100) {
+	if (opts->pareto > 100) {
 		fprintf(stderr,
 		    "Invalid pareto distribution - should be a percentage\n");
 		return (EINVAL);
 	}
 
-	if (cfg->value_sz_max < cfg->value_sz) {
-		if (F_ISSET(cfg, CFG_GROW)) {
+	if (opts->value_sz_max < opts->value_sz) {
+		if (F_ISSET(wtperf, CFG_GROW)) {
 			fprintf(stderr, "value_sz_max %" PRIu32
 			    " must be greater than or equal to value_sz %"
-			    PRIu32 "\n", cfg->value_sz_max, cfg->value_sz);
+			    PRIu32 "\n", opts->value_sz_max, opts->value_sz);
 			return (EINVAL);
 		} else
-			cfg->value_sz_max = cfg->value_sz;
+			opts->value_sz_max = opts->value_sz;
 	}
-	if (cfg->value_sz_min > cfg->value_sz) {
-		if (F_ISSET(cfg, CFG_SHRINK)) {
+	if (opts->value_sz_min > opts->value_sz) {
+		if (F_ISSET(wtperf, CFG_SHRINK)) {
 			fprintf(stderr, "value_sz_min %" PRIu32
 			    " must be less than or equal to value_sz %"
-			    PRIu32 "\n", cfg->value_sz_min, cfg->value_sz);
+			    PRIu32 "\n", opts->value_sz_min, opts->value_sz);
 			return (EINVAL);
 		} else
-			cfg->value_sz_min = cfg->value_sz;
+			opts->value_sz_min = opts->value_sz;
 	}
 
-	if (cfg->readonly && cfg->workload != NULL)
-		for (i = 0, workp = cfg->workload;
-		    i < cfg->workload_cnt; ++i, ++workp)
+	if (opts->readonly && wtperf->workload != NULL)
+		for (i = 0, workp = wtperf->workload;
+		    i < wtperf->workload_cnt; ++i, ++workp)
 			if (workp->insert != 0 || workp->update != 0 ||
 			    workp->truncate != 0) {
 				fprintf(stderr,
@@ -824,21 +746,21 @@ config_sanity(CONFIG *cfg)
  *	Consolidate repeated configuration settings so that it only appears
  *	once in the configuration output file.
  */
-void
-config_consolidate(CONFIG *cfg)
+static void
+config_consolidate(CONFIG_OPTS *opts)
 {
 	CONFIG_QUEUE_ENTRY *conf_line, *test_line, *tmp;
 	char *string_key;
 
 	/*
-	 * This loop iterates over the config queue and for entry checks if an
-	 * entry later in the queue has the same key. If a match is found then
-	 * the current queue entry is removed and we continue.
+	 * This loop iterates over the config queue and for each entry checks if
+	 * a later queue entry has the same key. If there's a match, the current
+	 * queue entry is removed and we continue.
 	 */
-	conf_line = TAILQ_FIRST(&cfg->config_head);
+	conf_line = TAILQ_FIRST(&opts->config_head);
 	while (conf_line != NULL) {
 		string_key = strchr(conf_line->string, '=');
-		tmp = test_line = TAILQ_NEXT(conf_line, c);
+		tmp = test_line = TAILQ_NEXT(conf_line, q);
 		while (test_line != NULL) {
 			/*
 			 * The + 1 here forces the '=' sign to be matched
@@ -849,89 +771,75 @@ config_consolidate(CONFIG *cfg)
 			if (strncmp(conf_line->string, test_line->string,
 			    (size_t)((string_key - conf_line->string) + 1))
 			    == 0) {
-				TAILQ_REMOVE(&cfg->config_head, conf_line, c);
+				TAILQ_REMOVE(&opts->config_head, conf_line, q);
 				free(conf_line->string);
 				free(conf_line);
 				break;
 			}
-			test_line = TAILQ_NEXT(test_line, c);
+			test_line = TAILQ_NEXT(test_line, q);
 		}
 		conf_line = tmp;
 	}
 }
 
 /*
- * config_to_file --
+ * config_opt_log --
  *	Write the final config used in this execution to a file.
  */
 void
-config_to_file(CONFIG *cfg)
+config_opt_log(CONFIG_OPTS *opts, const char *path)
 {
 	CONFIG_QUEUE_ENTRY *config_line;
 	FILE *fp;
-	size_t req_len;
-	char *path;
 
-	fp = NULL;
+	testutil_checkfmt(((fp = fopen(path, "w")) == NULL), "%s", path);
 
-	/* Backup the config */
-	req_len = strlen(cfg->home) + strlen("/CONFIG.wtperf") + 1;
-	path = dcalloc(req_len, 1);
-	snprintf(path, req_len, "%s/CONFIG.wtperf", cfg->home);
-	if ((fp = fopen(path, "w")) == NULL) {
-		lprintf(cfg, errno, 0, "%s", path);
-		goto err;
-	}
+	config_consolidate(opts);
 
-	/* Print the config dump */
-	fprintf(fp,"# Warning. This config includes "
+	fprintf(fp,"# Warning: This config includes "
 	    "unwritten, implicit configuration defaults.\n"
 	    "# Changes to those values may cause differences in behavior.\n");
-	config_consolidate(cfg);
-	config_line = TAILQ_FIRST(&cfg->config_head);
-	while (config_line != NULL) {
+	TAILQ_FOREACH(config_line, &opts->config_head, q)
 		fprintf(fp, "%s\n", config_line->string);
-		config_line = TAILQ_NEXT(config_line, c);
-	}
-
-err:	free(path);
-	if (fp != NULL)
-		(void)fclose(fp);
+	testutil_check(fclose(fp));
 }
 
 /*
- * config_print --
+ * config_opt_print --
  *	Print out the configuration in verbose mode.
  */
 void
-config_print(CONFIG *cfg)
+config_opt_print(WTPERF *wtperf)
 {
+	CONFIG_OPTS *opts;
 	WORKLOAD *workp;
 	u_int i;
 
+	opts = wtperf->opts;
+
 	printf("Workload configuration:\n");
-	printf("\t" "Home: %s\n", cfg->home);
-	printf("\t" "Table name: %s\n", cfg->table_name);
-	printf("\t" "Connection configuration: %s\n", cfg->conn_config);
-	if (cfg->sess_config != NULL)
-		printf("\t" "Session configuration: %s\n", cfg->sess_config);
+	printf("\t" "Home: %s\n", wtperf->home);
+	printf("\t" "Table name: %s\n", opts->table_name);
+	printf("\t" "Connection configuration: %s\n", opts->conn_config);
+	if (opts->sess_config != NULL)
+		printf("\t" "Session configuration: %s\n", opts->sess_config);
 
 	printf("\t%s table: %s\n",
-	    cfg->create ? "Creating new" : "Using existing",
-	    cfg->table_config);
+	    opts->create ? "Creating new" : "Using existing",
+	    opts->table_config);
 	printf("\t" "Key size: %" PRIu32 ", value size: %" PRIu32 "\n",
-	    cfg->key_sz, cfg->value_sz);
-	if (cfg->create)
+	    opts->key_sz, opts->value_sz);
+	if (opts->create)
 		printf("\t" "Populate threads: %" PRIu32 ", inserting %" PRIu32
 		    " rows\n",
-		    cfg->populate_threads, cfg->icount);
+		    opts->populate_threads, opts->icount);
 
 	printf("\t" "Workload seconds, operations: %" PRIu32 ", %" PRIu32 "\n",
-	    cfg->run_time, cfg->run_ops);
-	if (cfg->workload != NULL) {
+	    opts->run_time, opts->run_ops);
+	if (wtperf->workload != NULL) {
 		printf("\t" "Workload configuration(s):\n");
-		for (i = 0, workp = cfg->workload;
-		    i < cfg->workload_cnt; ++i, ++workp)
+		for (i = 0, workp = wtperf->workload;
+		    i < wtperf->workload_cnt; ++i, ++workp)
 			printf("\t\t%" PRId64 " threads (inserts=%" PRId64
 			    ", reads=%" PRId64 ", updates=%" PRId64
 			    ", truncates=% " PRId64 ")\n",
@@ -941,11 +849,11 @@ config_print(CONFIG *cfg)
 	}
 
 	printf("\t" "Checkpoint threads, interval: %" PRIu32 ", %" PRIu32 "\n",
-	    cfg->checkpoint_threads, cfg->checkpoint_interval);
-	printf("\t" "Reporting interval: %" PRIu32 "\n", cfg->report_interval);
-	printf("\t" "Sampling interval: %" PRIu32 "\n", cfg->sample_interval);
+	    opts->checkpoint_threads, opts->checkpoint_interval);
+	printf("\t" "Reporting interval: %" PRIu32 "\n", opts->report_interval);
+	printf("\t" "Sampling interval: %" PRIu32 "\n", opts->sample_interval);
 
-	printf("\t" "Verbosity: %" PRIu32 "\n", cfg->verbose);
+	printf("\t" "Verbosity: %" PRIu32 "\n", opts->verbose);
 }
 
 /*
@@ -975,10 +883,10 @@ pretty_print(const char *p, const char *indent)
  * config_opt_usage --
  *	Configuration usage error message.
  */
-static void
+void
 config_opt_usage(void)
 {
-	size_t i, nopt;
+	size_t i;
 	const char *defaultval, *typestr;
 
 	pretty_print(
@@ -988,11 +896,10 @@ config_opt_usage(void)
 	    "String values must be enclosed in \" quotes, boolean values must "
 	    "be either true or false.\n", NULL);
 
-	nopt = sizeof(config_opts)/sizeof(config_opts[0]);
-	for (i = 0; i < nopt; i++) {
-		defaultval = config_opts[i].defaultval;
+	for (i = 0; i < WT_ELEMENTS(config_opts_desc); i++) {
+		defaultval = config_opts_desc[i].defaultval;
 		typestr = "string";
-		switch (config_opts[i].type) {
+		switch (config_opts_desc[i].type) {
 		case BOOL_TYPE:
 			typestr = "boolean";
 			if (strcmp(defaultval, "0") == 0)
@@ -1011,28 +918,7 @@ config_opt_usage(void)
 			break;
 		}
 		printf("%s (%s, default=%s)\n",
-		    config_opts[i].name, typestr, defaultval);
-		pretty_print(config_opts[i].description, "\t");
+		    config_opts_desc[i].name, typestr, defaultval);
+		pretty_print(config_opts_desc[i].description, "\t");
 	}
 }
-
-/*
- * usage --
- *	wtperf usage print, no error.
- */
-void
-usage(void)
-{
-	printf("wtperf [-C config] "
-	    "[-H mount] [-h home] [-O file] [-o option] [-T config]\n");
-	printf("\t-C <string> additional connection configuration\n");
-	printf("\t            (added to option conn_config)\n");
-	printf("\t-H <mount> configure Helium volume mount point\n");
-	printf("\t-h <string> Wired Tiger home must exist, default WT_TEST\n");
-	printf("\t-O <file> file contains options as listed below\n");
-	printf("\t-o option=val[,option=val,...] set options listed below\n");
-	printf("\t-T <string> additional table configuration\n");
-	printf("\t            (added to option table_config)\n");
-	printf("\n");
-	config_opt_usage();
-}
diff --git a/bench/wtperf/config_opt.h b/bench/wtperf/config_opt.h
index b7eff8e143f..3f1ab642227 100644
--- a/bench/wtperf/config_opt.h
+++ b/bench/wtperf/config_opt.h
@@ -37,3 +37,17 @@ typedef struct {
 	CONFIG_OPT_TYPE type;
 	size_t offset;
 } CONFIG_OPT;
+
+typedef struct __config_queue_entry {
+	char *string;
+	TAILQ_ENTRY(__config_queue_entry) q;
+} CONFIG_QUEUE_ENTRY;
+
+typedef struct {					/* Option structure */
+#define	OPT_DECLARE_STRUCT
+#include "wtperf_opt.i"
+#undef	OPT_DECLARE_STRUCT
+
+	/* Queue head to save a copy of the config to be output */
+	TAILQ_HEAD(__config_qh, __config_queue_entry) config_head;
+} CONFIG_OPTS;
diff --git a/bench/wtperf/doxy.c b/bench/wtperf/doxy.c
deleted file mode 100644
index 26d73168ef2..00000000000
--- a/bench/wtperf/doxy.c
+++ /dev/null
@@ -1,111 +0,0 @@
-/*-
- * Public Domain 2014-2016 MongoDB, Inc.
- * Public Domain 2008-2014 WiredTiger, Inc.
- *
- * This is free and unencumbered software released into the public domain.
- *
- * Anyone is free to copy, modify, publish, use, compile, sell, or
- * distribute this software, either in source code form or as a compiled
- * binary, for any purpose, commercial or non-commercial, and by any
- * means.
- *
- * In jurisdictions that recognize copyright laws, the author or authors
- * of this software dedicate any and all copyright interest in the
- * software to the public domain. We make this dedication for the benefit
- * of the public at large and to the detriment of our heirs and
- * successors. We intend this dedication to be an overt act of
- * relinquishment in perpetuity of all present and future rights to this
- * software under copyright law.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
- * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
- * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
- * IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR
- * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
- * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
- * OTHER DEALINGS IN THE SOFTWARE.
- */
-
-#include <string.h>
-#include <stdio.h>
-
-#include "config_opt.h"
-
-static const CONFIG_OPT config_opts[] = {
-#define	OPT_DEFINE_DOXYGEN
-#include "wtperf_opt.i"
-#undef	OPT_DEFINE_DOXYGEN
-};
-
-/*
- * pretty_print --
- *	Print out lines of text for a 80 character window.
- */
-static void
-pretty_print(const char *p, const char *indent)
-{
-	const char *t;
-
-	for (;; p = t + 1) {
-		if (strlen(p) <= 70)
-			break;
-		for (t = p + 70; t > p && *t != ' '; --t)
-			;
-		if (t == p)			/* No spaces? */
-			break;
-		printf("%s%.*s\n",
-		    indent == NULL ? "" : indent, (int)(t - p), p);
-	}
-	if (*p != '\0')
-		printf("%s%s\n", indent == NULL ? "" : indent, p);
-}
-
-/*
- * config_doxygen --
- *	Output the configuration information for doxgen.
- */
-static void
-config_doxygen(void)
-{
-	size_t i, nopt;
-	const char *defaultval, *typestr;
-
-	nopt = sizeof(config_opts)/sizeof(config_opts[0]);
-	for (i = 0; i < nopt; i++) {
-		defaultval = config_opts[i].defaultval;
-		typestr = "string";
-		switch (config_opts[i].type) {
-		case BOOL_TYPE:
-			typestr = "boolean";
-			if (strcmp(defaultval, "0") == 0)
-				defaultval = "false";
-			else
-				defaultval = "true";
-			break;
-		case CONFIG_STRING_TYPE:
-		case STRING_TYPE:
-			break;
-		case INT_TYPE:
-			typestr = "int";
-			break;
-		case UINT32_TYPE:
-			typestr = "unsigned int";
-			break;
-		}
-		printf("@par %s (%s, default=%s)\n",
-		    config_opts[i].name, typestr, defaultval);
-		pretty_print(config_opts[i].description, NULL);
-	}
-}
-
-/*
- * config_doxygen --
- *	A standalone program to output the configuration options in a doxygen
- * format.
- */
-int
-main()
-{
-	config_doxygen();
-	return (0);
-}
diff --git a/bench/wtperf/idle_table_cycle.c b/bench/wtperf/idle_table_cycle.c
index 3c079bb560f..13fa55e86f5 100644
--- a/bench/wtperf/idle_table_cycle.c
+++ b/bench/wtperf/idle_table_cycle.c
@@ -29,28 +29,25 @@
 #include "wtperf.h"
 
 static int
-check_timing(CONFIG *cfg,
+check_timing(WTPERF *wtperf,
     const char *name, struct timespec start, struct timespec *stop)
 {
+	CONFIG_OPTS *opts;
 	uint64_t last_interval;
-	int ret;
 
-	if ((ret = __wt_epoch(NULL, stop)) != 0) {
-		lprintf(cfg, ret, 0,
-		    "Get time failed in cycle_idle_tables.");
-		cfg->error = ret;
-		return (ret);
-	}
+	opts = wtperf->opts;
+
+	__wt_epoch(NULL, stop);
 
 	last_interval = (uint64_t)(WT_TIMEDIFF_SEC(*stop, start));
 
-	if (last_interval > cfg->idle_table_cycle) {
-		lprintf(cfg, ret, 0,
+	if (last_interval > opts->idle_table_cycle) {
+		lprintf(wtperf, ETIMEDOUT, 0,
 		    "Cycling idle table failed because %s took %" PRIu64
 		    " seconds which is longer than configured acceptable"
 		    " maximum of %" PRIu32 ".",
-		    name, last_interval, cfg->idle_table_cycle);
-		cfg->error = ETIMEDOUT;
+		    name, last_interval, opts->idle_table_cycle);
+		wtperf->error = true;
 		return (ETIMEDOUT);
 	}
 	return (0);
@@ -64,64 +61,62 @@ static void *
 cycle_idle_tables(void *arg)
 {
 	struct timespec start, stop;
-	CONFIG *cfg;
-	WT_SESSION *session;
+	CONFIG_OPTS *opts;
+	WTPERF *wtperf;
 	WT_CURSOR *cursor;
+	WT_SESSION *session;
 	int cycle_count, ret;
 	char uri[512];
 
-	cfg = (CONFIG *)arg;
+	wtperf = (WTPERF *)arg;
+	opts = wtperf->opts;
 	cycle_count = 0;
 
-	if ((ret = cfg->conn->open_session(
-	    cfg->conn, NULL, cfg->sess_config, &session)) != 0) {
-		lprintf(cfg, ret, 0,
-		    "Error opening a session on %s", cfg->home);
+	if ((ret = wtperf->conn->open_session(
+	    wtperf->conn, NULL, opts->sess_config, &session)) != 0) {
+		lprintf(wtperf, ret, 0,
+		    "Error opening a session on %s", wtperf->home);
 		return (NULL);
 	}
 
-	for (cycle_count = 0; cfg->idle_cycle_run; ++cycle_count) {
-		snprintf(uri, 512, "%s_cycle%07d", cfg->uris[0], cycle_count);
+	for (cycle_count = 0; wtperf->idle_cycle_run; ++cycle_count) {
+		snprintf(uri, sizeof(uri),
+		    "%s_cycle%07d", wtperf->uris[0], cycle_count);
 		/* Don't busy cycle in this loop. */
 		__wt_sleep(1, 0);
 
 		/* Setup a start timer. */
-		if ((ret = __wt_epoch(NULL, &start)) != 0) {
-			lprintf(cfg, ret, 0,
-			     "Get time failed in cycle_idle_tables.");
-			cfg->error = ret;
-			return (NULL);
-		}
+		__wt_epoch(NULL, &start);
 
 		/* Create a table. */
 		if ((ret = session->create(
-		    session, uri, cfg->table_config)) != 0) {
+		    session, uri, opts->table_config)) != 0) {
 			if (ret == EBUSY)
 				continue;
-			lprintf(cfg, ret, 0,
+			lprintf(wtperf, ret, 0,
 			     "Table create failed in cycle_idle_tables.");
-			cfg->error = ret;
+			wtperf->error = true;
 			return (NULL);
 		}
-		if (check_timing(cfg, "create", start, &stop) != 0)
+		if (check_timing(wtperf, "create", start, &stop) != 0)
 			return (NULL);
 		start = stop;
 
 		/* Open and close cursor. */
 		if ((ret = session->open_cursor(
 		    session, uri, NULL, NULL, &cursor)) != 0) {
-			lprintf(cfg, ret, 0,
+			lprintf(wtperf, ret, 0,
 			     "Cursor open failed in cycle_idle_tables.");
-			cfg->error = ret;
+			wtperf->error = true;
 			return (NULL);
 		}
 		if ((ret = cursor->close(cursor)) != 0) {
-			lprintf(cfg, ret, 0,
+			lprintf(wtperf, ret, 0,
 			     "Cursor close failed in cycle_idle_tables.");
-			cfg->error = ret;
+			wtperf->error = true;
 			return (NULL);
 		}
-		if (check_timing(cfg, "cursor", start, &stop) != 0)
+		if (check_timing(wtperf, "cursor", start, &stop) != 0)
 			return (NULL);
 		start = stop;
 
@@ -134,12 +129,12 @@ cycle_idle_tables(void *arg)
 			__wt_sleep(1, 0);
 
 		if (ret != 0 && ret != EBUSY) {
-			lprintf(cfg, ret, 0,
+			lprintf(wtperf, ret, 0,
 			     "Table drop failed in cycle_idle_tables.");
-			cfg->error = ret;
+			wtperf->error = true;
 			return (NULL);
 		}
-		if (check_timing(cfg, "drop", start, &stop) != 0)
+		if (check_timing(wtperf, "drop", start, &stop) != 0)
 			return (NULL);
 	}
 
@@ -154,20 +149,23 @@ cycle_idle_tables(void *arg)
  * initialization isn't necessary.
  */
 int
-start_idle_table_cycle(CONFIG *cfg, pthread_t *idle_table_cycle_thread)
+start_idle_table_cycle(WTPERF *wtperf, pthread_t *idle_table_cycle_thread)
 {
+	CONFIG_OPTS *opts;
 	pthread_t thread_id;
 	int ret;
 
-	if (cfg->idle_table_cycle == 0)
+	opts = wtperf->opts;
+
+	if (opts->idle_table_cycle == 0)
 		return (0);
 
-	cfg->idle_cycle_run = true;
+	wtperf->idle_cycle_run = true;
 	if ((ret = pthread_create(
-	    &thread_id, NULL, cycle_idle_tables, cfg)) != 0) {
-		lprintf(
-		    cfg, ret, 0, "Error creating idle table cycle thread.");
-		cfg->idle_cycle_run = false;
+	    &thread_id, NULL, cycle_idle_tables, wtperf)) != 0) {
+		lprintf(wtperf,
+		    ret, 0, "Error creating idle table cycle thread.");
+		wtperf->idle_cycle_run = false;
 		return (ret);
 	}
 	*idle_table_cycle_thread = thread_id;
@@ -176,17 +174,20 @@ start_idle_table_cycle(CONFIG *cfg, pthread_t *idle_table_cycle_thread)
 }
 
 int
-stop_idle_table_cycle(CONFIG *cfg, pthread_t idle_table_cycle_thread)
+stop_idle_table_cycle(WTPERF *wtperf, pthread_t idle_table_cycle_thread)
 {
+	CONFIG_OPTS *opts;
 	int ret;
 
-	if (cfg->idle_table_cycle == 0 || !cfg->idle_cycle_run)
+	opts = wtperf->opts;
+
+	if (opts->idle_table_cycle == 0 || !wtperf->idle_cycle_run)
 		return (0);
 
-	cfg->idle_cycle_run = false;
+	wtperf->idle_cycle_run = false;
 	if ((ret = pthread_join(idle_table_cycle_thread, NULL)) != 0) {
 		lprintf(
-		    cfg, ret, 0, "Error joining idle table cycle thread.");
+		    wtperf, ret, 0, "Error joining idle table cycle thread.");
 		return (ret);
 	}
 	return (0);
diff --git a/bench/wtperf/misc.c b/bench/wtperf/misc.c
index 2821216f240..24b3323a49a 100644
--- a/bench/wtperf/misc.c
+++ b/bench/wtperf/misc.c
@@ -30,31 +30,34 @@
 
 /* Setup the logging output mechanism. */
 int
-setup_log_file(CONFIG *cfg)
+setup_log_file(WTPERF *wtperf)
 {
+	CONFIG_OPTS *opts;
+	size_t len;
 	int ret;
 	char *fname;
 
+	opts = wtperf->opts;
 	ret = 0;
 
-	if (cfg->verbose < 1)
+	if (opts->verbose < 1)
 		return (0);
 
-	fname = dcalloc(strlen(cfg->monitor_dir) +
-	    strlen(cfg->table_name) + strlen(".stat") + 2, 1);
-
-	sprintf(fname, "%s/%s.stat", cfg->monitor_dir, cfg->table_name);
-	cfg->logf = fopen(fname, "w");
-	if (cfg->logf == NULL) {
+	len = strlen(wtperf->monitor_dir) +
+	    strlen(opts->table_name) + strlen(".stat") + 2;
+	fname = dmalloc(len);
+	snprintf(fname, len,
+	    "%s/%s.stat", wtperf->monitor_dir, opts->table_name);
+	if ((wtperf->logf = fopen(fname, "w")) == NULL) {
 		ret = errno;
 		fprintf(stderr, "%s: %s\n", fname, strerror(ret));
 	}
 	free(fname);
-	if (cfg->logf == NULL)
+	if (wtperf->logf == NULL)
 		return (ret);
 
 	/* Use line buffering for the log file. */
-	__wt_stream_set_line_buffer(cfg->logf);
+	__wt_stream_set_line_buffer(wtperf->logf);
 	return (0);
 }
 
@@ -62,17 +65,20 @@ setup_log_file(CONFIG *cfg)
  * Log printf - output a log message.
  */
 void
-lprintf(const CONFIG *cfg, int err, uint32_t level, const char *fmt, ...)
+lprintf(const WTPERF *wtperf, int err, uint32_t level, const char *fmt, ...)
 {
+	CONFIG_OPTS *opts;
 	va_list ap;
 
-	if (err == 0 && level <= cfg->verbose) {
+	opts = wtperf->opts;
+
+	if (err == 0 && level <= opts->verbose) {
 		va_start(ap, fmt);
-		vfprintf(cfg->logf, fmt, ap);
+		vfprintf(wtperf->logf, fmt, ap);
 		va_end(ap);
-		fprintf(cfg->logf, "\n");
+		fprintf(wtperf->logf, "\n");
 
-		if (level < cfg->verbose) {
+		if (level < opts->verbose) {
 			va_start(ap, fmt);
 			vprintf(fmt, ap);
 			va_end(ap);
@@ -87,11 +93,11 @@ lprintf(const CONFIG *cfg, int err, uint32_t level, const char *fmt, ...)
 	vfprintf(stderr, fmt, ap);
 	va_end(ap);
 	fprintf(stderr, " Error: %s\n", wiredtiger_strerror(err));
-	if (cfg->logf != NULL) {
+	if (wtperf->logf != NULL) {
 		va_start(ap, fmt);
-		vfprintf(cfg->logf, fmt, ap);
+		vfprintf(wtperf->logf, fmt, ap);
 		va_end(ap);
-		fprintf(cfg->logf, " Error: %s\n", wiredtiger_strerror(err));
+		fprintf(wtperf->logf, " Error: %s\n", wiredtiger_strerror(err));
 	}
 
 	/* Never attempt to continue if we got a panic from WiredTiger. */
diff --git a/bench/wtperf/track.c b/bench/wtperf/track.c
index b3f4847d9d0..822bdaa4b4a 100644
--- a/bench/wtperf/track.c
+++ b/bench/wtperf/track.c
@@ -32,16 +32,18 @@
  * Return total insert operations for the populate phase.
  */
 uint64_t
-sum_pop_ops(CONFIG *cfg)
+sum_pop_ops(WTPERF *wtperf)
 {
-	CONFIG_THREAD *thread;
+	CONFIG_OPTS *opts;
+	WTPERF_THREAD *thread;
 	uint64_t total;
 	u_int i;
 
+	opts = wtperf->opts;
 	total = 0;
 
-	for (i = 0, thread = cfg->popthreads;
-	    thread != NULL && i < cfg->populate_threads; ++i, ++thread)
+	for (i = 0, thread = wtperf->popthreads;
+	    thread != NULL && i < opts->populate_threads; ++i, ++thread)
 		total += thread->insert.ops;
 	return (total);
 }
@@ -50,16 +52,18 @@ sum_pop_ops(CONFIG *cfg)
  * Return total checkpoint operations.
  */
 uint64_t
-sum_ckpt_ops(CONFIG *cfg)
+sum_ckpt_ops(WTPERF *wtperf)
 {
-	CONFIG_THREAD *thread;
+	CONFIG_OPTS *opts;
+	WTPERF_THREAD *thread;
 	uint64_t total;
 	u_int i;
 
+	opts = wtperf->opts;
 	total = 0;
 
-	for (i = 0, thread = cfg->ckptthreads;
-	    thread != NULL && i < cfg->checkpoint_threads; ++i, ++thread)
+	for (i = 0, thread = wtperf->ckptthreads;
+	    thread != NULL && i < opts->checkpoint_threads; ++i, ++thread)
 		total += thread->ckpt.ops;
 	return (total);
 }
@@ -68,19 +72,22 @@ sum_ckpt_ops(CONFIG *cfg)
  * Return total operations count for the worker threads.
  */
 static uint64_t
-sum_ops(CONFIG *cfg, size_t field_offset)
+sum_ops(WTPERF *wtperf, size_t field_offset)
 {
-	CONFIG_THREAD *thread;
+	CONFIG_OPTS *opts;
+	WTPERF_THREAD *thread;
 	uint64_t total;
 	int64_t i, th_cnt;
 
+	opts = wtperf->opts;
 	total = 0;
-	if (cfg->popthreads == NULL) {
-		thread = cfg->workers;
-		th_cnt = cfg->workers_cnt;
+
+	if (wtperf->popthreads == NULL) {
+		thread = wtperf->workers;
+		th_cnt = wtperf->workers_cnt;
 	} else {
-		thread = cfg->popthreads;
-		th_cnt = cfg->populate_threads;
+		thread = wtperf->popthreads;
+		th_cnt = opts->populate_threads;
 	}
 	for (i = 0; thread != NULL && i < th_cnt; ++i, ++thread)
 		total += ((TRACK *)((uint8_t *)thread + field_offset))->ops;
@@ -88,24 +95,24 @@ sum_ops(CONFIG *cfg, size_t field_offset)
 	return (total);
 }
 uint64_t
-sum_insert_ops(CONFIG *cfg)
+sum_insert_ops(WTPERF *wtperf)
 {
-	return (sum_ops(cfg, offsetof(CONFIG_THREAD, insert)));
+	return (sum_ops(wtperf, offsetof(WTPERF_THREAD, insert)));
 }
 uint64_t
-sum_read_ops(CONFIG *cfg)
+sum_read_ops(WTPERF *wtperf)
 {
-	return (sum_ops(cfg, offsetof(CONFIG_THREAD, read)));
+	return (sum_ops(wtperf, offsetof(WTPERF_THREAD, read)));
 }
 uint64_t
-sum_truncate_ops(CONFIG *cfg)
+sum_truncate_ops(WTPERF *wtperf)
 {
-	return (sum_ops(cfg, offsetof(CONFIG_THREAD, truncate)));
+	return (sum_ops(wtperf, offsetof(WTPERF_THREAD, truncate)));
 }
 uint64_t
-sum_update_ops(CONFIG *cfg)
+sum_update_ops(WTPERF *wtperf)
 {
-	return (sum_ops(cfg, offsetof(CONFIG_THREAD, update)));
+	return (sum_ops(wtperf, offsetof(WTPERF_THREAD, update)));
 }
 
 /*
@@ -114,25 +121,27 @@ sum_update_ops(CONFIG *cfg)
  * particular operation.
  */
 static void
-latency_op(CONFIG *cfg,
+latency_op(WTPERF *wtperf,
     size_t field_offset, uint32_t *avgp, uint32_t *minp, uint32_t *maxp)
 {
-	CONFIG_THREAD *thread;
+	CONFIG_OPTS *opts;
 	TRACK *track;
+	WTPERF_THREAD *thread;
 	uint64_t ops, latency, tmp;
 	int64_t i, th_cnt;
 	uint32_t max, min;
 
+	opts = wtperf->opts;
 	ops = latency = 0;
 	max = 0;
 	min = UINT32_MAX;
 
-	if (cfg->popthreads == NULL) {
-		thread = cfg->workers;
-		th_cnt = cfg->workers_cnt;
+	if (wtperf->popthreads == NULL) {
+		thread = wtperf->workers;
+		th_cnt = wtperf->workers_cnt;
 	} else {
-		thread = cfg->popthreads;
-		th_cnt = cfg->populate_threads;
+		thread = wtperf->popthreads;
+		th_cnt = opts->populate_threads;
 	}
 	for (i = 0; thread != NULL && i < th_cnt; ++i, ++thread) {
 		track = (TRACK *)((uint8_t *)thread + field_offset);
@@ -160,11 +169,11 @@ latency_op(CONFIG *cfg,
 	}
 }
 void
-latency_read(CONFIG *cfg, uint32_t *avgp, uint32_t *minp, uint32_t *maxp)
+latency_read(WTPERF *wtperf, uint32_t *avgp, uint32_t *minp, uint32_t *maxp)
 {
 	static uint32_t last_avg = 0, last_max = 0, last_min = 0;
 
-	latency_op(cfg, offsetof(CONFIG_THREAD, read), avgp, minp, maxp);
+	latency_op(wtperf, offsetof(WTPERF_THREAD, read), avgp, minp, maxp);
 
 	/*
 	 * If nothing happened, graph the average, minimum and maximum as they
@@ -181,11 +190,11 @@ latency_read(CONFIG *cfg, uint32_t *avgp, uint32_t *minp, uint32_t *maxp)
 	}
 }
 void
-latency_insert(CONFIG *cfg, uint32_t *avgp, uint32_t *minp, uint32_t *maxp)
+latency_insert(WTPERF *wtperf, uint32_t *avgp, uint32_t *minp, uint32_t *maxp)
 {
 	static uint32_t last_avg = 0, last_max = 0, last_min = 0;
 
-	latency_op(cfg, offsetof(CONFIG_THREAD, insert), avgp, minp, maxp);
+	latency_op(wtperf, offsetof(WTPERF_THREAD, insert), avgp, minp, maxp);
 
 	/*
 	 * If nothing happened, graph the average, minimum and maximum as they
@@ -202,11 +211,11 @@ latency_insert(CONFIG *cfg, uint32_t *avgp, uint32_t *minp, uint32_t *maxp)
 	}
 }
 void
-latency_update(CONFIG *cfg, uint32_t *avgp, uint32_t *minp, uint32_t *maxp)
+latency_update(WTPERF *wtperf, uint32_t *avgp, uint32_t *minp, uint32_t *maxp)
 {
 	static uint32_t last_avg = 0, last_max = 0, last_min = 0;
 
-	latency_op(cfg, offsetof(CONFIG_THREAD, update), avgp, minp, maxp);
+	latency_op(wtperf, offsetof(WTPERF_THREAD, update), avgp, minp, maxp);
 
 	/*
 	 * If nothing happened, graph the average, minimum and maximum as they
@@ -228,17 +237,17 @@ latency_update(CONFIG *cfg, uint32_t *avgp, uint32_t *minp, uint32_t *maxp)
  *	Sum latency for a set of threads.
  */
 static void
-sum_latency(CONFIG *cfg, size_t field_offset, TRACK *total)
+sum_latency(WTPERF *wtperf, size_t field_offset, TRACK *total)
 {
-	CONFIG_THREAD *thread;
+	WTPERF_THREAD *thread;
 	TRACK *trk;
 	int64_t i;
 	u_int j;
 
 	memset(total, 0, sizeof(*total));
 
-	for (i = 0, thread = cfg->workers;
-	    thread != NULL && i < cfg->workers_cnt; ++i, ++thread) {
+	for (i = 0, thread = wtperf->workers;
+	    thread != NULL && i < wtperf->workers_cnt; ++i, ++thread) {
 		trk = (TRACK *)((uint8_t *)thread + field_offset);
 
 		for (j = 0; j < ELEMENTS(trk->us); ++j) {
@@ -256,32 +265,33 @@ sum_latency(CONFIG *cfg, size_t field_offset, TRACK *total)
 	}
 }
 static void
-sum_insert_latency(CONFIG *cfg, TRACK *total)
+sum_insert_latency(WTPERF *wtperf, TRACK *total)
 {
-	sum_latency(cfg, offsetof(CONFIG_THREAD, insert), total);
+	sum_latency(wtperf, offsetof(WTPERF_THREAD, insert), total);
 }
 static void
-sum_read_latency(CONFIG *cfg, TRACK *total)
+sum_read_latency(WTPERF *wtperf, TRACK *total)
 {
-	sum_latency(cfg, offsetof(CONFIG_THREAD, read), total);
+	sum_latency(wtperf, offsetof(WTPERF_THREAD, read), total);
 }
 static void
-sum_update_latency(CONFIG *cfg, TRACK *total)
+sum_update_latency(WTPERF *wtperf, TRACK *total)
 {
-	sum_latency(cfg, offsetof(CONFIG_THREAD, update), total);
+	sum_latency(wtperf, offsetof(WTPERF_THREAD, update), total);
 }
 
 static void
-latency_print_single(CONFIG *cfg, TRACK *total, const char *name)
+latency_print_single(WTPERF *wtperf, TRACK *total, const char *name)
 {
 	FILE *fp;
 	u_int i;
 	uint64_t cumops;
 	char path[1024];
 
-	snprintf(path, sizeof(path), "%s/latency.%s", cfg->monitor_dir, name);
+	snprintf(path, sizeof(path),
+	    "%s/latency.%s", wtperf->monitor_dir, name);
 	if ((fp = fopen(path, "w")) == NULL) {
-		lprintf(cfg, errno, 0, "%s", path);
+		lprintf(wtperf, errno, 0, "%s", path);
 		return;
 	}
 
@@ -317,14 +327,14 @@ latency_print_single(CONFIG *cfg, TRACK *total, const char *name)
 }
 
 void
-latency_print(CONFIG *cfg)
+latency_print(WTPERF *wtperf)
 {
 	TRACK total;
 
-	sum_insert_latency(cfg, &total);
-	latency_print_single(cfg, &total, "insert");
-	sum_read_latency(cfg, &total);
-	latency_print_single(cfg, &total, "read");
-	sum_update_latency(cfg, &total);
-	latency_print_single(cfg, &total, "update");
+	sum_insert_latency(wtperf, &total);
+	latency_print_single(wtperf, &total, "insert");
+	sum_read_latency(wtperf, &total);
+	latency_print_single(wtperf, &total, "read");
+	sum_update_latency(wtperf, &total);
+	latency_print_single(wtperf, &total, "update");
 }
diff --git a/bench/wtperf/wtperf.c b/bench/wtperf/wtperf.c
index bf6b156bb69..a7618b19707 100644
--- a/bench/wtperf/wtperf.c
+++ b/bench/wtperf/wtperf.c
@@ -31,78 +31,38 @@
 /* Default values. */
 #define	DEFAULT_HOME		"WT_TEST"
 #define	DEFAULT_MONITOR_DIR	"WT_TEST"
-static const CONFIG default_cfg = {
-	NULL,				/* home */
-	NULL,				/* monitor dir */
-	NULL,				/* partial logging */
-	NULL,				/* reopen config */
-	NULL,				/* base_uri */
-	NULL,				/* log_table_uri */
-	NULL,				/* uris */
-	NULL,				/* conn */
-	NULL,				/* logf */
-	NULL,				/* async */
-	NULL, NULL,			/* compressor ext, blk */
-	NULL, NULL,			/* populate, checkpoint threads */
-
-	NULL,				/* worker threads */
-	0,				/* worker thread count */
-	NULL,				/* workloads */
-	0,				/* workload count */
-	0,				/* use_asyncops */
-	0,				/* checkpoint operations */
-	0,				/* insert operations */
-	0,				/* read operations */
-	0,				/* truncate operations */
-	0,				/* update operations */
-	0,				/* insert key */
-	0,				/* log like table key */
-	0,				/* checkpoint in progress */
-	0,				/* thread error */
-	0,				/* notify threads to stop */
-	0,				/* in warmup phase */
-	false,				/* Signal for idle cycle thread */
-	0,				/* total seconds running */
-	0,				/* flags */
-	{NULL, NULL},			/* the truncate queue */
-	{NULL, NULL},                   /* the config queue */
-
-#define	OPT_DEFINE_DEFAULT
-#include "wtperf_opt.i"
-#undef OPT_DEFINE_DEFAULT
-};
 
 static const char * const debug_cconfig = "";
 static const char * const debug_tconfig = "";
 
 static void	*checkpoint_worker(void *);
-static int	 drop_all_tables(CONFIG *);
-static int	 execute_populate(CONFIG *);
-static int	 execute_workload(CONFIG *);
-static int	 find_table_count(CONFIG *);
+static int	 drop_all_tables(WTPERF *);
+static int	 execute_populate(WTPERF *);
+static int	 execute_workload(WTPERF *);
+static int	 find_table_count(WTPERF *);
 static void	*monitor(void *);
 static void	*populate_thread(void *);
-static void	 randomize_value(CONFIG_THREAD *, char *);
+static void	 randomize_value(WTPERF_THREAD *, char *);
 static void	 recreate_dir(const char *);
-static int	 start_all_runs(CONFIG *);
-static int	 start_run(CONFIG *);
-static int	 start_threads(CONFIG *,
-		    WORKLOAD *, CONFIG_THREAD *, u_int, void *(*)(void *));
-static int	 stop_threads(CONFIG *, u_int, CONFIG_THREAD *);
+static int	 start_all_runs(WTPERF *);
+static int	 start_run(WTPERF *);
+static int	 start_threads(WTPERF *,
+		    WORKLOAD *, WTPERF_THREAD *, u_int, void *(*)(void *));
+static int	 stop_threads(WTPERF *, u_int, WTPERF_THREAD *);
 static void	*thread_run_wtperf(void *);
-static void	 update_value_delta(CONFIG_THREAD *);
+static void	 update_value_delta(WTPERF_THREAD *);
 static void	*worker(void *);
 
-static uint64_t	 wtperf_rand(CONFIG_THREAD *);
-static uint64_t	 wtperf_value_range(CONFIG *);
+static uint64_t	 wtperf_rand(WTPERF_THREAD *);
+static uint64_t	 wtperf_value_range(WTPERF *);
 
-#define	INDEX_COL_NAMES	",columns=(key,val)"
+#define	INDEX_COL_NAMES	"columns=(key,val)"
 
 /* Retrieve an ID for the next insert operation. */
 static inline uint64_t
-get_next_incr(CONFIG *cfg)
+get_next_incr(WTPERF *wtperf)
 {
-	return (__wt_atomic_add64(&cfg->insert_key, 1));
+	return (__wt_atomic_add64(&wtperf->insert_key, 1));
 }
 
 /*
@@ -110,11 +70,14 @@ get_next_incr(CONFIG *cfg)
  * other element in the value buffer.
  */
 static void
-randomize_value(CONFIG_THREAD *thread, char *value_buf)
+randomize_value(WTPERF_THREAD *thread, char *value_buf)
 {
+	CONFIG_OPTS *opts;
 	uint8_t *vb;
 	uint32_t i, max_range, rand_val;
 
+	opts = thread->wtperf->opts;
+
 	/*
 	 * Limit how much of the buffer we validate for length, this means
 	 * that only threads that do growing updates will ever make changes to
@@ -123,11 +86,11 @@ randomize_value(CONFIG_THREAD *thread, char *value_buf)
 	 * in this performance sensitive function.
 	 */
 	if (thread->workload == NULL || thread->workload->update_delta == 0)
-		max_range = thread->cfg->value_sz;
+		max_range = opts->value_sz;
 	else if (thread->workload->update_delta > 0)
-		max_range = thread->cfg->value_sz_max;
+		max_range = opts->value_sz_max;
 	else
-		max_range = thread->cfg->value_sz_min;
+		max_range = opts->value_sz_min;
 
 	/*
 	 * Generate a single random value and re-use it. We generally only
@@ -157,17 +120,17 @@ randomize_value(CONFIG_THREAD *thread, char *value_buf)
  * Partition data by key ranges.
  */
 static uint32_t
-map_key_to_table(CONFIG *cfg, uint64_t k)
+map_key_to_table(CONFIG_OPTS *opts, uint64_t k)
 {
-	if (cfg->range_partition) {
+	if (opts->range_partition) {
 		/* Take care to return a result in [0..table_count-1]. */
-		if (k > cfg->icount + cfg->random_range)
+		if (k > opts->icount + opts->random_range)
 			return (0);
 		return ((uint32_t)((k - 1) /
-		    ((cfg->icount + cfg->random_range + cfg->table_count - 1) /
-		    cfg->table_count)));
+		    ((opts->icount + opts->random_range +
+		    opts->table_count - 1) / opts->table_count)));
 	} else
-		return ((uint32_t)(k % cfg->table_count));
+		return ((uint32_t)(k % opts->table_count));
 }
 
 /*
@@ -176,26 +139,28 @@ map_key_to_table(CONFIG *cfg, uint64_t k)
  * scratch buffer.
  */
 static inline void
-update_value_delta(CONFIG_THREAD *thread)
+update_value_delta(WTPERF_THREAD *thread)
 {
-	CONFIG *cfg;
+	CONFIG_OPTS *opts;
+	WTPERF *wtperf;
 	char * value;
 	int64_t delta, len, new_len;
 
-	cfg = thread->cfg;
+	wtperf = thread->wtperf;
+	opts = wtperf->opts;
 	value = thread->value_buf;
 	delta = thread->workload->update_delta;
 	len = (int64_t)strlen(value);
 
 	if (delta == INT64_MAX)
 		delta = __wt_random(&thread->rnd) %
-		    (cfg->value_sz_max - cfg->value_sz);
+		    (opts->value_sz_max - opts->value_sz);
 
 	/* Ensure we aren't changing across boundaries */
-	if (delta > 0 && len + delta > cfg->value_sz_max)
-		delta = cfg->value_sz_max - len;
-	else if (delta < 0 && len + delta < cfg->value_sz_min)
-		delta = cfg->value_sz_min - len;
+	if (delta > 0 && len + delta > opts->value_sz_max)
+		delta = opts->value_sz_max - len;
+	else if (delta < 0 && len + delta < opts->value_sz_min)
+		delta = opts->value_sz_min - len;
 
 	/* Bail if there isn't anything to do */
 	if (delta == 0)
@@ -206,7 +171,7 @@ update_value_delta(CONFIG_THREAD *thread)
 	else {
 		/* Extend the value by the configured amount. */
 		for (new_len = len;
-		    new_len < cfg->value_sz_max && new_len - len < delta;
+		    new_len < opts->value_sz_max && new_len - len < delta;
 		    new_len++)
 			value[new_len] = 'a';
 	}
@@ -215,24 +180,24 @@ update_value_delta(CONFIG_THREAD *thread)
 static int
 cb_asyncop(WT_ASYNC_CALLBACK *cb, WT_ASYNC_OP *op, int ret, uint32_t flags)
 {
-	CONFIG *cfg;
-	CONFIG_THREAD *thread;
 	TRACK *trk;
+	WTPERF *wtperf;
+	WTPERF_THREAD *thread;
 	WT_ASYNC_OPTYPE type;
-	char *value;
 	uint32_t *tables;
 	int t_ret;
+	char *value;
 
 	(void)cb;
 	(void)flags;
 
-	cfg = NULL;			/* -Wconditional-uninitialized */
+	wtperf = NULL;			/* -Wconditional-uninitialized */
 	thread = NULL;			/* -Wconditional-uninitialized */
 
 	type = op->get_type(op);
 	if (type != WT_AOP_COMPACT) {
-		thread = (CONFIG_THREAD *)op->app_private;
-		cfg = thread->cfg;
+		thread = (WTPERF_THREAD *)op->app_private;
+		wtperf = thread->wtperf;
 	}
 
 	trk = NULL;
@@ -249,7 +214,7 @@ cb_asyncop(WT_ASYNC_CALLBACK *cb, WT_ASYNC_OP *op, int ret, uint32_t flags)
 		if (ret == 0 &&
 		    (t_ret = op->get_value(op, &value)) != 0) {
 			ret = t_ret;
-			lprintf(cfg, ret, 0, "get_value in read.");
+			lprintf(wtperf, ret, 0, "get_value in read.");
 			goto err;
 		}
 		break;
@@ -259,7 +224,8 @@ cb_asyncop(WT_ASYNC_CALLBACK *cb, WT_ASYNC_OP *op, int ret, uint32_t flags)
 	case WT_AOP_NONE:
 	case WT_AOP_REMOVE:
 		/* We never expect this type. */
-		lprintf(cfg, ret, 0, "No type in op %" PRIu64, op->get_id(op));
+		lprintf(wtperf,
+		    ret, 0, "No type in op %" PRIu64, op->get_id(op));
 		goto err;
 	}
 
@@ -273,15 +239,14 @@ cb_asyncop(WT_ASYNC_CALLBACK *cb, WT_ASYNC_OP *op, int ret, uint32_t flags)
 	if (type == WT_AOP_COMPACT)
 		return (0);
 	if (ret == 0 || (ret == WT_NOTFOUND && type != WT_AOP_INSERT)) {
-		if (!cfg->in_warmup)
+		if (!wtperf->in_warmup)
 			(void)__wt_atomic_add64(&trk->ops, 1);
 		return (0);
 	}
 err:
 	/* Panic if error */
-	lprintf(cfg, ret, 0, "Error in op %" PRIu64,
-	    op->get_id(op));
-	cfg->error = cfg->stop = 1;
+	lprintf(wtperf, ret, 0, "Error in op %" PRIu64, op->get_id(op));
+	wtperf->error = wtperf->stop = true;
 	return (1);
 }
 
@@ -353,8 +318,9 @@ op_name(uint8_t *op)
 static void *
 worker_async(void *arg)
 {
-	CONFIG *cfg;
-	CONFIG_THREAD *thread;
+	CONFIG_OPTS *opts;
+	WTPERF *wtperf;
+	WTPERF_THREAD *thread;
 	WT_ASYNC_OP *asyncop;
 	WT_CONNECTION *conn;
 	uint64_t next_val;
@@ -362,9 +328,10 @@ worker_async(void *arg)
 	int ret;
 	char *key_buf, *value_buf;
 
-	thread = (CONFIG_THREAD *)arg;
-	cfg = thread->cfg;
-	conn = cfg->conn;
+	thread = (WTPERF_THREAD *)arg;
+	wtperf = thread->wtperf;
+	opts = wtperf->opts;
+	conn = wtperf->conn;
 
 	key_buf = thread->key_buf;
 	value_buf = thread->value_buf;
@@ -372,7 +339,7 @@ worker_async(void *arg)
 	op = thread->workload->ops;
 	op_end = op + sizeof(thread->workload->ops);
 
-	while (!cfg->stop) {
+	while (!wtperf->stop) {
 		/*
 		 * Generate the next key and setup operation specific
 		 * statistics tracking objects.
@@ -380,10 +347,10 @@ worker_async(void *arg)
 		switch (*op) {
 		case WORKER_INSERT:
 		case WORKER_INSERT_RMW:
-			if (cfg->random_range)
+			if (opts->random_range)
 				next_val = wtperf_rand(thread);
 			else
-				next_val = cfg->icount + get_next_incr(cfg);
+				next_val = opts->icount + get_next_incr(wtperf);
 			break;
 		case WORKER_READ:
 		case WORKER_UPDATE:
@@ -394,22 +361,22 @@ worker_async(void *arg)
 			 * we rely on at least one insert to get a valid item
 			 * id.
 			 */
-			if (wtperf_value_range(cfg) < next_val)
+			if (wtperf_value_range(wtperf) < next_val)
 				continue;
 			break;
 		default:
 			goto err;		/* can't happen */
 		}
 
-		generate_key(cfg, key_buf, next_val);
+		generate_key(opts, key_buf, next_val);
 
 		/*
 		 * Spread the data out around the multiple databases.
 		 * Sleep to allow workers a chance to run and process async ops.
 		 * Then retry to get an async op.
 		 */
-		while ((ret = conn->async_new_op(
-		    conn, cfg->uris[map_key_to_table(cfg, next_val)],
+		while ((ret = conn->async_new_op(conn,
+		    wtperf->uris[map_key_to_table(wtperf->opts, next_val)],
 		    NULL, &cb, &asyncop)) == EBUSY)
 			(void)usleep(10000);
 		if (ret != 0)
@@ -424,23 +391,23 @@ worker_async(void *arg)
 				break;
 			goto op_err;
 		case WORKER_INSERT:
-			if (cfg->random_value)
+			if (opts->random_value)
 				randomize_value(thread, value_buf);
 			asyncop->set_value(asyncop, value_buf);
 			if ((ret = asyncop->insert(asyncop)) == 0)
 				break;
 			goto op_err;
 		case WORKER_UPDATE:
-			if (cfg->random_value)
+			if (opts->random_value)
 				randomize_value(thread, value_buf);
 			asyncop->set_value(asyncop, value_buf);
 			if ((ret = asyncop->update(asyncop)) == 0)
 				break;
 			goto op_err;
 		default:
-op_err:			lprintf(cfg, ret, 0,
+op_err:			lprintf(wtperf, ret, 0,
 			    "%s failed for: %s, range: %"PRIu64,
-			    op_name(op), key_buf, wtperf_value_range(cfg));
+			    op_name(op), key_buf, wtperf_value_range(wtperf));
 			goto err;		/* can't happen */
 		}
 
@@ -454,7 +421,7 @@ op_err:			lprintf(cfg, ret, 0,
 
 	/* Notify our caller we failed and shut the system down. */
 	if (0) {
-err:		cfg->error = cfg->stop = 1;
+err:		wtperf->error = wtperf->stop = true;
 	}
 	return (NULL);
 }
@@ -465,17 +432,19 @@ err:		cfg->error = cfg->stop = 1;
  *	search do them. Ensuring the keys we see are always in order.
  */
 static int
-do_range_reads(CONFIG *cfg, WT_CURSOR *cursor)
+do_range_reads(WTPERF *wtperf, WT_CURSOR *cursor)
 {
+	CONFIG_OPTS *opts;
 	size_t range;
 	uint64_t next_val, prev_val;
 	char *range_key_buf;
 	char buf[512];
 	int ret;
 
+	opts = wtperf->opts;
 	ret = 0;
 
-	if (cfg->read_range == 0)
+	if (opts->read_range == 0)
 		return (0);
 
 	memset(&buf[0], 0, 512 * sizeof(char));
@@ -485,7 +454,7 @@ do_range_reads(CONFIG *cfg, WT_CURSOR *cursor)
 	testutil_check(cursor->get_key(cursor, &range_key_buf));
 	extract_key(range_key_buf, &next_val);
 
-	for (range = 0; range < cfg->read_range; ++range) {
+	for (range = 0; range < opts->read_range; ++range) {
 		prev_val = next_val;
 		ret = cursor->next(cursor);
 		/* We are done if we reach the end. */
@@ -496,7 +465,7 @@ do_range_reads(CONFIG *cfg, WT_CURSOR *cursor)
 		testutil_check(cursor->get_key(cursor, &range_key_buf));
 		extract_key(range_key_buf, &next_val);
 		if (next_val < prev_val) {
-			lprintf(cfg, EINVAL, 0,
+			lprintf(wtperf, EINVAL, 0,
 			    "Out of order keys %" PRIu64
 			    " came before %" PRIu64,
 			    prev_val, next_val);
@@ -510,9 +479,10 @@ static void *
 worker(void *arg)
 {
 	struct timespec start, stop;
-	CONFIG *cfg;
-	CONFIG_THREAD *thread;
+	CONFIG_OPTS *opts;
 	TRACK *trk;
+	WTPERF *wtperf;
+	WTPERF_THREAD *thread;
 	WT_CONNECTION *conn;
 	WT_CURSOR **cursors, *cursor, *log_table_cursor, *tmp_cursor;
 	WT_SESSION *session;
@@ -524,9 +494,10 @@ worker(void *arg)
 	char *value_buf, *key_buf, *value;
 	char buf[512];
 
-	thread = (CONFIG_THREAD *)arg;
-	cfg = thread->cfg;
-	conn = cfg->conn;
+	thread = (WTPERF_THREAD *)arg;
+	wtperf = thread->wtperf;
+	opts = wtperf->opts;
+	conn = wtperf->conn;
 	cursors = NULL;
 	log_table_cursor = NULL;	/* -Wconditional-initialized */
 	ops = 0;
@@ -535,42 +506,40 @@ worker(void *arg)
 	trk = NULL;
 
 	if ((ret = conn->open_session(
-	    conn, NULL, cfg->sess_config, &session)) != 0) {
-		lprintf(cfg, ret, 0, "worker: WT_CONNECTION.open_session");
+	    conn, NULL, opts->sess_config, &session)) != 0) {
+		lprintf(wtperf, ret, 0, "worker: WT_CONNECTION.open_session");
 		goto err;
 	}
-	cursors = dcalloc(cfg->table_count, sizeof(WT_CURSOR *));
-	for (i = 0; i < cfg->table_count_idle; i++) {
-		snprintf(buf, 512, "%s_idle%05d", cfg->uris[0], (int)i);
+	cursors = dcalloc(opts->table_count, sizeof(WT_CURSOR *));
+	for (i = 0; i < opts->table_count_idle; i++) {
+		snprintf(buf, 512, "%s_idle%05d", wtperf->uris[0], (int)i);
 		if ((ret = session->open_cursor(
 		    session, buf, NULL, NULL, &tmp_cursor)) != 0) {
-			lprintf(cfg, ret, 0,
+			lprintf(wtperf, ret, 0,
 			    "Error opening idle table %s", buf);
 			goto err;
 		}
 		if ((ret = tmp_cursor->close(tmp_cursor)) != 0) {
-			lprintf(cfg, ret, 0,
+			lprintf(wtperf, ret, 0,
 			    "Error closing idle table %s", buf);
 			goto err;
 		}
 	}
-	for (i = 0; i < cfg->table_count; i++) {
+	for (i = 0; i < opts->table_count; i++) {
 		if ((ret = session->open_cursor(session,
-		    cfg->uris[i], NULL, NULL, &cursors[i])) != 0) {
-			lprintf(cfg, ret, 0,
+		    wtperf->uris[i], NULL, NULL, &cursors[i])) != 0) {
+			lprintf(wtperf, ret, 0,
 			    "worker: WT_SESSION.open_cursor: %s",
-			    cfg->uris[i]);
+			    wtperf->uris[i]);
 			goto err;
 		}
 	}
-	if (cfg->log_like_table) {
-		if ((ret = session->open_cursor(session,
-		    cfg->log_table_uri, NULL, NULL, &log_table_cursor)) != 0) {
-			lprintf(cfg, ret, 0,
-			    "worker: WT_SESSION.open_cursor: %s",
-			    cfg->log_table_uri);
-			goto err;
-		}
+	if (opts->log_like_table && (ret = session->open_cursor(session,
+	    wtperf->log_table_uri, NULL, NULL, &log_table_cursor)) != 0) {
+		lprintf(wtperf, ret, 0,
+		    "worker: WT_SESSION.open_cursor: %s",
+		    wtperf->log_table_uri);
+		goto err;
 	}
 
 	/* Setup the timer for throttling. */
@@ -579,7 +548,7 @@ worker(void *arg)
 
 	/* Setup for truncate */
 	if (thread->workload->truncate != 0)
-		if ((ret = setup_truncate(cfg, thread, session)) != 0)
+		if ((ret = setup_truncate(wtperf, thread, session)) != 0)
 			goto err;
 
 	key_buf = thread->key_buf;
@@ -588,13 +557,13 @@ worker(void *arg)
 	op = thread->workload->ops;
 	op_end = op + sizeof(thread->workload->ops);
 
-	if ((ops_per_txn != 0 || cfg->log_like_table) &&
+	if ((ops_per_txn != 0 || opts->log_like_table) &&
 		(ret = session->begin_transaction(session, NULL)) != 0) {
-		lprintf(cfg, ret, 0, "First transaction begin failed");
+		lprintf(wtperf, ret, 0, "First transaction begin failed");
 		goto err;
 	}
 
-	while (!cfg->stop) {
+	while (!wtperf->stop) {
 		/*
 		 * Generate the next key and setup operation specific
 		 * statistics tracking objects.
@@ -603,10 +572,10 @@ worker(void *arg)
 		case WORKER_INSERT:
 		case WORKER_INSERT_RMW:
 			trk = &thread->insert;
-			if (cfg->random_range)
+			if (opts->random_range)
 				next_val = wtperf_rand(thread);
 			else
-				next_val = cfg->icount + get_next_incr(cfg);
+				next_val = opts->icount + get_next_incr(wtperf);
 			break;
 		case WORKER_READ:
 			trk = &thread->read;
@@ -621,7 +590,7 @@ worker(void *arg)
 			 * we rely on at least one insert to get a valid item
 			 * id.
 			 */
-			if (wtperf_value_range(cfg) < next_val)
+			if (wtperf_value_range(wtperf) < next_val)
 				continue;
 			break;
 		case WORKER_TRUNCATE:
@@ -632,24 +601,22 @@ worker(void *arg)
 			goto err;		/* can't happen */
 		}
 
-		generate_key(cfg, key_buf, next_val);
+		generate_key(opts, key_buf, next_val);
 
 		/*
 		 * Spread the data out around the multiple databases.
 		 */
-		cursor = cursors[map_key_to_table(cfg, next_val)];
+		cursor = cursors[map_key_to_table(wtperf->opts, next_val)];
 
 		/*
 		 * Skip the first time we do an operation, when trk->ops
 		 * is 0, to avoid first time latency spikes.
 		 */
 		measure_latency =
-		    cfg->sample_interval != 0 && trk != NULL &&
-		    trk->ops != 0 && (trk->ops % cfg->sample_rate == 0);
-		if (measure_latency && (ret = __wt_epoch(NULL, &start)) != 0) {
-			lprintf(cfg, ret, 0, "Get time call failed");
-			goto err;
-		}
+		    opts->sample_interval != 0 && trk != NULL &&
+		    trk->ops != 0 && (trk->ops % opts->sample_rate == 0);
+		if (measure_latency)
+			__wt_epoch(NULL, &start);
 
 		cursor->set_key(cursor, key_buf);
 
@@ -666,7 +633,7 @@ worker(void *arg)
 			if (ret == 0) {
 				if ((ret = cursor->get_value(
 				    cursor, &value)) != 0) {
-					lprintf(cfg, ret, 0,
+					lprintf(wtperf, ret, 0,
 					    "get_value in read.");
 					goto err;
 				}
@@ -675,7 +642,7 @@ worker(void *arg)
 				 * for several operations, confirming that the
 				 * next key is in the correct order.
 				 */
-				ret = do_range_reads(cfg, cursor);
+				ret = do_range_reads(wtperf, cursor);
 			}
 
 			if (ret == 0 || ret == WT_NOTFOUND)
@@ -690,15 +657,15 @@ worker(void *arg)
 
 			/* FALLTHROUGH */
 		case WORKER_INSERT:
-			if (cfg->random_value)
+			if (opts->random_value)
 				randomize_value(thread, value_buf);
 			cursor->set_value(cursor, value_buf);
 			if ((ret = cursor->insert(cursor)) == 0)
 				break;
 			goto op_err;
 		case WORKER_TRUNCATE:
-			if ((ret = run_truncate(
-			    cfg, thread, cursor, session, &truncated)) == 0) {
+			if ((ret = run_truncate(wtperf,
+			    thread, cursor, session, &truncated)) == 0) {
 				if (truncated)
 					trk = &thread->truncate;
 				else
@@ -712,7 +679,7 @@ worker(void *arg)
 			if ((ret = cursor->search(cursor)) == 0) {
 				if ((ret = cursor->get_value(
 				    cursor, &value)) != 0) {
-					lprintf(cfg, ret, 0,
+					lprintf(wtperf, ret, 0,
 					    "get_value in update.");
 					goto err;
 				}
@@ -721,14 +688,14 @@ worker(void *arg)
 				 * safe, and be sure to NUL-terminate.
 				 */
 				strncpy(value_buf,
-				    value, cfg->value_sz_max - 1);
+				    value, opts->value_sz_max - 1);
 				if (thread->workload->update_delta != 0)
 					update_value_delta(thread);
 				if (value_buf[0] == 'a')
 					value_buf[0] = 'b';
 				else
 					value_buf[0] = 'a';
-				if (cfg->random_value)
+				if (opts->random_value)
 					randomize_value(thread, value_buf);
 				cursor->set_value(cursor, value_buf);
 				if ((ret = cursor->update(cursor)) == 0)
@@ -756,62 +723,59 @@ op_err:			if (ret == WT_ROLLBACK && ops_per_txn != 0) {
 				 * order in cases of ordered inserts, as we
 				 * aren't retrying here.
 				 */
-				lprintf(cfg, ret, 1,
+				lprintf(wtperf, ret, 1,
 				    "%s for: %s, range: %"PRIu64, op_name(op),
-				    key_buf, wtperf_value_range(cfg));
+				    key_buf, wtperf_value_range(wtperf));
 				if ((ret = session->rollback_transaction(
 				    session, NULL)) != 0) {
-					lprintf(cfg, ret, 0,
+					lprintf(wtperf, ret, 0,
 					     "Failed rollback_transaction");
 					goto err;
 				}
 				if ((ret = session->begin_transaction(
 				    session, NULL)) != 0) {
-					lprintf(cfg, ret, 0,
+					lprintf(wtperf, ret, 0,
 					    "Worker begin transaction failed");
 					goto err;
 				}
 				break;
 			}
-			lprintf(cfg, ret, 0,
+			lprintf(wtperf, ret, 0,
 			    "%s failed for: %s, range: %"PRIu64,
-			    op_name(op), key_buf, wtperf_value_range(cfg));
+			    op_name(op), key_buf, wtperf_value_range(wtperf));
 			goto err;
 		default:
 			goto err;		/* can't happen */
 		}
 
 		/* Update the log-like table. */
-		if (cfg->log_like_table &&
+		if (opts->log_like_table &&
 		    (*op != WORKER_READ && *op != WORKER_TRUNCATE)) {
-			log_id = __wt_atomic_add64(&cfg->log_like_table_key, 1);
+			log_id =
+			    __wt_atomic_add64(&wtperf->log_like_table_key, 1);
 			log_table_cursor->set_key(log_table_cursor, log_id);
 			log_table_cursor->set_value(
 			    log_table_cursor, value_buf);
 			if ((ret =
 			    log_table_cursor->insert(log_table_cursor)) != 0) {
-				lprintf(cfg, ret, 0, "Cursor insert failed");
+				lprintf(wtperf, ret, 0, "Cursor insert failed");
 				goto err;
 			}
 		}
 
 		/* Release the cursor, if we have multiple tables. */
-		if (cfg->table_count > 1 && ret == 0 &&
+		if (opts->table_count > 1 && ret == 0 &&
 		    *op != WORKER_INSERT && *op != WORKER_INSERT_RMW) {
 			if ((ret = cursor->reset(cursor)) != 0) {
-				lprintf(cfg, ret, 0, "Cursor reset failed");
+				lprintf(wtperf, ret, 0, "Cursor reset failed");
 				goto err;
 			}
 		}
 
 		/* Gather statistics */
-		if (!cfg->in_warmup) {
+		if (!wtperf->in_warmup) {
 			if (measure_latency) {
-				if ((ret = __wt_epoch(NULL, &stop)) != 0) {
-					lprintf(cfg, ret, 0,
-					    "Get time call failed");
-					goto err;
-				}
+				__wt_epoch(NULL, &stop);
 				++trk->latency_ops;
 				usecs = WT_TIMEDIFF_US(stop, start);
 				track_operation(trk, usecs);
@@ -824,17 +788,17 @@ op_err:			if (ret == WT_ROLLBACK && ops_per_txn != 0) {
 		 * Commit the transaction if grouping operations together
 		 * or tracking changes in our log table.
 		 */
-		if ((cfg->log_like_table && ops_per_txn == 0) ||
+		if ((opts->log_like_table && ops_per_txn == 0) ||
 		    (ops_per_txn != 0 && ops++ % ops_per_txn == 0)) {
 			if ((ret = session->commit_transaction(
 			    session, NULL)) != 0) {
-				lprintf(cfg, ret, 0,
+				lprintf(wtperf, ret, 0,
 				    "Worker transaction commit failed");
 				goto err;
 			}
 			if ((ret = session->begin_transaction(
 			    session, NULL)) != 0) {
-				lprintf(cfg, ret, 0,
+				lprintf(wtperf, ret, 0,
 				    "Worker begin transaction failed");
 				goto err;
 			}
@@ -854,13 +818,13 @@ op_err:			if (ret == WT_ROLLBACK && ops_per_txn != 0) {
 	}
 
 	if ((ret = session->close(session, NULL)) != 0) {
-		lprintf(cfg, ret, 0, "Session close in worker failed");
+		lprintf(wtperf, ret, 0, "Session close in worker failed");
 		goto err;
 	}
 
 	/* Notify our caller we failed and shut the system down. */
 	if (0) {
-err:		cfg->error = cfg->stop = 1;
+err:		wtperf->error = wtperf->stop = true;
 	}
 	free(cursors);
 
@@ -913,14 +877,17 @@ run_mix_schedule_op(WORKLOAD *workp, int op, int64_t op_cnt)
  *	Schedule the mixed-run operations.
  */
 static int
-run_mix_schedule(CONFIG *cfg, WORKLOAD *workp)
+run_mix_schedule(WTPERF *wtperf, WORKLOAD *workp)
 {
+	CONFIG_OPTS *opts;
 	int64_t pct;
 
+	opts = wtperf->opts;
+
 	/* Confirm reads, inserts, truncates and updates cannot all be zero. */
 	if (workp->insert == 0 && workp->read == 0 &&
 	    workp->truncate == 0 && workp->update == 0) {
-		lprintf(cfg, EINVAL, 0, "no operations scheduled");
+		lprintf(wtperf, EINVAL, 0, "no operations scheduled");
 		return (EINVAL);
 	}
 
@@ -931,7 +898,7 @@ run_mix_schedule(CONFIG *cfg, WORKLOAD *workp)
 	if (workp->truncate != 0) {
 		if (workp->insert != 0 ||
 		    workp->read != 0 || workp->update != 0) {
-			lprintf(cfg, EINVAL, 0,
+			lprintf(wtperf, EINVAL, 0,
 			    "Can't configure truncate in a mixed workload");
 			return (EINVAL);
 		}
@@ -947,7 +914,7 @@ run_mix_schedule(CONFIG *cfg, WORKLOAD *workp)
 	 */
 	if (workp->insert != 0 && workp->read == 0 && workp->update == 0) {
 		memset(workp->ops,
-		    cfg->insert_rmw ? WORKER_INSERT_RMW : WORKER_INSERT,
+		    opts->insert_rmw ? WORKER_INSERT_RMW : WORKER_INSERT,
 		    sizeof(workp->ops));
 		return (0);
 	}
@@ -979,7 +946,7 @@ run_mix_schedule(CONFIG *cfg, WORKLOAD *workp)
 	    (workp->insert + workp->read + workp->update);
 	if (pct != 0)
 		run_mix_schedule_op(workp,
-		    cfg->insert_rmw ? WORKER_INSERT_RMW : WORKER_INSERT, pct);
+		    opts->insert_rmw ? WORKER_INSERT_RMW : WORKER_INSERT, pct);
 	pct = (workp->update * 100) /
 	    (workp->insert + workp->read + workp->update);
 	if (pct != 0)
@@ -991,9 +958,10 @@ static void *
 populate_thread(void *arg)
 {
 	struct timespec start, stop;
-	CONFIG *cfg;
-	CONFIG_THREAD *thread;
+	CONFIG_OPTS *opts;
 	TRACK *trk;
+	WTPERF *wtperf;
+	WTPERF_THREAD *thread;
 	WT_CONNECTION *conn;
 	WT_CURSOR **cursors, *cursor;
 	WT_SESSION *session;
@@ -1004,9 +972,10 @@ populate_thread(void *arg)
 	char *value_buf, *key_buf;
 	const char *cursor_config;
 
-	thread = (CONFIG_THREAD *)arg;
-	cfg = thread->cfg;
-	conn = cfg->conn;
+	thread = (WTPERF_THREAD *)arg;
+	wtperf = thread->wtperf;
+	opts = wtperf->opts;
+	conn = wtperf->conn;
 	session = NULL;
 	cursors = NULL;
 	ret = stress_checkpoint_due = 0;
@@ -1016,37 +985,37 @@ populate_thread(void *arg)
 	value_buf = thread->value_buf;
 
 	if ((ret = conn->open_session(
-	    conn, NULL, cfg->sess_config, &session)) != 0) {
-		lprintf(cfg, ret, 0, "populate: WT_CONNECTION.open_session");
+	    conn, NULL, opts->sess_config, &session)) != 0) {
+		lprintf(wtperf, ret, 0, "populate: WT_CONNECTION.open_session");
 		goto err;
 	}
 
 	/* Do bulk loads if populate is single-threaded. */
 	cursor_config =
-	    (cfg->populate_threads == 1 && !cfg->index) ? "bulk" : NULL;
+	    (opts->populate_threads == 1 && !opts->index) ? "bulk" : NULL;
 	/* Create the cursors. */
-	cursors = dcalloc(cfg->table_count, sizeof(WT_CURSOR *));
-	for (i = 0; i < cfg->table_count; i++) {
+	cursors = dcalloc(opts->table_count, sizeof(WT_CURSOR *));
+	for (i = 0; i < opts->table_count; i++) {
 		if ((ret = session->open_cursor(
-		    session, cfg->uris[i], NULL,
+		    session, wtperf->uris[i], NULL,
 		    cursor_config, &cursors[i])) != 0) {
-			lprintf(cfg, ret, 0,
+			lprintf(wtperf, ret, 0,
 			    "populate: WT_SESSION.open_cursor: %s",
-			    cfg->uris[i]);
+			    wtperf->uris[i]);
 			goto err;
 		}
 	}
 
 	/* Populate the databases. */
 	for (intxn = 0, opcount = 0;;) {
-		op = get_next_incr(cfg);
-		if (op > cfg->icount)
+		op = get_next_incr(wtperf);
+		if (op > opts->icount)
 			break;
 
-		if (cfg->populate_ops_per_txn != 0 && !intxn) {
+		if (opts->populate_ops_per_txn != 0 && !intxn) {
 			if ((ret = session->begin_transaction(
-			    session, cfg->transaction_config)) != 0) {
-				lprintf(cfg, ret, 0,
+			    session, opts->transaction_config)) != 0) {
+				lprintf(wtperf, ret, 0,
 				    "Failed starting transaction.");
 				goto err;
 			}
@@ -1055,31 +1024,29 @@ populate_thread(void *arg)
 		/*
 		 * Figure out which table this op belongs to.
 		 */
-		cursor = cursors[map_key_to_table(cfg, op)];
-		generate_key(cfg, key_buf, op);
+		cursor = cursors[map_key_to_table(wtperf->opts, op)];
+		generate_key(opts, key_buf, op);
 		measure_latency =
-		    cfg->sample_interval != 0 &&
-		    trk->ops != 0 && (trk->ops % cfg->sample_rate == 0);
-		if (measure_latency && (ret = __wt_epoch(NULL, &start)) != 0) {
-			lprintf(cfg, ret, 0, "Get time call failed");
-			goto err;
-		}
+		    opts->sample_interval != 0 &&
+		    trk->ops != 0 && (trk->ops % opts->sample_rate == 0);
+		if (measure_latency)
+			__wt_epoch(NULL, &start);
 		cursor->set_key(cursor, key_buf);
-		if (cfg->random_value)
+		if (opts->random_value)
 			randomize_value(thread, value_buf);
 		cursor->set_value(cursor, value_buf);
 		if ((ret = cursor->insert(cursor)) == WT_ROLLBACK) {
-			lprintf(cfg, ret, 0, "insert retrying");
+			lprintf(wtperf, ret, 0, "insert retrying");
 			if ((ret = session->rollback_transaction(
 			    session, NULL)) != 0) {
-				lprintf(cfg, ret, 0,
+				lprintf(wtperf, ret, 0,
 				    "Failed rollback_transaction");
 				goto err;
 			}
 			intxn = 0;
 			continue;
 		} else if (ret != 0) {
-			lprintf(cfg, ret, 0, "Failed inserting");
+			lprintf(wtperf, ret, 0, "Failed inserting");
 			goto err;
 		}
 		/*
@@ -1089,28 +1056,25 @@ populate_thread(void *arg)
 		 * of them.
 		 */
 		if (measure_latency) {
-			if ((ret = __wt_epoch(NULL, &stop)) != 0) {
-				lprintf(cfg, ret, 0, "Get time call failed");
-				goto err;
-			}
+			__wt_epoch(NULL, &stop);
 			++trk->latency_ops;
 			usecs = WT_TIMEDIFF_US(stop, start);
 			track_operation(trk, usecs);
 		}
 		++thread->insert.ops;	/* Same as trk->ops */
 
-		if (cfg->checkpoint_stress_rate != 0 &&
-		    (op % cfg->checkpoint_stress_rate) == 0)
+		if (opts->checkpoint_stress_rate != 0 &&
+		    (op % opts->checkpoint_stress_rate) == 0)
 			stress_checkpoint_due = 1;
 
-		if (cfg->populate_ops_per_txn != 0) {
-			if (++opcount < cfg->populate_ops_per_txn)
+		if (opts->populate_ops_per_txn != 0) {
+			if (++opcount < opts->populate_ops_per_txn)
 				continue;
 			opcount = 0;
 
 			if ((ret = session->commit_transaction(
 			    session, NULL)) != 0)
-				lprintf(cfg, ret, 0,
+				lprintf(wtperf, ret, 0,
 				    "Fail committing, transaction was aborted");
 			intxn = 0;
 		}
@@ -1118,24 +1082,24 @@ populate_thread(void *arg)
 		if (stress_checkpoint_due && intxn == 0) {
 			stress_checkpoint_due = 0;
 			if ((ret = session->checkpoint(session, NULL)) != 0) {
-				lprintf(cfg, ret, 0, "Checkpoint failed");
+				lprintf(wtperf, ret, 0, "Checkpoint failed");
 				goto err;
 			}
 		}
 	}
 	if (intxn &&
 	    (ret = session->commit_transaction(session, NULL)) != 0)
-		lprintf(cfg, ret, 0,
+		lprintf(wtperf, ret, 0,
 		    "Fail committing, transaction was aborted");
 
 	if ((ret = session->close(session, NULL)) != 0) {
-		lprintf(cfg, ret, 0, "Error closing session in populate");
+		lprintf(wtperf, ret, 0, "Error closing session in populate");
 		goto err;
 	}
 
 	/* Notify our caller we failed and shut the system down. */
 	if (0) {
-err:		cfg->error = cfg->stop = 1;
+err:		wtperf->error = wtperf->stop = true;
 	}
 	free(cursors);
 
@@ -1146,9 +1110,10 @@ static void *
 populate_async(void *arg)
 {
 	struct timespec start, stop;
-	CONFIG *cfg;
-	CONFIG_THREAD *thread;
+	CONFIG_OPTS *opts;
 	TRACK *trk;
+	WTPERF *wtperf;
+	WTPERF_THREAD *thread;
 	WT_ASYNC_OP *asyncop;
 	WT_CONNECTION *conn;
 	WT_SESSION *session;
@@ -1156,9 +1121,10 @@ populate_async(void *arg)
 	int measure_latency, ret;
 	char *value_buf, *key_buf;
 
-	thread = (CONFIG_THREAD *)arg;
-	cfg = thread->cfg;
-	conn = cfg->conn;
+	thread = (WTPERF_THREAD *)arg;
+	wtperf = thread->wtperf;
+	opts = wtperf->opts;
+	conn = wtperf->conn;
 	session = NULL;
 	ret = 0;
 	trk = &thread->insert;
@@ -1167,8 +1133,8 @@ populate_async(void *arg)
 	value_buf = thread->value_buf;
 
 	if ((ret = conn->open_session(
-	    conn, NULL, cfg->sess_config, &session)) != 0) {
-		lprintf(cfg, ret, 0, "populate: WT_CONNECTION.open_session");
+	    conn, NULL, opts->sess_config, &session)) != 0) {
+		lprintf(wtperf, ret, 0, "populate: WT_CONNECTION.open_session");
 		goto err;
 	}
 
@@ -1178,38 +1144,38 @@ populate_async(void *arg)
 	 * the time to process by workers.
 	 */
 	measure_latency =
-	    cfg->sample_interval != 0 &&
-	    trk->ops != 0 && (trk->ops % cfg->sample_rate == 0);
-	if (measure_latency && (ret = __wt_epoch(NULL, &start)) != 0) {
-		lprintf(cfg, ret, 0, "Get time call failed");
-		goto err;
-	}
+	    opts->sample_interval != 0 &&
+	    trk->ops != 0 && (trk->ops % opts->sample_rate == 0);
+	if (measure_latency)
+		__wt_epoch(NULL, &start);
+
 	/* Populate the databases. */
 	for (;;) {
-		op = get_next_incr(cfg);
-		if (op > cfg->icount)
+		op = get_next_incr(wtperf);
+		if (op > opts->icount)
 			break;
 		/*
 		 * Allocate an async op for whichever table.
 		 */
 		while ((ret = conn->async_new_op(
-		    conn, cfg->uris[map_key_to_table(cfg, op)],
+		    conn, wtperf->uris[map_key_to_table(wtperf->opts, op)],
 		    NULL, &cb, &asyncop)) == EBUSY)
 			(void)usleep(10000);
 		if (ret != 0)
 			goto err;
 
 		asyncop->app_private = thread;
-		generate_key(cfg, key_buf, op);
+		generate_key(opts, key_buf, op);
 		asyncop->set_key(asyncop, key_buf);
-		if (cfg->random_value)
+		if (opts->random_value)
 			randomize_value(thread, value_buf);
 		asyncop->set_value(asyncop, value_buf);
 		if ((ret = asyncop->insert(asyncop)) != 0) {
-			lprintf(cfg, ret, 0, "Failed inserting");
+			lprintf(wtperf, ret, 0, "Failed inserting");
 			goto err;
 		}
 	}
+
 	/*
 	 * Gather statistics.
 	 * We measure the latency of inserting a single key.  If there
@@ -1221,22 +1187,19 @@ populate_async(void *arg)
 	if (conn->async_flush(conn) != 0)
 		goto err;
 	if (measure_latency) {
-		if ((ret = __wt_epoch(NULL, &stop)) != 0) {
-			lprintf(cfg, ret, 0, "Get time call failed");
-			goto err;
-		}
+		__wt_epoch(NULL, &stop);
 		++trk->latency_ops;
 		usecs = WT_TIMEDIFF_US(stop, start);
 		track_operation(trk, usecs);
 	}
 	if ((ret = session->close(session, NULL)) != 0) {
-		lprintf(cfg, ret, 0, "Error closing session in populate");
+		lprintf(wtperf, ret, 0, "Error closing session in populate");
 		goto err;
 	}
 
 	/* Notify our caller we failed and shut the system down. */
 	if (0) {
-err:		cfg->error = cfg->stop = 1;
+err:		wtperf->error = wtperf->stop = true;
 	}
 	return (NULL);
 }
@@ -1246,8 +1209,9 @@ monitor(void *arg)
 {
 	struct timespec t;
 	struct tm *tm, _tm;
-	CONFIG *cfg;
+	CONFIG_OPTS *opts;
 	FILE *fp;
+	WTPERF *wtperf;
 	size_t len;
 	uint64_t min_thr, reads, inserts, updates;
 	uint64_t cur_reads, cur_inserts, cur_updates;
@@ -1257,24 +1221,26 @@ monitor(void *arg)
 	uint32_t update_avg, update_min, update_max;
 	uint32_t latency_max, level;
 	u_int i;
-	int msg_err, ret;
+	int msg_err;
 	const char *str;
 	char buf[64], *path;
 
-	cfg = (CONFIG *)arg;
-	assert(cfg->sample_interval != 0);
+	wtperf = (WTPERF *)arg;
+	opts = wtperf->opts;
+	assert(opts->sample_interval != 0);
+
 	fp = NULL;
 	path = NULL;
 
-	min_thr = (uint64_t)cfg->min_throughput;
-	latency_max = (uint32_t)ms_to_us(cfg->max_latency);
+	min_thr = (uint64_t)opts->min_throughput;
+	latency_max = (uint32_t)ms_to_us(opts->max_latency);
 
 	/* Open the logging file. */
-	len = strlen(cfg->monitor_dir) + 100;
+	len = strlen(wtperf->monitor_dir) + 100;
 	path = dmalloc(len);
-	snprintf(path, len, "%s/monitor", cfg->monitor_dir);
+	snprintf(path, len, "%s/monitor", wtperf->monitor_dir);
 	if ((fp = fopen(path, "w")) == NULL) {
-		lprintf(cfg, errno, 0, "%s", path);
+		lprintf(wtperf, errno, 0, "%s", path);
 		goto err;
 	}
 	/* Set line buffering for monitor file. */
@@ -1297,34 +1263,31 @@ monitor(void *arg)
 	    "update maximum latency(uS)"
 	    "\n");
 	last_reads = last_inserts = last_updates = 0;
-	while (!cfg->stop) {
-		for (i = 0; i < cfg->sample_interval; i++) {
+	while (!wtperf->stop) {
+		for (i = 0; i < opts->sample_interval; i++) {
 			sleep(1);
-			if (cfg->stop)
+			if (wtperf->stop)
 				break;
 		}
 		/* If the workers are done, don't bother with a final call. */
-		if (cfg->stop)
+		if (wtperf->stop)
 			break;
-		if (cfg->in_warmup)
+		if (wtperf->in_warmup)
 			continue;
 
-		if ((ret = __wt_epoch(NULL, &t)) != 0) {
-			lprintf(cfg, ret, 0, "Get time call failed");
-			goto err;
-		}
+		__wt_epoch(NULL, &t);
 		tm = localtime_r(&t.tv_sec, &_tm);
 		(void)strftime(buf, sizeof(buf), "%b %d %H:%M:%S", tm);
 
-		reads = sum_read_ops(cfg);
-		inserts = sum_insert_ops(cfg);
-		updates = sum_update_ops(cfg);
-		latency_read(cfg, &read_avg, &read_min, &read_max);
-		latency_insert(cfg, &insert_avg, &insert_min, &insert_max);
-		latency_update(cfg, &update_avg, &update_min, &update_max);
+		reads = sum_read_ops(wtperf);
+		inserts = sum_insert_ops(wtperf);
+		updates = sum_update_ops(wtperf);
+		latency_read(wtperf, &read_avg, &read_min, &read_max);
+		latency_insert(wtperf, &insert_avg, &insert_min, &insert_max);
+		latency_update(wtperf, &update_avg, &update_min, &update_max);
 
-		cur_reads = (reads - last_reads) / cfg->sample_interval;
-		cur_updates = (updates - last_updates) / cfg->sample_interval;
+		cur_reads = (reads - last_reads) / opts->sample_interval;
+		cur_updates = (updates - last_updates) / opts->sample_interval;
 		/*
 		 * For now the only item we need to worry about changing is
 		 * inserts when we transition from the populate phase to
@@ -1334,7 +1297,7 @@ monitor(void *arg)
 			cur_inserts = 0;
 		else
 			cur_inserts =
-			    (inserts - last_inserts) / cfg->sample_interval;
+			    (inserts - last_inserts) / opts->sample_interval;
 
 		(void)fprintf(fp,
 		    "%s,%" PRIu32
@@ -1344,9 +1307,9 @@ monitor(void *arg)
 		    ",%" PRIu32 ",%" PRIu32 ",%" PRIu32
 		    ",%" PRIu32 ",%" PRIu32 ",%" PRIu32
 		    "\n",
-		    buf, cfg->totalsec,
+		    buf, wtperf->totalsec,
 		    cur_reads, cur_inserts, cur_updates,
-		    cfg->ckpt ? 'Y' : 'N',
+		    wtperf->ckpt ? 'Y' : 'N',
 		    read_avg, read_min, read_max,
 		    insert_avg, insert_min, insert_max,
 		    update_avg, update_min, update_max);
@@ -1354,7 +1317,7 @@ monitor(void *arg)
 		if (latency_max != 0 &&
 		    (read_max > latency_max || insert_max > latency_max ||
 		     update_max > latency_max)) {
-			if (cfg->max_latency_fatal) {
+			if (opts->max_latency_fatal) {
 				level = 1;
 				msg_err = WT_PANIC;
 				str = "ERROR";
@@ -1363,7 +1326,7 @@ monitor(void *arg)
 				msg_err = 0;
 				str = "WARNING";
 			}
-			lprintf(cfg, msg_err, level,
+			lprintf(wtperf, msg_err, level,
 			    "%s: max latency exceeded: threshold %" PRIu32
 			    " read max %" PRIu32 " insert max %" PRIu32
 			    " update max %" PRIu32, str, latency_max,
@@ -1373,7 +1336,7 @@ monitor(void *arg)
 		    ((cur_reads != 0 && cur_reads < min_thr) ||
 		    (cur_inserts != 0 && cur_inserts < min_thr) ||
 		    (cur_updates != 0 && cur_updates < min_thr))) {
-			if (cfg->min_throughput_fatal) {
+			if (opts->min_throughput_fatal) {
 				level = 1;
 				msg_err = WT_PANIC;
 				str = "ERROR";
@@ -1382,7 +1345,7 @@ monitor(void *arg)
 				msg_err = 0;
 				str = "WARNING";
 			}
-			lprintf(cfg, msg_err, level,
+			lprintf(wtperf, msg_err, level,
 			    "%s: minimum throughput not met: threshold %" PRIu64
 			    " reads %" PRIu64 " inserts %" PRIu64
 			    " updates %" PRIu64, str, min_thr, cur_reads,
@@ -1395,7 +1358,7 @@ monitor(void *arg)
 
 	/* Notify our caller we failed and shut the system down. */
 	if (0) {
-err:		cfg->error = cfg->stop = 1;
+err:		wtperf->error = wtperf->stop = true;
 	}
 
 	if (fp != NULL)
@@ -1408,75 +1371,73 @@ err:		cfg->error = cfg->stop = 1;
 static void *
 checkpoint_worker(void *arg)
 {
-	CONFIG *cfg;
-	CONFIG_THREAD *thread;
+	CONFIG_OPTS *opts;
+	WTPERF *wtperf;
+	WTPERF_THREAD *thread;
 	WT_CONNECTION *conn;
 	WT_SESSION *session;
 	struct timespec e, s;
 	uint32_t i;
 	int ret;
 
-	thread = (CONFIG_THREAD *)arg;
-	cfg = thread->cfg;
-	conn = cfg->conn;
+	thread = (WTPERF_THREAD *)arg;
+	wtperf = thread->wtperf;
+	opts = wtperf->opts;
+	conn = wtperf->conn;
 	session = NULL;
 
 	if ((ret = conn->open_session(
-	    conn, NULL, cfg->sess_config, &session)) != 0) {
-		lprintf(cfg, ret, 0,
+	    conn, NULL, opts->sess_config, &session)) != 0) {
+		lprintf(wtperf, ret, 0,
 		    "open_session failed in checkpoint thread.");
 		goto err;
 	}
 
-	while (!cfg->stop) {
+	while (!wtperf->stop) {
 		/* Break the sleep up, so we notice interrupts faster. */
-		for (i = 0; i < cfg->checkpoint_interval; i++) {
+		for (i = 0; i < opts->checkpoint_interval; i++) {
 			sleep(1);
-			if (cfg->stop)
+			if (wtperf->stop)
 				break;
 		}
 		/* If the workers are done, don't bother with a final call. */
-		if (cfg->stop)
+		if (wtperf->stop)
 			break;
 
-		if ((ret = __wt_epoch(NULL, &s)) != 0) {
-			lprintf(cfg, ret, 0, "Get time failed in checkpoint.");
-			goto err;
-		}
-		cfg->ckpt = 1;
+		__wt_epoch(NULL, &s);
+
+		wtperf->ckpt = true;
 		if ((ret = session->checkpoint(session, NULL)) != 0) {
-			lprintf(cfg, ret, 0, "Checkpoint failed.");
+			lprintf(wtperf, ret, 0, "Checkpoint failed.");
 			goto err;
 		}
-		cfg->ckpt = 0;
+		wtperf->ckpt = false;
 		++thread->ckpt.ops;
 
-		if ((ret = __wt_epoch(NULL, &e)) != 0) {
-			lprintf(cfg, ret, 0, "Get time failed in checkpoint.");
-			goto err;
-		}
+		__wt_epoch(NULL, &e);
 	}
 
 	if (session != NULL &&
 	    ((ret = session->close(session, NULL)) != 0)) {
-		lprintf(cfg, ret, 0,
+		lprintf(wtperf, ret, 0,
 		    "Error closing session in checkpoint worker.");
 		goto err;
 	}
 
 	/* Notify our caller we failed and shut the system down. */
 	if (0) {
-err:		cfg->error = cfg->stop = 1;
+err:		wtperf->error = wtperf->stop = true;
 	}
 
 	return (NULL);
 }
 
 static int
-execute_populate(CONFIG *cfg)
+execute_populate(WTPERF *wtperf)
 {
 	struct timespec start, stop;
-	CONFIG_THREAD *popth;
+	CONFIG_OPTS *opts;
+	WTPERF_THREAD *popth;
 	WT_ASYNC_OP *asyncop;
 	pthread_t idle_table_cycle_thread;
 	size_t i;
@@ -1486,59 +1447,57 @@ execute_populate(CONFIG *cfg)
 	int elapsed, ret;
 	void *(*pfunc)(void *);
 
-	lprintf(cfg, 0, 1,
+	opts = wtperf->opts;
+
+	lprintf(wtperf, 0, 1,
 	    "Starting %" PRIu32
 	    " populate thread(s) for %" PRIu32 " items",
-	    cfg->populate_threads, cfg->icount);
+	    opts->populate_threads, opts->icount);
 
 	/* Start cycling idle tables if configured. */
-	if ((ret = start_idle_table_cycle(cfg, &idle_table_cycle_thread)) != 0)
+	if ((ret =
+	    start_idle_table_cycle(wtperf, &idle_table_cycle_thread)) != 0)
 		return (ret);
 
-	cfg->insert_key = 0;
+	wtperf->insert_key = 0;
 
-	cfg->popthreads = dcalloc(cfg->populate_threads, sizeof(CONFIG_THREAD));
-	if (cfg->use_asyncops > 0) {
-		lprintf(cfg, 0, 1, "Starting %" PRIu32 " async thread(s)",
-		    cfg->async_threads);
+	wtperf->popthreads =
+	    dcalloc(opts->populate_threads, sizeof(WTPERF_THREAD));
+	if (wtperf->use_asyncops) {
+		lprintf(wtperf, 0, 1, "Starting %" PRIu32 " async thread(s)",
+		    opts->async_threads);
 		pfunc = populate_async;
 	} else
 		pfunc = populate_thread;
-	if ((ret = start_threads(cfg, NULL,
-	    cfg->popthreads, cfg->populate_threads, pfunc)) != 0)
+	if ((ret = start_threads(wtperf, NULL,
+	    wtperf->popthreads, opts->populate_threads, pfunc)) != 0)
 		return (ret);
 
-	if ((ret = __wt_epoch(NULL, &start)) != 0) {
-		lprintf(cfg, ret, 0, "Get time failed in populate.");
-		return (ret);
-	}
+	__wt_epoch(NULL, &start);
 	for (elapsed = 0, interval = 0, last_ops = 0;
-	    cfg->insert_key < cfg->icount && cfg->error == 0;) {
+	    wtperf->insert_key < opts->icount && !wtperf->error;) {
 		/*
 		 * Sleep for 100th of a second, report_interval is in second
 		 * granularity, each 100th increment of elapsed is a single
 		 * increment of interval.
 		 */
 		(void)usleep(10000);
-		if (cfg->report_interval == 0 || ++elapsed < 100)
+		if (opts->report_interval == 0 || ++elapsed < 100)
 			continue;
 		elapsed = 0;
-		if (++interval < cfg->report_interval)
+		if (++interval < opts->report_interval)
 			continue;
 		interval = 0;
-		cfg->totalsec += cfg->report_interval;
-		cfg->insert_ops = sum_pop_ops(cfg);
-		lprintf(cfg, 0, 1,
+		wtperf->totalsec += opts->report_interval;
+		wtperf->insert_ops = sum_pop_ops(wtperf);
+		lprintf(wtperf, 0, 1,
 		    "%" PRIu64 " populate inserts (%" PRIu64 " of %"
 		    PRIu32 ") in %" PRIu32 " secs (%" PRIu32 " total secs)",
-		    cfg->insert_ops - last_ops, cfg->insert_ops,
-		    cfg->icount, cfg->report_interval, cfg->totalsec);
-		last_ops = cfg->insert_ops;
-	}
-	if ((ret = __wt_epoch(NULL, &stop)) != 0) {
-		lprintf(cfg, ret, 0, "Get time failed in populate.");
-		return (ret);
+		    wtperf->insert_ops - last_ops, wtperf->insert_ops,
+		    opts->icount, opts->report_interval, wtperf->totalsec);
+		last_ops = wtperf->insert_ops;
 	}
+	__wt_epoch(NULL, &stop);
 
 	/*
 	 * Move popthreads aside to narrow possible race with the monitor
@@ -1546,21 +1505,22 @@ execute_populate(CONFIG *cfg)
 	 * NULL when the populate phase is finished, to know that the workload
 	 * phase has started.
 	 */
-	popth = cfg->popthreads;
-	cfg->popthreads = NULL;
-	ret = stop_threads(cfg, cfg->populate_threads, popth);
+	popth = wtperf->popthreads;
+	wtperf->popthreads = NULL;
+	ret = stop_threads(wtperf, opts->populate_threads, popth);
 	free(popth);
 	if (ret != 0)
 		return (ret);
 
 	/* Report if any worker threads didn't finish. */
-	if (cfg->error != 0) {
-		lprintf(cfg, WT_ERROR, 0,
+	if (wtperf->error) {
+		lprintf(wtperf, WT_ERROR, 0,
 		    "Populate thread(s) exited without finishing.");
 		return (WT_ERROR);
 	}
 
-	lprintf(cfg, 0, 1, "Finished load of %" PRIu32 " items", cfg->icount);
+	lprintf(wtperf,
+	    0, 1, "Finished load of %" PRIu32 " items", opts->icount);
 	msecs = WT_TIMEDIFF_MS(stop, start);
 
 	/*
@@ -1572,9 +1532,9 @@ execute_populate(CONFIG *cfg)
 		print_ops_sec = 0;
 	} else {
 		print_secs = (double)msecs / (double)MSEC_PER_SEC;
-		print_ops_sec = (uint64_t)(cfg->icount / print_secs);
+		print_ops_sec = (uint64_t)(opts->icount / print_secs);
 	}
-	lprintf(cfg, 0, 1,
+	lprintf(wtperf, 0, 1,
 	    "Load time: %.2f\n" "load ops/sec: %" PRIu64,
 	    print_secs, print_ops_sec);
 
@@ -1583,58 +1543,57 @@ execute_populate(CONFIG *cfg)
 	 * set an unlimited timeout because if we close the connection
 	 * then any in-progress compact/merge is aborted.
 	 */
-	if (cfg->compact) {
-		assert(cfg->async_threads > 0);
-		lprintf(cfg, 0, 1, "Compact after populate");
-		if ((ret = __wt_epoch(NULL, &start)) != 0) {
-			lprintf(cfg, ret, 0, "Get time failed in populate.");
-			return (ret);
-		}
-		tables = cfg->table_count;
-		for (i = 0; i < cfg->table_count; i++) {
+	if (opts->compact) {
+		assert(opts->async_threads > 0);
+		lprintf(wtperf, 0, 1, "Compact after populate");
+		__wt_epoch(NULL, &start);
+		tables = opts->table_count;
+		for (i = 0; i < opts->table_count; i++) {
 			/*
 			 * If no ops are available, retry.  Any other error,
 			 * return.
 			 */
-			 while ((ret = cfg->conn->async_new_op(cfg->conn,
-			    cfg->uris[i], "timeout=0", &cb, &asyncop)) == EBUSY)
+			 while ((ret = wtperf->conn->async_new_op(
+			     wtperf->conn, wtperf->uris[i],
+			     "timeout=0", &cb, &asyncop)) == EBUSY)
 				(void)usleep(10000);
 			if (ret != 0)
 				return (ret);
 
 			asyncop->app_private = &tables;
 			if ((ret = asyncop->compact(asyncop)) != 0) {
-				lprintf(cfg, ret, 0, "Async compact failed.");
+				lprintf(wtperf,
+				    ret, 0, "Async compact failed.");
 				return (ret);
 			}
 		}
-		if ((ret = cfg->conn->async_flush(cfg->conn)) != 0) {
-			lprintf(cfg, ret, 0, "Populate async flush failed.");
-			return (ret);
-		}
-		if ((ret = __wt_epoch(NULL, &stop)) != 0) {
-			lprintf(cfg, ret, 0, "Get time failed in populate.");
+		if ((ret = wtperf->conn->async_flush(wtperf->conn)) != 0) {
+			lprintf(wtperf, ret, 0, "Populate async flush failed.");
 			return (ret);
 		}
-		lprintf(cfg, 0, 1,
+		__wt_epoch(NULL, &stop);
+		lprintf(wtperf, 0, 1,
 		    "Compact completed in %" PRIu64 " seconds",
 		    (uint64_t)(WT_TIMEDIFF_SEC(stop, start)));
 		assert(tables == 0);
 	}
 
 	/* Stop cycling idle tables. */
-	if ((ret = stop_idle_table_cycle(cfg, idle_table_cycle_thread)) != 0)
+	if ((ret = stop_idle_table_cycle(wtperf, idle_table_cycle_thread)) != 0)
 		return (ret);
 
 	return (0);
 }
 
 static int
-close_reopen(CONFIG *cfg)
+close_reopen(WTPERF *wtperf)
 {
+	CONFIG_OPTS *opts;
 	int ret;
 
-	if (!cfg->readonly && !cfg->reopen_connection)
+	opts = wtperf->opts;
+
+	if (!opts->readonly && !opts->reopen_connection)
 		return (0);
 	/*
 	 * Reopen the connection.  We do this so that the workload phase always
@@ -1642,16 +1601,16 @@ close_reopen(CONFIG *cfg)
 	 * be identified.  This is particularly important for LSM, where the
 	 * merge algorithm is more aggressive for read-only trees.
 	 */
-	/* cfg->conn is released no matter the return value from close(). */
-	ret = cfg->conn->close(cfg->conn, NULL);
-	cfg->conn = NULL;
+	/* wtperf->conn is released no matter the return value from close(). */
+	ret = wtperf->conn->close(wtperf->conn, NULL);
+	wtperf->conn = NULL;
 	if (ret != 0) {
-		lprintf(cfg, ret, 0, "Closing the connection failed");
+		lprintf(wtperf, ret, 0, "Closing the connection failed");
 		return (ret);
 	}
 	if ((ret = wiredtiger_open(
-	    cfg->home, NULL, cfg->reopen_config, &cfg->conn)) != 0) {
-		lprintf(cfg, ret, 0, "Re-opening the connection failed");
+	    wtperf->home, NULL, wtperf->reopen_config, &wtperf->conn)) != 0) {
+		lprintf(wtperf, ret, 0, "Re-opening the connection failed");
 		return (ret);
 	}
 	/*
@@ -1660,10 +1619,10 @@ close_reopen(CONFIG *cfg)
 	 * threads looking for work that will never arrive don't affect
 	 * performance.
 	 */
-	if (cfg->compact && cfg->use_asyncops == 0) {
-		if ((ret = cfg->conn->reconfigure(
-		    cfg->conn, "async=(enabled=false)")) != 0) {
-			lprintf(cfg, ret, 0, "Reconfigure async off failed");
+	if (opts->compact && !wtperf->use_asyncops) {
+		if ((ret = wtperf->conn->reconfigure(
+		    wtperf->conn, "async=(enabled=false)")) != 0) {
+			lprintf(wtperf, ret, 0, "Reconfigure async off failed");
 			return (ret);
 		}
 	}
@@ -1671,10 +1630,11 @@ close_reopen(CONFIG *cfg)
 }
 
 static int
-execute_workload(CONFIG *cfg)
+execute_workload(WTPERF *wtperf)
 {
-	CONFIG_THREAD *threads;
+	CONFIG_OPTS *opts;
 	WORKLOAD *workp;
+	WTPERF_THREAD *threads;
 	WT_CONNECTION *conn;
 	WT_SESSION **sessions;
 	pthread_t idle_table_cycle_thread;
@@ -1685,9 +1645,11 @@ execute_workload(CONFIG *cfg)
 	int ret, t_ret;
 	void *(*pfunc)(void *);
 
-	cfg->insert_key = 0;
-	cfg->insert_ops = cfg->read_ops = cfg->truncate_ops = 0;
-	cfg->update_ops = 0;
+	opts = wtperf->opts;
+
+	wtperf->insert_key = 0;
+	wtperf->insert_ops = wtperf->read_ops = wtperf->truncate_ops = 0;
+	wtperf->update_ops = 0;
 
 	last_ckpts = last_inserts = last_reads = last_truncates = 0;
 	last_updates = 0;
@@ -1696,38 +1658,40 @@ execute_workload(CONFIG *cfg)
 	sessions = NULL;
 
 	/* Start cycling idle tables. */
-	if ((ret = start_idle_table_cycle(cfg, &idle_table_cycle_thread)) != 0)
+	if ((ret =
+	    start_idle_table_cycle(wtperf, &idle_table_cycle_thread)) != 0)
 		return (ret);
 
-	if (cfg->warmup != 0)
-		cfg->in_warmup = 1;
+	if (opts->warmup != 0)
+		wtperf->in_warmup = true;
 
 	/* Allocate memory for the worker threads. */
-	cfg->workers = dcalloc((size_t)cfg->workers_cnt, sizeof(CONFIG_THREAD));
+	wtperf->workers =
+	    dcalloc((size_t)wtperf->workers_cnt, sizeof(WTPERF_THREAD));
 
-	if (cfg->use_asyncops > 0) {
-		lprintf(cfg, 0, 1, "Starting %" PRIu32 " async thread(s)",
-		    cfg->async_threads);
+	if (wtperf->use_asyncops) {
+		lprintf(wtperf, 0, 1, "Starting %" PRIu32 " async thread(s)",
+		    opts->async_threads);
 		pfunc = worker_async;
 	} else
 		pfunc = worker;
 
-	if (cfg->session_count_idle != 0) {
-		sessions = dcalloc((size_t)cfg->session_count_idle,
+	if (opts->session_count_idle != 0) {
+		sessions = dcalloc((size_t)opts->session_count_idle,
 		    sizeof(WT_SESSION *));
-		conn = cfg->conn;
-		for (i = 0; i < cfg->session_count_idle; ++i)
-			if ((ret = conn->open_session(
-			    conn, NULL, cfg->sess_config, &sessions[i])) != 0) {
-				lprintf(cfg, ret, 0,
+		conn = wtperf->conn;
+		for (i = 0; i < opts->session_count_idle; ++i)
+			if ((ret = conn->open_session(conn,
+			    NULL, opts->sess_config, &sessions[i])) != 0) {
+				lprintf(wtperf, ret, 0,
 				    "execute_workload: idle open_session");
 				goto err;
 			}
 	}
 	/* Start each workload. */
-	for (threads = cfg->workers, i = 0,
-	    workp = cfg->workload; i < cfg->workload_cnt; ++i, ++workp) {
-		lprintf(cfg, 0, 1,
+	for (threads = wtperf->workers, i = 0,
+	    workp = wtperf->workload; i < wtperf->workload_cnt; ++i, ++workp) {
+		lprintf(wtperf, 0, 1,
 		    "Starting workload #%u: %" PRId64 " threads, inserts=%"
 		    PRId64 ", reads=%" PRId64 ", updates=%" PRId64
 		    ", truncate=%" PRId64 ", throttle=%" PRId64,
@@ -1736,25 +1700,26 @@ execute_workload(CONFIG *cfg)
 		    workp->throttle);
 
 		/* Figure out the workload's schedule. */
-		if ((ret = run_mix_schedule(cfg, workp)) != 0)
+		if ((ret = run_mix_schedule(wtperf, workp)) != 0)
 			goto err;
 
 		/* Start the workload's threads. */
 		if ((ret = start_threads(
-		    cfg, workp, threads, (u_int)workp->threads, pfunc)) != 0)
+		    wtperf, workp, threads, (u_int)workp->threads, pfunc)) != 0)
 			goto err;
 		threads += workp->threads;
 	}
 
-	if (cfg->warmup != 0) {
-		lprintf(cfg, 0, 1,
-		    "Waiting for warmup duration of %" PRIu32, cfg->warmup);
-		sleep(cfg->warmup);
-		cfg->in_warmup = 0;
+	if (opts->warmup != 0) {
+		lprintf(wtperf, 0, 1,
+		    "Waiting for warmup duration of %" PRIu32, opts->warmup);
+		sleep(opts->warmup);
+		wtperf->in_warmup = false;
 	}
 
-	for (interval = cfg->report_interval, run_time = cfg->run_time,
-	    run_ops = cfg->run_ops; cfg->error == 0;) {
+	for (interval = opts->report_interval,
+	    run_time = opts->run_time, run_ops = opts->run_ops;
+	    !wtperf->error;) {
 		/*
 		 * Sleep for one second at a time.
 		 * If we are tracking run time, check to see if we're done, and
@@ -1769,59 +1734,60 @@ execute_workload(CONFIG *cfg)
 		}
 
 		/* Sum the operations we've done. */
-		cfg->ckpt_ops = sum_ckpt_ops(cfg);
-		cfg->insert_ops = sum_insert_ops(cfg);
-		cfg->read_ops = sum_read_ops(cfg);
-		cfg->update_ops = sum_update_ops(cfg);
-		cfg->truncate_ops = sum_truncate_ops(cfg);
+		wtperf->ckpt_ops = sum_ckpt_ops(wtperf);
+		wtperf->insert_ops = sum_insert_ops(wtperf);
+		wtperf->read_ops = sum_read_ops(wtperf);
+		wtperf->update_ops = sum_update_ops(wtperf);
+		wtperf->truncate_ops = sum_truncate_ops(wtperf);
 
 		/* If we're checking total operations, see if we're done. */
 		if (run_ops != 0 && run_ops <=
-		    cfg->insert_ops + cfg->read_ops + cfg->update_ops)
+		    wtperf->insert_ops + wtperf->read_ops + wtperf->update_ops)
 			break;
 
 		/* If writing out throughput information, see if it's time. */
 		if (interval == 0 || --interval > 0)
 			continue;
-		interval = cfg->report_interval;
-		cfg->totalsec += cfg->report_interval;
+		interval = opts->report_interval;
+		wtperf->totalsec += opts->report_interval;
 
-		lprintf(cfg, 0, 1,
+		lprintf(wtperf, 0, 1,
 		    "%" PRIu64 " reads, %" PRIu64 " inserts, %" PRIu64
 		    " updates, %" PRIu64 " truncates, %" PRIu64
 		    " checkpoints in %" PRIu32 " secs (%" PRIu32 " total secs)",
-		    cfg->read_ops - last_reads,
-		    cfg->insert_ops - last_inserts,
-		    cfg->update_ops - last_updates,
-		    cfg->truncate_ops - last_truncates,
-		    cfg->ckpt_ops - last_ckpts,
-		    cfg->report_interval, cfg->totalsec);
-		last_reads = cfg->read_ops;
-		last_inserts = cfg->insert_ops;
-		last_updates = cfg->update_ops;
-		last_truncates = cfg->truncate_ops;
-		last_ckpts = cfg->ckpt_ops;
+		    wtperf->read_ops - last_reads,
+		    wtperf->insert_ops - last_inserts,
+		    wtperf->update_ops - last_updates,
+		    wtperf->truncate_ops - last_truncates,
+		    wtperf->ckpt_ops - last_ckpts,
+		    opts->report_interval, wtperf->totalsec);
+		last_reads = wtperf->read_ops;
+		last_inserts = wtperf->insert_ops;
+		last_updates = wtperf->update_ops;
+		last_truncates = wtperf->truncate_ops;
+		last_ckpts = wtperf->ckpt_ops;
 	}
 
 	/* Notify the worker threads they are done. */
-err:	cfg->stop = 1;
+err:	wtperf->stop = true;
 
 	/* Stop cycling idle tables. */
-	if ((ret = stop_idle_table_cycle(cfg, idle_table_cycle_thread)) != 0)
+	if ((ret = stop_idle_table_cycle(wtperf, idle_table_cycle_thread)) != 0)
 		return (ret);
 
-	if ((t_ret = stop_threads(
-	    cfg, (u_int)cfg->workers_cnt, cfg->workers)) != 0 && ret == 0)
+	if ((t_ret = stop_threads(wtperf,
+	    (u_int)wtperf->workers_cnt, wtperf->workers)) != 0 && ret == 0)
 		ret = t_ret;
 
 	/* Drop tables if configured to and this isn't an error path */
-	if (ret == 0 && cfg->drop_tables && (ret = drop_all_tables(cfg)) != 0)
-		lprintf(cfg, ret, 0, "Drop tables failed.");
+	if (ret == 0 &&
+	    opts->drop_tables && (ret = drop_all_tables(wtperf)) != 0)
+		lprintf(wtperf, ret, 0, "Drop tables failed.");
 
 	free(sessions);
 	/* Report if any worker threads didn't finish. */
-	if (cfg->error != 0) {
-		lprintf(cfg, WT_ERROR, 0,
+	if (wtperf->error) {
+		lprintf(wtperf, WT_ERROR, 0,
 		    "Worker thread(s) exited without finishing.");
 		if (ret == 0)
 			ret = WT_ERROR;
@@ -1834,8 +1800,9 @@ err:	cfg->stop = 1;
  * existing table.
  */
 static int
-find_table_count(CONFIG *cfg)
+find_table_count(WTPERF *wtperf)
 {
+	CONFIG_OPTS *opts;
 	WT_CONNECTION *conn;
 	WT_CURSOR *cursor;
 	WT_SESSION *session;
@@ -1843,29 +1810,30 @@ find_table_count(CONFIG *cfg)
 	int ret, t_ret;
 	char *key;
 
-	conn = cfg->conn;
+	opts = wtperf->opts;
+	conn = wtperf->conn;
 
 	max_icount = 0;
 	if ((ret = conn->open_session(
-	    conn, NULL, cfg->sess_config, &session)) != 0) {
-		lprintf(cfg, ret, 0,
+	    conn, NULL, opts->sess_config, &session)) != 0) {
+		lprintf(wtperf, ret, 0,
 		    "find_table_count: open_session failed");
 		goto out;
 	}
-	for (i = 0; i < cfg->table_count; i++) {
-		if ((ret = session->open_cursor(session, cfg->uris[i],
+	for (i = 0; i < opts->table_count; i++) {
+		if ((ret = session->open_cursor(session, wtperf->uris[i],
 		    NULL, NULL, &cursor)) != 0) {
-			lprintf(cfg, ret, 0,
+			lprintf(wtperf, ret, 0,
 			    "find_table_count: open_cursor failed");
 			goto err;
 		}
 		if ((ret = cursor->prev(cursor)) != 0) {
-			lprintf(cfg, ret, 0,
+			lprintf(wtperf, ret, 0,
 			    "find_table_count: cursor prev failed");
 			goto err;
 		}
 		if ((ret = cursor->get_key(cursor, &key)) != 0) {
-			lprintf(cfg, ret, 0,
+			lprintf(wtperf, ret, 0,
 			    "find_table_count: cursor get_key failed");
 			goto err;
 		}
@@ -1874,7 +1842,7 @@ find_table_count(CONFIG *cfg)
 			max_icount = table_icount;
 
 		if ((ret = cursor->close(cursor)) != 0) {
-			lprintf(cfg, ret, 0,
+			lprintf(wtperf, ret, 0,
 			    "find_table_count: cursor close failed");
 			goto err;
 		}
@@ -1882,91 +1850,99 @@ find_table_count(CONFIG *cfg)
 err:	if ((t_ret = session->close(session, NULL)) != 0) {
 		if (ret == 0)
 			ret = t_ret;
-		lprintf(cfg, ret, 0,
+		lprintf(wtperf, ret, 0,
 		    "find_table_count: session close failed");
 	}
-	cfg->icount = max_icount;
+	opts->icount = max_icount;
 out:	return (ret);
 }
 
 /*
- * Populate the uri array if more than one table is being used.
+ * Populate the uri array.
  */
 static void
-create_uris(CONFIG *cfg)
+create_uris(WTPERF *wtperf)
 {
-	size_t base_uri_len;
+	CONFIG_OPTS *opts;
+	size_t len;
 	uint32_t i;
-	char *uri;
 
-	base_uri_len = strlen(cfg->base_uri);
-	cfg->uris = dcalloc(cfg->table_count, sizeof(char *));
-	for (i = 0; i < cfg->table_count; i++) {
-		uri = cfg->uris[i] = dcalloc(base_uri_len + 6, 1);
-		/*
-		 * If there is only one table, just use base name.
-		 */
-		if (cfg->table_count == 1)
-			memcpy(uri, cfg->base_uri, base_uri_len);
+	opts = wtperf->opts;
+
+	wtperf->uris = dcalloc(opts->table_count, sizeof(char *));
+	len = strlen("table:") + strlen(opts->table_name) + 20;
+	for (i = 0; i < opts->table_count; i++) {
+		/* If there is only one table, just use the base name. */
+		wtperf->uris[i] = dmalloc(len);
+		if (opts->table_count == 1)
+			snprintf(wtperf->uris[i],
+			    len, "table:%s", opts->table_name);
 		else
-			sprintf(uri, "%s%05d", cfg->base_uri, i);
+			snprintf(wtperf->uris[i],
+			    len, "table:%s%05d", opts->table_name, i);
 	}
 
 	/* Create the log-like-table URI. */
-	cfg->log_table_uri = dcalloc(base_uri_len + 11, 1);
-	sprintf(cfg->log_table_uri, "%s_log_table", cfg->base_uri);
+	len = strlen("table:") +
+	    strlen(opts->table_name) + strlen("_log_table") + 1;
+	wtperf->log_table_uri = dmalloc(len);
+	snprintf(
+	    wtperf->log_table_uri, len, "table:%s_log_table", opts->table_name);
 }
 
 static int
-create_tables(CONFIG *cfg)
+create_tables(WTPERF *wtperf)
 {
+	CONFIG_OPTS *opts;
 	WT_SESSION *session;
 	size_t i;
 	int ret;
 	char buf[512];
 
-	if ((ret = cfg->conn->open_session(
-	    cfg->conn, NULL, cfg->sess_config, &session)) != 0) {
-		lprintf(cfg, ret, 0,
-		    "Error opening a session on %s", cfg->home);
+	opts = wtperf->opts;
+
+	if ((ret = wtperf->conn->open_session(
+	    wtperf->conn, NULL, opts->sess_config, &session)) != 0) {
+		lprintf(wtperf, ret, 0,
+		    "Error opening a session on %s", wtperf->home);
 		return (ret);
 	}
 
-	for (i = 0; i < cfg->table_count_idle; i++) {
-		snprintf(buf, 512, "%s_idle%05d", cfg->uris[0], (int)i);
+	for (i = 0; i < opts->table_count_idle; i++) {
+		snprintf(buf, 512, "%s_idle%05d", wtperf->uris[0], (int)i);
 		if ((ret = session->create(
-		    session, buf, cfg->table_config)) != 0) {
-			lprintf(cfg, ret, 0,
+		    session, buf, opts->table_config)) != 0) {
+			lprintf(wtperf, ret, 0,
 			    "Error creating idle table %s", buf);
 			return (ret);
 		}
 	}
-	if (cfg->log_like_table && (ret = session->create(session,
-	    cfg->log_table_uri, "key_format=Q,value_format=S")) != 0) {
-		lprintf(cfg, ret, 0, "Error creating log table %s", buf);
+	if (opts->log_like_table && (ret = session->create(session,
+	    wtperf->log_table_uri, "key_format=Q,value_format=S")) != 0) {
+		lprintf(wtperf, ret, 0, "Error creating log table %s", buf);
 		return (ret);
 	}
 
-	for (i = 0; i < cfg->table_count; i++) {
-		if (cfg->log_partial && i > 0) {
+	for (i = 0; i < opts->table_count; i++) {
+		if (opts->log_partial && i > 0) {
 			if (((ret = session->create(session,
-			    cfg->uris[i], cfg->partial_config)) != 0)) {
-				lprintf(cfg, ret, 0,
-				    "Error creating table %s", cfg->uris[i]);
+			    wtperf->uris[i], wtperf->partial_config)) != 0)) {
+				lprintf(wtperf, ret, 0,
+				    "Error creating table %s", wtperf->uris[i]);
 				return (ret);
 			}
 		} else if ((ret = session->create(
-		    session, cfg->uris[i], cfg->table_config)) != 0) {
-			lprintf(cfg, ret, 0,
-			    "Error creating table %s", cfg->uris[i]);
+		    session, wtperf->uris[i], opts->table_config)) != 0) {
+			lprintf(wtperf, ret, 0,
+			    "Error creating table %s", wtperf->uris[i]);
 			return (ret);
 		}
-		if (cfg->index) {
+		if (opts->index) {
 			snprintf(buf, 512, "index:%s:val_idx",
-			    cfg->uris[i] + strlen("table:"));
+			    wtperf->uris[i] + strlen("table:"));
 			if ((ret = session->create(
 			    session, buf, "columns=(val)")) != 0) {
-				lprintf(cfg, ret, 0,
+				lprintf(wtperf, ret, 0,
 				    "Error creating index %s", buf);
 				return (ret);
 			}
@@ -1974,76 +1950,208 @@ create_tables(CONFIG *cfg)
 	}
 
 	if ((ret = session->close(session, NULL)) != 0) {
-		lprintf(cfg, ret, 0, "Error closing session");
+		lprintf(wtperf, ret, 0, "Error closing session");
 		return (ret);
 	}
 
 	return (0);
 }
 
+/*
+ * wtperf_copy --
+ *	Create a new WTPERF structure as a duplicate of a previous one.
+ */
+static void
+wtperf_copy(const WTPERF *src, WTPERF **retp)
+{
+	CONFIG_OPTS *opts;
+	WTPERF *dest;
+	size_t i;
+
+	opts = src->opts;
+
+	dest = dcalloc(1, sizeof(WTPERF));
+
+	/*
+	 * Don't copy the home and monitor directories, they are filled in by
+	 * our caller, explicitly.
+	 */
+
+	if (src->partial_config != NULL)
+		dest->partial_config = dstrdup(src->partial_config);
+	if (src->reopen_config != NULL)
+		dest->reopen_config = dstrdup(src->reopen_config);
+
+	if (src->uris != NULL) {
+		dest->uris = dcalloc(opts->table_count, sizeof(char *));
+		for (i = 0; i < opts->table_count; i++)
+			dest->uris[i] = dstrdup(src->uris[i]);
+	}
+
+	if (src->async_config != NULL)
+		dest->async_config = dstrdup(src->async_config);
+
+	dest->ckptthreads = NULL;
+	dest->popthreads = NULL;
+
+	dest->workers = NULL;
+	dest->workers_cnt = src->workers_cnt;
+	if (src->workload_cnt != 0) {
+		dest->workload_cnt = src->workload_cnt;
+		dest->workload = dcalloc(src->workload_cnt, sizeof(WORKLOAD));
+		memcpy(dest->workload,
+		    src->workload, src->workload_cnt * sizeof(WORKLOAD));
+	}
+
+	TAILQ_INIT(&dest->stone_head);
+
+	dest->opts = src->opts;
+
+	*retp = dest;
+}
+
+/*
+ * wtperf_free --
+ *	Free any storage allocated in the WTPERF structure.
+ */
+static void
+wtperf_free(WTPERF *wtperf)
+{
+	CONFIG_OPTS *opts;
+	size_t i;
+
+	opts = wtperf->opts;
+
+	free(wtperf->home);
+	free(wtperf->monitor_dir);
+	free(wtperf->partial_config);
+	free(wtperf->reopen_config);
+	free(wtperf->log_table_uri);
+
+	if (wtperf->uris != NULL) {
+		for (i = 0; i < opts->table_count; i++)
+			free(wtperf->uris[i]);
+		free(wtperf->uris);
+	}
+
+	free(wtperf->async_config);
+
+	free(wtperf->ckptthreads);
+	free(wtperf->popthreads);
+
+	free(wtperf->workers);
+	free(wtperf->workload);
+
+	cleanup_truncate_config(wtperf);
+}
+
+/*
+ * config_compress --
+ *	Parse the compression configuration.
+ */
+static int
+config_compress(WTPERF *wtperf)
+{
+	CONFIG_OPTS *opts;
+	int ret;
+	const char *s;
+
+	opts = wtperf->opts;
+	ret = 0;
+
+	s = opts->compression;
+	if (strcmp(s, "none") == 0) {
+		wtperf->compress_ext = NULL;
+		wtperf->compress_table = NULL;
+	} else if (strcmp(s, "lz4") == 0) {
+#ifndef HAVE_BUILTIN_EXTENSION_LZ4
+		wtperf->compress_ext = LZ4_EXT;
+#endif
+		wtperf->compress_table = LZ4_BLK;
+	} else if (strcmp(s, "snappy") == 0) {
+#ifndef HAVE_BUILTIN_EXTENSION_SNAPPY
+		wtperf->compress_ext = SNAPPY_EXT;
+#endif
+		wtperf->compress_table = SNAPPY_BLK;
+	} else if (strcmp(s, "zlib") == 0) {
+#ifndef HAVE_BUILTIN_EXTENSION_ZLIB
+		wtperf->compress_ext = ZLIB_EXT;
+#endif
+		wtperf->compress_table = ZLIB_BLK;
+	} else {
+		fprintf(stderr,
+	    "invalid compression configuration: %s\n", s);
+		ret = EINVAL;
+	}
+	return (ret);
+
+}
+
 static int
-start_all_runs(CONFIG *cfg)
+start_all_runs(WTPERF *wtperf)
 {
-	CONFIG *next_cfg, **configs;
+	CONFIG_OPTS *opts;
+	WTPERF *next_wtperf, **wtperfs;
 	pthread_t *threads;
-	size_t home_len, i;
+	size_t i, len;
 	int ret, t_ret;
-	char *new_home;
 
+	opts = wtperf->opts;
+	wtperfs = NULL;
 	ret = 0;
-	configs = NULL;
 
-	if (cfg->database_count == 1)
-		return (start_run(cfg));
+	if (opts->database_count == 1)
+		return (start_run(wtperf));
 
-	/* Allocate an array to hold our config struct copies. */
-	configs = dcalloc(cfg->database_count, sizeof(CONFIG *));
+	/* Allocate an array to hold our WTPERF copies. */
+	wtperfs = dcalloc(opts->database_count, sizeof(WTPERF *));
 
 	/* Allocate an array to hold our thread IDs. */
-	threads = dcalloc(cfg->database_count, sizeof(pthread_t));
-
-	home_len = strlen(cfg->home);
-	for (i = 0; i < cfg->database_count; i++) {
-		next_cfg = dcalloc(1, sizeof(CONFIG));
-		configs[i] = next_cfg;
-		config_copy(next_cfg, cfg);
-
-		/* Setup a unique home directory for each database. */
-		new_home = dmalloc(home_len + 5);
-		snprintf(new_home, home_len + 5, "%s/D%02d", cfg->home, (int)i);
-		free(next_cfg->home);
-		next_cfg->home = new_home;
-
-		/* If the monitor dir is default, update it too. */
-		if (strcmp(cfg->monitor_dir, cfg->home) == 0) {
-			free(next_cfg->monitor_dir);
-			next_cfg->monitor_dir = dstrdup(new_home);
-		}
+	threads = dcalloc(opts->database_count, sizeof(pthread_t));
 
-		/* If creating the sub-database, recreate its home */
-		if (cfg->create != 0)
-			recreate_dir(next_cfg->home);
+	for (i = 0; i < opts->database_count; i++) {
+		wtperf_copy(wtperf, &next_wtperf);
+		wtperfs[i] = next_wtperf;
+
+		/*
+		 * Set up unique home/monitor directories for each database.
+		 * Re-create the directories if creating the databases.
+		 */
+		len = strlen(wtperf->home) + 5;
+		next_wtperf->home = dmalloc(len);
+		snprintf(
+		    next_wtperf->home, len, "%s/D%02d", wtperf->home, (int)i);
+		if (opts->create != 0)
+			recreate_dir(next_wtperf->home);
+
+		len = strlen(wtperf->monitor_dir) + 5;
+		next_wtperf->monitor_dir = dmalloc(len);
+		snprintf(next_wtperf->monitor_dir,
+		    len, "%s/D%02d", wtperf->monitor_dir, (int)i);
+		if (opts->create != 0 &&
+		    strcmp(next_wtperf->home, next_wtperf->monitor_dir) != 0)
+			recreate_dir(next_wtperf->monitor_dir);
 
 		if ((ret = pthread_create(
-		    &threads[i], NULL, thread_run_wtperf, next_cfg)) != 0) {
-			lprintf(cfg, ret, 0, "Error creating thread");
+		    &threads[i], NULL, thread_run_wtperf, next_wtperf)) != 0) {
+			lprintf(wtperf, ret, 0, "Error creating thread");
 			goto err;
 		}
 	}
 
 	/* Wait for threads to finish. */
-	for (i = 0; i < cfg->database_count; i++)
+	for (i = 0; i < opts->database_count; i++)
 		if ((t_ret = pthread_join(threads[i], NULL)) != 0) {
-			lprintf(cfg, ret, 0, "Error joining thread");
+			lprintf(wtperf, ret, 0, "Error joining thread");
 			if (ret == 0)
 				ret = t_ret;
 		}
 
-err:	for (i = 0; i < cfg->database_count && configs[i] != NULL; i++) {
-		config_free(configs[i]);
-		free(configs[i]);
+err:	for (i = 0; i < opts->database_count && wtperfs[i] != NULL; i++) {
+		wtperf_free(wtperfs[i]);
+		free(wtperfs[i]);
 	}
-	free(configs);
+	free(wtperfs);
 	free(threads);
 
 	return (ret);
@@ -2053,120 +2161,124 @@ err:	for (i = 0; i < cfg->database_count && configs[i] != NULL; i++) {
 static void *
 thread_run_wtperf(void *arg)
 {
-	CONFIG *cfg;
+	WTPERF *wtperf;
 	int ret;
 
-	cfg = (CONFIG *)arg;
-	if ((ret = start_run(cfg)) != 0)
-		lprintf(cfg, ret, 0, "Run failed for: %s.", cfg->home);
+	wtperf = (WTPERF *)arg;
+	if ((ret = start_run(wtperf)) != 0)
+		lprintf(wtperf, ret, 0, "Run failed for: %s.", wtperf->home);
 	return (NULL);
 }
 
 static int
-start_run(CONFIG *cfg)
+start_run(WTPERF *wtperf)
 {
+	CONFIG_OPTS *opts;
 	pthread_t monitor_thread;
 	uint64_t total_ops;
 	uint32_t run_time;
 	int monitor_created, ret, t_ret;
 
+	opts = wtperf->opts;
 	monitor_created = ret = 0;
 					/* [-Wconditional-uninitialized] */
 	memset(&monitor_thread, 0, sizeof(monitor_thread));
 
-	if ((ret = setup_log_file(cfg)) != 0)
+	if ((ret = setup_log_file(wtperf)) != 0)
 		goto err;
 
 	if ((ret = wiredtiger_open(	/* Open the real connection. */
-	    cfg->home, NULL, cfg->conn_config, &cfg->conn)) != 0) {
-		lprintf(cfg, ret, 0, "Error connecting to %s", cfg->home);
+	    wtperf->home, NULL, opts->conn_config, &wtperf->conn)) != 0) {
+		lprintf(wtperf, ret, 0, "Error connecting to %s", wtperf->home);
 		goto err;
 	}
 
-	create_uris(cfg);
+	create_uris(wtperf);
 
 	/* If creating, create the tables. */
-	if (cfg->create != 0 && (ret = create_tables(cfg)) != 0)
+	if (opts->create != 0 && (ret = create_tables(wtperf)) != 0)
 		goto err;
 
 	/* Start the monitor thread. */
-	if (cfg->sample_interval != 0) {
+	if (opts->sample_interval != 0) {
 		if ((ret = pthread_create(
-		    &monitor_thread, NULL, monitor, cfg)) != 0) {
-			lprintf(
-			    cfg, ret, 0, "Error creating monitor thread.");
+		    &monitor_thread, NULL, monitor, wtperf)) != 0) {
+			lprintf(wtperf,
+			    ret, 0, "Error creating monitor thread.");
 			goto err;
 		}
 		monitor_created = 1;
 	}
 
 	/* If creating, populate the table. */
-	if (cfg->create != 0 && execute_populate(cfg) != 0)
+	if (opts->create != 0 && execute_populate(wtperf) != 0)
 		goto err;
 
 	/* Optional workload. */
-	if (cfg->workers_cnt != 0 &&
-	    (cfg->run_time != 0 || cfg->run_ops != 0)) {
+	if (wtperf->workers_cnt != 0 &&
+	    (opts->run_time != 0 || opts->run_ops != 0)) {
 		/*
 		 * If we have a workload, close and reopen the connection so
 		 * that LSM can detect read-only workloads.
 		 */
-		if (close_reopen(cfg) != 0)
+		if (close_reopen(wtperf) != 0)
 			goto err;
 
 		/* Didn't create, set insert count. */
-		if (cfg->create == 0 && cfg->random_range == 0 &&
-		    find_table_count(cfg) != 0)
+		if (opts->create == 0 &&
+		    opts->random_range == 0 && find_table_count(wtperf) != 0)
 			goto err;
 		/* Start the checkpoint thread. */
-		if (cfg->checkpoint_threads != 0) {
-			lprintf(cfg, 0, 1,
+		if (opts->checkpoint_threads != 0) {
+			lprintf(wtperf, 0, 1,
 			    "Starting %" PRIu32 " checkpoint thread(s)",
-			    cfg->checkpoint_threads);
-			cfg->ckptthreads = dcalloc(
-			     cfg->checkpoint_threads, sizeof(CONFIG_THREAD));
-			if (start_threads(cfg, NULL, cfg->ckptthreads,
-			    cfg->checkpoint_threads, checkpoint_worker) != 0)
+			    opts->checkpoint_threads);
+			wtperf->ckptthreads = dcalloc(
+			     opts->checkpoint_threads, sizeof(WTPERF_THREAD));
+			if (start_threads(wtperf, NULL, wtperf->ckptthreads,
+			    opts->checkpoint_threads, checkpoint_worker) != 0)
 				goto err;
 		}
 		/* Execute the workload. */
-		if ((ret = execute_workload(cfg)) != 0)
+		if ((ret = execute_workload(wtperf)) != 0)
 			goto err;
 
 		/* One final summation of the operations we've completed. */
-		cfg->read_ops = sum_read_ops(cfg);
-		cfg->insert_ops = sum_insert_ops(cfg);
-		cfg->truncate_ops = sum_truncate_ops(cfg);
-		cfg->update_ops = sum_update_ops(cfg);
-		cfg->ckpt_ops = sum_ckpt_ops(cfg);
-		total_ops = cfg->read_ops + cfg->insert_ops + cfg->update_ops;
-
-		run_time = cfg->run_time == 0 ? 1 : cfg->run_time;
-		lprintf(cfg, 0, 1,
+		wtperf->read_ops = sum_read_ops(wtperf);
+		wtperf->insert_ops = sum_insert_ops(wtperf);
+		wtperf->truncate_ops = sum_truncate_ops(wtperf);
+		wtperf->update_ops = sum_update_ops(wtperf);
+		wtperf->ckpt_ops = sum_ckpt_ops(wtperf);
+		total_ops =
+		    wtperf->read_ops + wtperf->insert_ops + wtperf->update_ops;
+
+		run_time = opts->run_time == 0 ? 1 : opts->run_time;
+		lprintf(wtperf, 0, 1,
 		    "Executed %" PRIu64 " read operations (%" PRIu64
 		    "%%) %" PRIu64 " ops/sec",
-		    cfg->read_ops, (cfg->read_ops * 100) / total_ops,
-		    cfg->read_ops / run_time);
-		lprintf(cfg, 0, 1,
+		    wtperf->read_ops, (wtperf->read_ops * 100) / total_ops,
+		    wtperf->read_ops / run_time);
+		lprintf(wtperf, 0, 1,
 		    "Executed %" PRIu64 " insert operations (%" PRIu64
 		    "%%) %" PRIu64 " ops/sec",
-		    cfg->insert_ops, (cfg->insert_ops * 100) / total_ops,
-		    cfg->insert_ops / run_time);
-		lprintf(cfg, 0, 1,
+		    wtperf->insert_ops, (wtperf->insert_ops * 100) / total_ops,
+		    wtperf->insert_ops / run_time);
+		lprintf(wtperf, 0, 1,
 		    "Executed %" PRIu64 " truncate operations (%" PRIu64
 		    "%%) %" PRIu64 " ops/sec",
-		    cfg->truncate_ops, (cfg->truncate_ops * 100) / total_ops,
-		    cfg->truncate_ops / run_time);
-		lprintf(cfg, 0, 1,
+		    wtperf->truncate_ops,
+		    (wtperf->truncate_ops * 100) / total_ops,
+		    wtperf->truncate_ops / run_time);
+		lprintf(wtperf, 0, 1,
 		    "Executed %" PRIu64 " update operations (%" PRIu64
 		    "%%) %" PRIu64 " ops/sec",
-		    cfg->update_ops, (cfg->update_ops * 100) / total_ops,
-		    cfg->update_ops / run_time);
-		lprintf(cfg, 0, 1,
+		    wtperf->update_ops, (wtperf->update_ops * 100) / total_ops,
+		    wtperf->update_ops / run_time);
+		lprintf(wtperf, 0, 1,
 		    "Executed %" PRIu64 " checkpoint operations",
-		    cfg->ckpt_ops);
+		    wtperf->ckpt_ops);
 
-		latency_print(cfg);
+		latency_print(wtperf);
 	}
 
 	if (0) {
@@ -2175,40 +2287,41 @@ err:		if (ret == 0)
 	}
 
 	/* Notify the worker threads they are done. */
-	cfg->stop = 1;
+	wtperf->stop = true;
 
-	if ((t_ret = stop_threads(cfg, 1, cfg->ckptthreads)) != 0)
+	if ((t_ret = stop_threads(wtperf, 1, wtperf->ckptthreads)) != 0)
 		if (ret == 0)
 			ret = t_ret;
 
 	if (monitor_created != 0 &&
 	    (t_ret = pthread_join(monitor_thread, NULL)) != 0) {
-		lprintf(cfg, ret, 0, "Error joining monitor thread.");
+		lprintf(wtperf, ret, 0, "Error joining monitor thread.");
 		if (ret == 0)
 			ret = t_ret;
 	}
 
-	if (cfg->conn != NULL &&
-	    (t_ret = cfg->conn->close(cfg->conn, NULL)) != 0) {
-		lprintf(cfg, t_ret, 0,
-		    "Error closing connection to %s", cfg->home);
+	if (wtperf->conn != NULL &&
+	    (t_ret = wtperf->conn->close(wtperf->conn, NULL)) != 0) {
+		lprintf(wtperf, t_ret, 0,
+		    "Error closing connection to %s", wtperf->home);
 		if (ret == 0)
 			ret = t_ret;
 	}
 
 	if (ret == 0) {
-		if (cfg->run_time == 0 && cfg->run_ops == 0)
-			lprintf(cfg, 0, 1, "Run completed");
+		if (opts->run_time == 0 && opts->run_ops == 0)
+			lprintf(wtperf, 0, 1, "Run completed");
 		else
-			lprintf(cfg, 0, 1, "Run completed: %" PRIu32 " %s",
-			    cfg->run_time == 0 ? cfg->run_ops : cfg->run_time,
-			    cfg->run_time == 0 ? "operations" : "seconds");
+			lprintf(wtperf, 0, 1, "Run completed: %" PRIu32 " %s",
+			    opts->run_time == 0 ?
+			    opts->run_ops : opts->run_time,
+			    opts->run_time == 0 ? "operations" : "seconds");
 	}
 
-	if (cfg->logf != NULL) {
-		if ((t_ret = fflush(cfg->logf)) != 0 && ret == 0)
+	if (wtperf->logf != NULL) {
+		if ((t_ret = fflush(wtperf->logf)) != 0 && ret == 0)
 			ret = t_ret;
-		if ((t_ret = fclose(cfg->logf)) != 0 && ret == 0)
+		if ((t_ret = fclose(wtperf->logf)) != 0 && ret == 0)
 			ret = t_ret;
 	}
 	return (ret);
@@ -2218,31 +2331,55 @@ extern int __wt_optind, __wt_optreset;
 extern char *__wt_optarg;
 void (*custom_die)(void) = NULL;
 
+/*
+ * usage --
+ *	wtperf usage print, no error.
+ */
+static void
+usage(void)
+{
+	printf("wtperf [-C config] "
+	    "[-H mount] [-h home] [-O file] [-o option] [-T config]\n");
+	printf("\t-C <string> additional connection configuration\n");
+	printf("\t            (added to option conn_config)\n");
+	printf("\t-H <mount> configure Helium volume mount point\n");
+	printf("\t-h <string> Wired Tiger home must exist, default WT_TEST\n");
+	printf("\t-O <file> file contains options as listed below\n");
+	printf("\t-o option=val[,option=val,...] set options listed below\n");
+	printf("\t-T <string> additional table configuration\n");
+	printf("\t            (added to option table_config)\n");
+	printf("\n");
+	config_opt_usage();
+}
+
 int
 main(int argc, char *argv[])
 {
-	CONFIG *cfg, _cfg;
+	CONFIG_OPTS *opts;
+	WTPERF *wtperf, _wtperf;
 	size_t req_len, sreq_len;
 	bool monitor_set;
 	int ch, ret;
-	const char *opts = "C:h:m:O:o:T:";
+	const char *cmdflags = "C:h:m:O:o:T:";
 	const char *config_opts;
-	char *cc_buf, *sess_cfg, *tc_buf, *user_cconfig, *user_tconfig;
+	char *cc_buf, *path, *sess_cfg, *tc_buf, *user_cconfig, *user_tconfig;
+
+	/* The first WTPERF structure (from which all others are derived). */
+	wtperf = &_wtperf;
+	memset(wtperf, 0, sizeof(*wtperf));
+	wtperf->home = dstrdup(DEFAULT_HOME);
+	wtperf->monitor_dir = dstrdup(DEFAULT_MONITOR_DIR);
+	TAILQ_INIT(&wtperf->stone_head);
+	config_opt_init(&wtperf->opts);
 
+	opts = wtperf->opts;
 	monitor_set = false;
 	ret = 0;
 	config_opts = NULL;
 	cc_buf = sess_cfg = tc_buf = user_cconfig = user_tconfig = NULL;
 
-	/* Setup the default configuration values. */
-	cfg = &_cfg;
-	memset(cfg, 0, sizeof(*cfg));
-	config_copy(cfg, &default_cfg);
-	cfg->home = dstrdup(DEFAULT_HOME);
-	cfg->monitor_dir = dstrdup(DEFAULT_MONITOR_DIR);
-
 	/* Do a basic validation of options, and home is needed before open. */
-	while ((ch = __wt_getopt("wtperf", argc, argv, opts)) != EOF)
+	while ((ch = __wt_getopt("wtperf", argc, argv, cmdflags)) != EOF)
 		switch (ch) {
 		case 'C':
 			if (user_cconfig == NULL)
@@ -2256,12 +2393,12 @@ main(int argc, char *argv[])
 			}
 			break;
 		case 'h':
-			free(cfg->home);
-			cfg->home = dstrdup(__wt_optarg);
+			free(wtperf->home);
+			wtperf->home = dstrdup(__wt_optarg);
 			break;
 		case 'm':
-			free(cfg->monitor_dir);
-			cfg->monitor_dir = dstrdup(__wt_optarg);
+			free(wtperf->monitor_dir);
+			wtperf->monitor_dir = dstrdup(__wt_optarg);
 			monitor_set = true;
 			break;
 		case 'O':
@@ -2288,47 +2425,48 @@ main(int argc, char *argv[])
 	 * monitor directory to the home dir.
 	 */
 	if (!monitor_set) {
-		free(cfg->monitor_dir);
-		cfg->monitor_dir = dstrdup(cfg->home);
+		free(wtperf->monitor_dir);
+		wtperf->monitor_dir = dstrdup(wtperf->home);
 	}
 
 	/* Parse configuration settings from configuration file. */
-	if (config_opts != NULL && config_opt_file(cfg, config_opts) != 0)
+	if (config_opts != NULL && config_opt_file(wtperf, config_opts) != 0)
 		goto einval;
 
 	/* Parse options that override values set via a configuration file. */
 	__wt_optreset = __wt_optind = 1;
-	while ((ch = __wt_getopt("wtperf", argc, argv, opts)) != EOF)
+	while ((ch = __wt_getopt("wtperf", argc, argv, cmdflags)) != EOF)
 		switch (ch) {
 		case 'o':
 			/* Allow -o key=value */
-			if (config_opt_line(cfg, __wt_optarg) != 0)
+			if (config_opt_str(wtperf, __wt_optarg) != 0)
 				goto einval;
 			break;
 		}
 
-	if (cfg->populate_threads == 0 && cfg->icount != 0) {
-		lprintf(cfg, 1, 0,
+	if (opts->populate_threads == 0 && opts->icount != 0) {
+		lprintf(wtperf, 1, 0,
 		    "Cannot have 0 populate threads when icount is set\n");
 		goto err;
 	}
 
-	cfg->async_config = NULL;
+	wtperf->async_config = NULL;
 	/*
 	 * If the user specified async_threads we use async for all ops.
 	 * If the user wants compaction, then we also enable async for
 	 * the compact operation, but not for the workloads.
 	 */
-	if (cfg->async_threads > 0) {
-		if (F_ISSET(cfg, CFG_TRUNCATE)) {
-			lprintf(cfg, 1, 0, "Cannot run truncate and async\n");
+	if (opts->async_threads > 0) {
+		if (F_ISSET(wtperf, CFG_TRUNCATE)) {
+			lprintf(wtperf,
+			    1, 0, "Cannot run truncate and async\n");
 			goto err;
 		}
-		cfg->use_asyncops = 1;
+		wtperf->use_asyncops = true;
 	}
-	if (cfg->compact && cfg->async_threads == 0)
-		cfg->async_threads = 2;
-	if (cfg->async_threads > 0) {
+	if (opts->compact && opts->async_threads == 0)
+		opts->async_threads = 2;
+	if (opts->async_threads > 0) {
 		/*
 		 * The maximum number of async threads is two digits, so just
 		 * use that to compute the space we need.  Assume the default
@@ -2336,145 +2474,133 @@ main(int argc, char *argv[])
 		 * to 4096 if needed.
 		 */
 		req_len = strlen(",async=(enabled=true,threads=)") + 4;
-		cfg->async_config = dmalloc(req_len);
-		snprintf(cfg->async_config, req_len,
+		wtperf->async_config = dmalloc(req_len);
+		snprintf(wtperf->async_config, req_len,
 		    ",async=(enabled=true,threads=%" PRIu32 ")",
-		    cfg->async_threads);
+		    opts->async_threads);
 	}
-	if ((ret = config_compress(cfg)) != 0)
+	if ((ret = config_compress(wtperf)) != 0)
 		goto err;
 
 	/* You can't have truncate on a random collection. */
-	if (F_ISSET(cfg, CFG_TRUNCATE) && cfg->random_range) {
-		lprintf(cfg, 1, 0, "Cannot run truncate and random_range\n");
+	if (F_ISSET(wtperf, CFG_TRUNCATE) && opts->random_range) {
+		lprintf(wtperf, 1, 0, "Cannot run truncate and random_range\n");
 		goto err;
 	}
 
 	/* We can't run truncate with more than one table. */
-	if (F_ISSET(cfg, CFG_TRUNCATE) && cfg->table_count > 1) {
-		lprintf(cfg, 1, 0, "Cannot truncate more than 1 table\n");
+	if (F_ISSET(wtperf, CFG_TRUNCATE) && opts->table_count > 1) {
+		lprintf(wtperf, 1, 0, "Cannot truncate more than 1 table\n");
 		goto err;
 	}
 
-	/* Build the URI from the table name. */
-	req_len = strlen("table:") + strlen(cfg->table_name) + 2;
-	cfg->base_uri = dmalloc(req_len);
-	snprintf(cfg->base_uri, req_len, "table:%s", cfg->table_name);
-
 	/* Make stdout line buffered, so verbose output appears quickly. */
 	__wt_stream_set_line_buffer(stdout);
 
 	/* Concatenate non-default configuration strings. */
-	if (cfg->verbose > 1 || user_cconfig != NULL ||
-	    cfg->session_count_idle > 0 || cfg->compress_ext != NULL ||
-	    cfg->async_config != NULL) {
-		req_len = strlen(debug_cconfig) + 3;
+	if (opts->verbose > 1 || user_cconfig != NULL ||
+	    opts->session_count_idle > 0 || wtperf->compress_ext != NULL ||
+	    wtperf->async_config != NULL) {
+		req_len = strlen(debug_cconfig) + 20;
 		if (user_cconfig != NULL)
 			req_len += strlen(user_cconfig);
-		if (cfg->async_config != NULL)
-			req_len += strlen(cfg->async_config);
-		if (cfg->compress_ext != NULL)
-			req_len += strlen(cfg->compress_ext);
-		if (cfg->session_count_idle > 0) {
+		if (wtperf->async_config != NULL)
+			req_len += strlen(wtperf->async_config);
+		if (wtperf->compress_ext != NULL)
+			req_len += strlen(wtperf->compress_ext);
+		if (opts->session_count_idle > 0) {
 			sreq_len = strlen(",session_max=") + 6;
 			req_len += sreq_len;
 			sess_cfg = dmalloc(sreq_len);
 			snprintf(sess_cfg, sreq_len,
 			    ",session_max=%" PRIu32,
-			    cfg->session_count_idle + cfg->workers_cnt +
-			    cfg->populate_threads + 10);
+			    opts->session_count_idle +
+			    wtperf->workers_cnt + opts->populate_threads + 10);
 		}
 		cc_buf = dmalloc(req_len);
-		/*
-		 * This is getting hard to parse.
-		 */
-		snprintf(cc_buf, req_len, "%s%s%s%s%s%s%s",
-		    cfg->async_config ? cfg->async_config : "",
-		    cfg->compress_ext ? cfg->compress_ext : "",
-		    cfg->verbose > 1 && strlen(debug_cconfig) ? ",": "",
-		    cfg->verbose > 1 &&
-			strlen(debug_cconfig) ? debug_cconfig : "",
-		    sess_cfg ? sess_cfg : "",
-		    user_cconfig ? ",": "",
-		    user_cconfig ? user_cconfig : "");
-		if (strlen(cc_buf))
-			if ((ret = config_opt_str(
-			    cfg, "conn_config", cc_buf)) != 0)
-				goto err;
+		snprintf(cc_buf, req_len, "%s,%s,%s,%s,%s",
+		    wtperf->async_config ? wtperf->async_config : "",
+		    wtperf->compress_ext ? wtperf->compress_ext : "",
+		    opts->verbose > 1 ? debug_cconfig : "",
+		    sess_cfg != NULL ? sess_cfg : "",
+		    user_cconfig != NULL ? user_cconfig : "");
+		if (strlen(cc_buf) && (ret =
+		    config_opt_name_value(wtperf, "conn_config", cc_buf)) != 0)
+			goto err;
 	}
-	if (cfg->verbose > 1 || cfg->index ||
-	    user_tconfig != NULL || cfg->compress_table != NULL) {
-		req_len = strlen(debug_tconfig) + 3;
+	if (opts->verbose > 1 || opts->index ||
+	    user_tconfig != NULL || wtperf->compress_table != NULL) {
+		req_len = strlen(debug_tconfig) + 20;
 		if (user_tconfig != NULL)
 			req_len += strlen(user_tconfig);
-		if (cfg->compress_table != NULL)
-			req_len += strlen(cfg->compress_table);
-		if (cfg->index)
+		if (wtperf->compress_table != NULL)
+			req_len += strlen(wtperf->compress_table);
+		if (opts->index)
 			req_len += strlen(INDEX_COL_NAMES);
 		tc_buf = dmalloc(req_len);
-		/*
-		 * This is getting hard to parse.
-		 */
-		snprintf(tc_buf, req_len, "%s%s%s%s%s%s",
-		    cfg->index ? INDEX_COL_NAMES : "",
-		    cfg->compress_table ? cfg->compress_table : "",
-		    cfg->verbose > 1 && strlen(debug_tconfig) ? ",": "",
-		    cfg->verbose > 1 &&
-			strlen(debug_tconfig) ? debug_tconfig : "",
-		    user_tconfig ? ",": "",
+		snprintf(tc_buf, req_len, "%s,%s,%s,%s",
+		    opts->index ? INDEX_COL_NAMES : "",
+		    wtperf->compress_table != NULL ?
+		    wtperf->compress_table : "",
+		    opts->verbose > 1 ? debug_tconfig : "",
 		    user_tconfig ? user_tconfig : "");
-		if (strlen(tc_buf))
-			if ((ret = config_opt_str(
-			    cfg, "table_config", tc_buf)) != 0)
-				goto err;
+		if (strlen(tc_buf) && (ret =
+		    config_opt_name_value(wtperf, "table_config", tc_buf)) != 0)
+			goto err;
 	}
-	if (cfg->log_partial && cfg->table_count > 1) {
-		req_len = strlen(cfg->table_config) +
+	if (opts->log_partial && opts->table_count > 1) {
+		req_len = strlen(opts->table_config) +
 		    strlen(LOG_PARTIAL_CONFIG) + 1;
-		cfg->partial_config = dmalloc(req_len);
-		snprintf(cfg->partial_config, req_len, "%s%s",
-		    cfg->table_config, LOG_PARTIAL_CONFIG);
+		wtperf->partial_config = dmalloc(req_len);
+		snprintf(wtperf->partial_config, req_len, "%s%s",
+		    opts->table_config, LOG_PARTIAL_CONFIG);
 	}
 	/*
 	 * Set the config for reopen.  If readonly add in that string.
 	 * If not readonly then just copy the original conn_config.
 	 */
-	if (cfg->readonly)
-		req_len = strlen(cfg->conn_config) +
+	if (opts->readonly)
+		req_len = strlen(opts->conn_config) +
 		    strlen(READONLY_CONFIG) + 1;
 	else
-		req_len = strlen(cfg->conn_config) + 1;
-	cfg->reopen_config = dmalloc(req_len);
-	if (cfg->readonly)
-		snprintf(cfg->reopen_config, req_len, "%s%s",
-		    cfg->conn_config, READONLY_CONFIG);
+		req_len = strlen(opts->conn_config) + 1;
+	wtperf->reopen_config = dmalloc(req_len);
+	if (opts->readonly)
+		snprintf(wtperf->reopen_config, req_len, "%s%s",
+		    opts->conn_config, READONLY_CONFIG);
 	else
-		snprintf(cfg->reopen_config, req_len, "%s",
-		    cfg->conn_config);
+		snprintf(wtperf->reopen_config,
+		    req_len, "%s", opts->conn_config);
 
 	/* Sanity-check the configuration. */
-	if ((ret = config_sanity(cfg)) != 0)
+	if ((ret = config_sanity(wtperf)) != 0)
 		goto err;
 
 	/* If creating, remove and re-create the home directory. */
-	if (cfg->create != 0)
-		recreate_dir(cfg->home);
+	if (opts->create != 0)
+		recreate_dir(wtperf->home);
 
 	/* Write a copy of the config. */
-	config_to_file(cfg);
+	req_len = strlen(wtperf->home) + strlen("/CONFIG.wtperf") + 1;
+	path = dmalloc(req_len);
+	snprintf(path, req_len, "%s/CONFIG.wtperf", wtperf->home);
+	config_opt_log(opts, path);
+	free(path);
 
 	/* Display the configuration. */
-	if (cfg->verbose > 1)
-		config_print(cfg);
+	if (opts->verbose > 1)
+		config_opt_print(wtperf);
 
-	if ((ret = start_all_runs(cfg)) != 0)
+	if ((ret = start_all_runs(wtperf)) != 0)
 		goto err;
 
 	if (0) {
 einval:		ret = EINVAL;
 	}
 
-err:	config_free(cfg);
+err:	wtperf_free(wtperf);
+	config_opt_cleanup(opts);
+
 	free(cc_buf);
 	free(sess_cfg);
 	free(tc_buf);
@@ -2485,26 +2611,26 @@ err:	config_free(cfg);
 }
 
 static int
-start_threads(CONFIG *cfg,
-    WORKLOAD *workp, CONFIG_THREAD *base, u_int num, void *(*func)(void *))
+start_threads(WTPERF *wtperf,
+    WORKLOAD *workp, WTPERF_THREAD *base, u_int num, void *(*func)(void *))
 {
-	CONFIG_THREAD *thread;
+	CONFIG_OPTS *opts;
+	WTPERF_THREAD *thread;
 	u_int i;
 	int ret;
 
+	opts = wtperf->opts;
+
 	/* Initialize the threads. */
 	for (i = 0, thread = base; i < num; ++i, ++thread) {
-		thread->cfg = cfg;
+		thread->wtperf = wtperf;
 		thread->workload = workp;
 
 		/*
 		 * We don't want the threads executing in lock-step, seed each
 		 * one differently.
 		 */
-		if ((ret = __wt_random_init_seed(NULL, &thread->rnd)) != 0) {
-			lprintf(cfg, ret, 0, "Error initializing RNG");
-			return (ret);
-		}
+		__wt_random_init_seed(NULL, &thread->rnd);
 
 		/*
 		 * Every thread gets a key/data buffer because we don't bother
@@ -2512,14 +2638,14 @@ start_threads(CONFIG *cfg,
 		 * don't, it's not enough memory to bother.  These buffers hold
 		 * strings: trailing NUL is included in the size.
 		 */
-		thread->key_buf = dcalloc(cfg->key_sz, 1);
-		thread->value_buf = dcalloc(cfg->value_sz_max, 1);
+		thread->key_buf = dcalloc(opts->key_sz, 1);
+		thread->value_buf = dcalloc(opts->value_sz_max, 1);
 
 		/*
 		 * Initialize and then toss in a bit of random values if needed.
 		 */
-		memset(thread->value_buf, 'a', cfg->value_sz - 1);
-		if (cfg->random_value)
+		memset(thread->value_buf, 'a', opts->value_sz - 1);
+		if (opts->random_value)
 			randomize_value(thread, thread->value_buf);
 
 		/*
@@ -2537,7 +2663,7 @@ start_threads(CONFIG *cfg,
 	for (i = 0, thread = base; i < num; ++i, ++thread)
 		if ((ret = pthread_create(
 		    &thread->handle, NULL, func, thread)) != 0) {
-			lprintf(cfg, ret, 0, "Error creating thread");
+			lprintf(wtperf, ret, 0, "Error creating thread");
 			return (ret);
 		}
 
@@ -2545,7 +2671,7 @@ start_threads(CONFIG *cfg,
 }
 
 static int
-stop_threads(CONFIG *cfg, u_int num, CONFIG_THREAD *threads)
+stop_threads(WTPERF *wtperf, u_int num, WTPERF_THREAD *threads)
 {
 	u_int i;
 	int ret;
@@ -2555,7 +2681,7 @@ stop_threads(CONFIG *cfg, u_int num, CONFIG_THREAD *threads)
 
 	for (i = 0; i < num; ++i, ++threads) {
 		if ((ret = pthread_join(threads->handle, NULL)) != 0) {
-			lprintf(cfg, ret, 0, "Error joining thread");
+			lprintf(wtperf, ret, 0, "Error joining thread");
 			return (ret);
 		}
 
@@ -2588,35 +2714,38 @@ recreate_dir(const char *name)
 }
 
 static int
-drop_all_tables(CONFIG *cfg)
+drop_all_tables(WTPERF *wtperf)
 {
 	struct timespec start, stop;
+	CONFIG_OPTS *opts;
 	WT_SESSION *session;
 	size_t i;
 	uint64_t msecs;
 	int ret, t_ret;
 
+	opts = wtperf->opts;
+
 	/* Drop any tables. */
-	if ((ret = cfg->conn->open_session(
-	    cfg->conn, NULL, cfg->sess_config, &session)) != 0) {
-		lprintf(cfg, ret, 0,
-		    "Error opening a session on %s", cfg->home);
+	if ((ret = wtperf->conn->open_session(
+	    wtperf->conn, NULL, opts->sess_config, &session)) != 0) {
+		lprintf(wtperf, ret, 0,
+		    "Error opening a session on %s", wtperf->home);
 		return (ret);
 	}
-	testutil_check(__wt_epoch(NULL, &start));
-	for (i = 0; i < cfg->table_count; i++) {
-		if ((ret = session->drop(
-		    session, cfg->uris[i], NULL)) != 0) {
-			lprintf(cfg, ret, 0,
-			    "Error dropping table %s", cfg->uris[i]);
+	__wt_epoch(NULL, &start);
+	for (i = 0; i < opts->table_count; i++) {
+		if ((ret =
+		    session->drop(session, wtperf->uris[i], NULL)) != 0) {
+			lprintf(wtperf, ret, 0,
+			    "Error dropping table %s", wtperf->uris[i]);
 			goto err;
 		}
 	}
-	testutil_check(__wt_epoch(NULL, &stop));
+	__wt_epoch(NULL, &stop);
 	msecs = WT_TIMEDIFF_MS(stop, start);
-	lprintf(cfg, 0, 1,
+	lprintf(wtperf, 0, 1,
 	    "Executed %" PRIu32 " drop operations average time %" PRIu64 "ms",
-	    cfg->table_count, msecs / cfg->table_count);
+	    opts->table_count, msecs / opts->table_count);
 
 err:	if ((t_ret = session->close(session, NULL)) != 0 && ret == 0)
 		ret = t_ret;
@@ -2624,27 +2753,34 @@ err:	if ((t_ret = session->close(session, NULL)) != 0 && ret == 0)
 }
 
 static uint64_t
-wtperf_value_range(CONFIG *cfg)
+wtperf_value_range(WTPERF *wtperf)
 {
-	if (cfg->random_range)
-		return (cfg->icount + cfg->random_range);
+	CONFIG_OPTS *opts;
+
+	opts = wtperf->opts;
+
+	if (opts->random_range)
+		return (opts->icount + opts->random_range);
 	/*
 	 * It is legal to configure a zero size populate phase, hide that
 	 * from other code by pretending the range is 1 in that case.
 	 */
-	if (cfg->icount + cfg->insert_key == 0)
+	if (opts->icount + wtperf->insert_key == 0)
 		return (1);
-	return (cfg->icount + cfg->insert_key - (u_int)(cfg->workers_cnt + 1));
+	return (opts->icount +
+	    wtperf->insert_key - (u_int)(wtperf->workers_cnt + 1));
 }
 
 static uint64_t
-wtperf_rand(CONFIG_THREAD *thread)
+wtperf_rand(WTPERF_THREAD *thread)
 {
-	CONFIG *cfg;
+	CONFIG_OPTS *opts;
+	WTPERF *wtperf;
 	double S1, S2, U;
 	uint64_t rval;
 
-	cfg = thread->cfg;
+	wtperf = thread->wtperf;
+	opts = wtperf->opts;
 
 	/*
 	 * Use WiredTiger's random number routine: it's lock-free and fairly
@@ -2653,11 +2789,11 @@ wtperf_rand(CONFIG_THREAD *thread)
 	rval = __wt_random(&thread->rnd);
 
 	/* Use Pareto distribution to give 80/20 hot/cold values. */
-	if (cfg->pareto != 0) {
+	if (opts->pareto != 0) {
 #define	PARETO_SHAPE	1.5
 		S1 = (-1 / PARETO_SHAPE);
-		S2 = wtperf_value_range(cfg) *
-		    (cfg->pareto / 100.0) * (PARETO_SHAPE - 1);
+		S2 = wtperf_value_range(wtperf) *
+		    (opts->pareto / 100.0) * (PARETO_SHAPE - 1);
 		U = 1 - (double)rval / (double)UINT32_MAX;
 		rval = (uint64_t)((pow(U, S1) - 1) * S2);
 		/*
@@ -2665,13 +2801,13 @@ wtperf_rand(CONFIG_THREAD *thread)
 		 * 2% of the time, from my testing. That will lead to the
 		 * first item in the table being "hot".
 		 */
-		if (rval > wtperf_value_range(cfg))
+		if (rval > wtperf_value_range(wtperf))
 			rval = 0;
 	}
 	/*
 	 * Wrap the key to within the expected range and avoid zero: we never
 	 * insert that key.
 	 */
-	rval = (rval % wtperf_value_range(cfg)) + 1;
+	rval = (rval % wtperf_value_range(wtperf)) + 1;
 	return (rval);
 }
diff --git a/bench/wtperf/wtperf.h b/bench/wtperf/wtperf.h
index 1bb94db2634..afce017d919 100644
--- a/bench/wtperf/wtperf.h
+++ b/bench/wtperf/wtperf.h
@@ -36,8 +36,8 @@
 
 #include "config_opt.h"
 
-typedef struct __config CONFIG;
-typedef struct __config_thread CONFIG_THREAD;
+typedef struct __wtperf WTPERF;
+typedef struct __wtperf_thread WTPERF_THREAD;
 typedef struct __truncate_queue_entry TRUNCATE_QUEUE_ENTRY;
 
 #define	EXT_PFX	",extensions=("
@@ -95,12 +95,6 @@ struct __truncate_queue_entry {
 	TAILQ_ENTRY(__truncate_queue_entry) q;
 };
 
-struct __config_queue_entry {
-	char *string;
-	TAILQ_ENTRY(__config_queue_entry) c;
-};
-typedef struct __config_queue_entry CONFIG_QUEUE_ENTRY;
-
 /* Steering for the throttle configuration */
 typedef struct {
 	struct timespec last_increment;	/* Time that we last added more ops */
@@ -111,40 +105,35 @@ typedef struct {
 
 #define	LOG_PARTIAL_CONFIG	",log=(enabled=false)"
 #define	READONLY_CONFIG		",readonly=true"
-/*
- * NOTE:  If you add any fields to this structure here, you must also add
- * an initialization in wtperf.c in the default_cfg.
- */
-struct __config {			/* Configuration structure */
+struct __wtperf {			/* Per-database structure */
 	char *home;			/* WiredTiger home */
 	char *monitor_dir;		/* Monitor output dir */
 	char *partial_config;		/* Config string for partial logging */
 	char *reopen_config;		/* Config string for conn reopen */
-	char *base_uri;			/* Object URI */
-	char *log_table_uri;		/* URI for log table */
-	char **uris;			/* URIs if multiple tables */
+	char *log_table_uri;            /* URI for log table */
+	char **uris;			/* URIs */
 
 	WT_CONNECTION *conn;		/* Database connection */
 
 	FILE *logf;			/* Logging handle */
 
-	char *async_config;		/* Config string for async */
+	char	*async_config;		/* Config string for async */
+	bool	 use_asyncops;		/* Use async operations */
 
 	const char *compress_ext;	/* Compression extension for conn */
 	const char *compress_table;	/* Compression arg to table create */
 
-	CONFIG_THREAD *ckptthreads, *popthreads;
+	WTPERF_THREAD *ckptthreads;	/* Checkpoint threads */
+	WTPERF_THREAD *popthreads;	/* Populate threads */
 
 #define	WORKLOAD_MAX	50
-	CONFIG_THREAD	*workers;	/* Worker threads */
+	WTPERF_THREAD	*workers;	/* Worker threads */
 	u_int		 workers_cnt;
 
 	WORKLOAD	*workload;	/* Workloads */
 	u_int		 workload_cnt;
 
-	uint32_t	 use_asyncops;	/* Use async operations */
 	/* State tracking variables. */
-
 	uint64_t ckpt_ops;		/* checkpoint operations */
 	uint64_t insert_ops;		/* insert operations */
 	uint64_t read_ops;		/* read operations */
@@ -154,10 +143,10 @@ struct __config {			/* Configuration structure */
 	uint64_t insert_key;		/* insert key */
 	uint64_t log_like_table_key;	/* used to allocate IDs for log table */
 
-	volatile int ckpt;		/* checkpoint in progress */
-	volatile int error;		/* thread error */
-	volatile int stop;		/* notify threads to stop */
-	volatile int in_warmup;		/* Running warmup phase */
+	volatile bool ckpt;		/* checkpoint in progress */
+	volatile bool error;		/* thread error */
+	volatile bool stop;		/* notify threads to stop */
+	volatile bool in_warmup;	/* running warmup phase */
 
 	volatile bool idle_cycle_run;	/* Signal for idle cycle thread */
 
@@ -171,13 +160,7 @@ struct __config {			/* Configuration structure */
 	/* Queue head for use with the Truncate Logic */
 	TAILQ_HEAD(__truncate_qh, __truncate_queue_entry) stone_head;
 
-	/* Queue head to save a copy of the config to be output */
-	TAILQ_HEAD(__config_qh, __config_queue_entry) config_head;
-
-	/* Fields changeable on command line are listed in wtperf_opt.i */
-#define	OPT_DECLARE_STRUCT
-#include "wtperf_opt.i"
-#undef OPT_DECLARE_STRUCT
+	CONFIG_OPTS *opts;		/* Global configuration */
 };
 
 #define	ELEMENTS(a)	(sizeof(a) / sizeof(a[0]))
@@ -237,8 +220,8 @@ typedef struct {
 	uint32_t sec[100];		/* < 1s 2s ... 100s */
 } TRACK;
 
-struct __config_thread {		/* Per-thread structure */
-	CONFIG *cfg;			/* Enclosing configuration */
+struct __wtperf_thread {		/* Per-thread structure */
+	WTPERF *wtperf;			/* Enclosing configuration */
 
 	WT_RAND_STATE rnd;		/* Random number generation state */
 
@@ -260,50 +243,45 @@ struct __config_thread {		/* Per-thread structure */
 	TRACK truncate_sleep;		/* Truncate sleep operations */
 };
 
-void	 cleanup_truncate_config(CONFIG *);
-int	 config_compress(CONFIG *);
-void	 config_free(CONFIG *);
-void	 config_copy(CONFIG *, const CONFIG *);
-int	 config_opt_file(CONFIG *, const char *);
-int	 config_opt_line(CONFIG *, const char *);
-int	 config_opt_str(CONFIG *, const char *, const char *);
-void	 config_to_file(CONFIG *);
-void	 config_consolidate(CONFIG *);
-void	 config_print(CONFIG *);
-int	 config_sanity(CONFIG *);
-void	 latency_insert(CONFIG *, uint32_t *, uint32_t *, uint32_t *);
-void	 latency_read(CONFIG *, uint32_t *, uint32_t *, uint32_t *);
-void	 latency_update(CONFIG *, uint32_t *, uint32_t *, uint32_t *);
-void	 latency_print(CONFIG *);
+void	 cleanup_truncate_config(WTPERF *);
+int	 config_opt_file(WTPERF *, const char *);
+void	 config_opt_cleanup(CONFIG_OPTS *);
+void	 config_opt_init(CONFIG_OPTS **);
+void	 config_opt_log(CONFIG_OPTS *, const char *);
+int	 config_opt_name_value(WTPERF *, const char *, const char *);
+void	 config_opt_print(WTPERF *);
+int	 config_opt_str(WTPERF *, const char *);
+void	 config_opt_usage(void);
+int	 config_sanity(WTPERF *);
+void	 latency_insert(WTPERF *, uint32_t *, uint32_t *, uint32_t *);
+void	 latency_print(WTPERF *);
+void	 latency_read(WTPERF *, uint32_t *, uint32_t *, uint32_t *);
+void	 latency_update(WTPERF *, uint32_t *, uint32_t *, uint32_t *);
 int	 run_truncate(
-    CONFIG *, CONFIG_THREAD *, WT_CURSOR *, WT_SESSION *, int *);
-int	 setup_log_file(CONFIG *);
-void	 setup_throttle(CONFIG_THREAD*);
-int	 setup_truncate(CONFIG *, CONFIG_THREAD *, WT_SESSION *);
-int	 start_idle_table_cycle(CONFIG *, pthread_t *);
-int	 stop_idle_table_cycle(CONFIG *, pthread_t);
-uint64_t sum_ckpt_ops(CONFIG *);
-uint64_t sum_insert_ops(CONFIG *);
-uint64_t sum_pop_ops(CONFIG *);
-uint64_t sum_read_ops(CONFIG *);
-uint64_t sum_truncate_ops(CONFIG *);
-uint64_t sum_update_ops(CONFIG *);
-void	 usage(void);
-void	 worker_throttle(CONFIG_THREAD*);
-
-void	 lprintf(const CONFIG *, int err, uint32_t, const char *, ...)
+	    WTPERF *, WTPERF_THREAD *, WT_CURSOR *, WT_SESSION *, int *);
+int	 setup_log_file(WTPERF *);
+void	 setup_throttle(WTPERF_THREAD *);
+int	 setup_truncate(WTPERF *, WTPERF_THREAD *, WT_SESSION *);
+int	 start_idle_table_cycle(WTPERF *, pthread_t *);
+int	 stop_idle_table_cycle(WTPERF *, pthread_t);
+void	 worker_throttle(WTPERF_THREAD *);
+uint64_t sum_ckpt_ops(WTPERF *);
+uint64_t sum_insert_ops(WTPERF *);
+uint64_t sum_pop_ops(WTPERF *);
+uint64_t sum_read_ops(WTPERF *);
+uint64_t sum_truncate_ops(WTPERF *);
+uint64_t sum_update_ops(WTPERF *);
+
+void	 lprintf(const WTPERF *, int err, uint32_t, const char *, ...)
 #if defined(__GNUC__)
 __attribute__((format (printf, 4, 5)))
 #endif
 ;
 
 static inline void
-generate_key(CONFIG *cfg, char *key_buf, uint64_t keyno)
+generate_key(CONFIG_OPTS *opts, char *key_buf, uint64_t keyno)
 {
-	/*
-	 * Don't change to snprintf, sprintf is faster in some tests.
-	 */
-	sprintf(key_buf, "%0*" PRIu64, cfg->key_sz - 1, keyno);
+	u64_to_string_zf(keyno, key_buf, opts->key_sz);
 }
 
 static inline void
diff --git a/bench/wtperf/wtperf_opt.i b/bench/wtperf/wtperf_opt.i
index 17517ffe477..5a632f26faa 100644
--- a/bench/wtperf/wtperf_opt.i
+++ b/bench/wtperf/wtperf_opt.i
@@ -38,14 +38,14 @@
 
 #ifdef OPT_DEFINE_DESC
 #define	DEF_OPT_AS_BOOL(name, initval, desc)				\
-	{ #name, desc, #initval, BOOL_TYPE, offsetof(CONFIG, name) },
+	{ #name, desc, #initval, BOOL_TYPE, offsetof(CONFIG_OPTS, name) },
 #define	DEF_OPT_AS_CONFIG_STRING(name, initval, desc)			\
 	{ #name, desc, initval, CONFIG_STRING_TYPE,                    \
-	offsetof(CONFIG, name) },
+	offsetof(CONFIG_OPTS, name) },
 #define	DEF_OPT_AS_STRING(name, initval, desc)				\
-	{ #name, desc, initval, STRING_TYPE, offsetof(CONFIG, name) },
+	{ #name, desc, initval, STRING_TYPE, offsetof(CONFIG_OPTS, name) },
 #define	DEF_OPT_AS_UINT32(name, initval, desc)				\
-	{ #name, desc, #initval, UINT32_TYPE, offsetof(CONFIG, name) },
+	{ #name, desc, #initval, UINT32_TYPE, offsetof(CONFIG_OPTS, name) },
 #endif
 
 #ifdef OPT_DEFINE_DEFAULT
@@ -57,13 +57,13 @@
 
 #ifdef OPT_DEFINE_DOXYGEN
 #define	DEF_OPT_AS_BOOL(name, initval, desc)				\
-	{ #name, desc, #initval, BOOL_TYPE, 0 },
+	OPTION #name, desc, #initval, boolean
 #define	DEF_OPT_AS_CONFIG_STRING(name, initval, desc)			\
-	{ #name, desc, initval, CONFIG_STRING_TYPE, 0 },
+	OPTION #name, desc, initval, string
 #define	DEF_OPT_AS_STRING(name, initval, desc)				\
-	{ #name, desc, initval, STRING_TYPE, 0 },
+	OPTION #name, desc, initval, string
 #define	DEF_OPT_AS_UINT32(name, initval, desc)				\
-	{ #name, desc, #initval, UINT32_TYPE, 0 },
+	OPTION #name, desc, #initval, unsigned int
 #endif
 
 /*
@@ -104,7 +104,7 @@ DEF_OPT_AS_UINT32(database_count, 1,
     "number of WiredTiger databases to use. Each database will execute the"
     " workload using a separate home directory and complete set of worker"
     " threads")
-DEF_OPT_AS_UINT32(drop_tables, 0,
+DEF_OPT_AS_BOOL(drop_tables, 0,
     "Whether to drop all tables at the end of the run, and report time taken"
     " to do the drop.")
 DEF_OPT_AS_UINT32(icount, 5000,
@@ -193,8 +193,8 @@ DEF_OPT_AS_STRING(threads, "", "workload configuration: each 'count' "
     "'updates', 'truncate', 'truncate_pct' and 'truncate_count'. There are "
     "also behavior modifiers, supported modifiers are 'ops_per_txn'")
 DEF_OPT_AS_CONFIG_STRING(transaction_config, "",
-    "transaction configuration string, relevant when populate_opts_per_txn "
-    "is nonzero")
+    "WT_SESSION.begin_transaction configuration string, applied during the "
+    "populate phase when populate_ops_per_txn is nonzero")
 DEF_OPT_AS_STRING(table_name, "test", "table name")
 DEF_OPT_AS_BOOL(truncate_single_ops, 0,
     "Implement truncate via cursor remove instead of session API")
diff --git a/bench/wtperf/wtperf_throttle.c b/bench/wtperf/wtperf_throttle.c
index e49bca00d07..d104a68175d 100644
--- a/bench/wtperf/wtperf_throttle.c
+++ b/bench/wtperf/wtperf_throttle.c
@@ -32,7 +32,7 @@
  * Put the initial config together for running a throttled workload.
  */
 void
-setup_throttle(CONFIG_THREAD *thread)
+setup_throttle(WTPERF_THREAD *thread)
 {
 	THROTTLE_CONFIG *throttle_cfg;
 
@@ -70,7 +70,7 @@ setup_throttle(CONFIG_THREAD *thread)
 	throttle_cfg->ops_count = throttle_cfg->ops_per_increment;
 
 	/* Set the first timestamp of when we incremented */
-	testutil_check(__wt_epoch(NULL, &throttle_cfg->last_increment));
+	__wt_epoch(NULL, &throttle_cfg->last_increment);
 }
 
 /*
@@ -78,7 +78,7 @@ setup_throttle(CONFIG_THREAD *thread)
  * counter to perform more operations.
  */
 void
-worker_throttle(CONFIG_THREAD *thread)
+worker_throttle(WTPERF_THREAD *thread)
 {
 	THROTTLE_CONFIG *throttle_cfg;
 	struct timespec now;
@@ -86,7 +86,7 @@ worker_throttle(CONFIG_THREAD *thread)
 
 	throttle_cfg = &thread->throttle_cfg;
 
-	testutil_check(__wt_epoch(NULL, &now));
+	__wt_epoch(NULL, &now);
 
 	/*
 	 * If we did enough operations in the current interval, sleep for
@@ -101,7 +101,7 @@ worker_throttle(CONFIG_THREAD *thread)
 		/*
 		 * After sleeping, set the interval to the current time.
 		 */
-		testutil_check(__wt_epoch(NULL, &throttle_cfg->last_increment));
+		__wt_epoch(NULL, &throttle_cfg->last_increment);
 	} else {
 		throttle_cfg->ops_count = (usecs_delta *
 		    throttle_cfg->ops_per_increment) /
diff --git a/bench/wtperf/wtperf_truncate.c b/bench/wtperf/wtperf_truncate.c
index e6ebc83c681..3fbb740d2c8 100644
--- a/bench/wtperf/wtperf_truncate.c
+++ b/bench/wtperf/wtperf_truncate.c
@@ -35,8 +35,9 @@ decode_key(char *key_buf)
 }
 
 int
-setup_truncate(CONFIG *cfg, CONFIG_THREAD *thread, WT_SESSION *session) {
-
+setup_truncate(WTPERF *wtperf, WTPERF_THREAD *thread, WT_SESSION *session)
+{
+	CONFIG_OPTS *opts;
 	TRUNCATE_CONFIG *trunc_cfg;
 	TRUNCATE_QUEUE_ENTRY *truncate_item;
 	WORKLOAD *workload;
@@ -45,13 +46,14 @@ setup_truncate(CONFIG *cfg, CONFIG_THREAD *thread, WT_SESSION *session) {
 	int ret;
 	uint64_t end_point, final_stone_gap, i, start_point;
 
+	opts = wtperf->opts;
 	end_point = final_stone_gap = start_point = 0;
 	trunc_cfg = &thread->trunc_cfg;
 	workload = thread->workload;
 
 	/* We are limited to only one table when running truncate. */
 	if ((ret = session->open_cursor(
-	    session, cfg->uris[0], NULL, NULL, &cursor)) != 0)
+	    session, wtperf->uris[0], NULL, NULL, &cursor)) != 0)
 		goto err;
 
 	/*
@@ -79,14 +81,14 @@ setup_truncate(CONFIG *cfg, CONFIG_THREAD *thread, WT_SESSION *session) {
 	 */
 	if ((ret = cursor->next(cursor)) != 0 ||
 	    (ret = cursor->get_key(cursor, &key)) != 0) {
-		lprintf(cfg, ret, 0, "truncate setup start: failed");
+		lprintf(wtperf, ret, 0, "truncate setup start: failed");
 		goto err;
 	}
 
 	start_point = decode_key(key);
 	if ((cursor->reset(cursor)) != 0 || (ret = cursor->prev(cursor)) != 0 ||
 	    (ret = cursor->get_key(cursor, &key)) != 0) {
-		lprintf(cfg, ret, 0, "truncate setup end: failed");
+		lprintf(wtperf, ret, 0, "truncate setup end: failed");
 		goto err;
 	}
 	end_point = decode_key(key);
@@ -104,12 +106,13 @@ setup_truncate(CONFIG *cfg, CONFIG_THREAD *thread, WT_SESSION *session) {
 		for (i = 1; i <= trunc_cfg->needed_stones; i++) {
 			truncate_item =
 			    dcalloc(sizeof(TRUNCATE_QUEUE_ENTRY), 1);
-			truncate_item->key = dcalloc(cfg->key_sz, 1);
+			truncate_item->key = dcalloc(opts->key_sz, 1);
 			generate_key(
-			    cfg, truncate_item->key, trunc_cfg->stone_gap * i);
+			    opts, truncate_item->key, trunc_cfg->stone_gap * i);
 			truncate_item->diff =
 			    (trunc_cfg->stone_gap * i) - trunc_cfg->last_key;
-			TAILQ_INSERT_TAIL(&cfg->stone_head, truncate_item, q);
+			TAILQ_INSERT_TAIL(
+			    &wtperf->stone_head, truncate_item, q);
 			trunc_cfg->last_key = trunc_cfg->stone_gap * i;
 			trunc_cfg->num_stones++;
 		}
@@ -117,27 +120,29 @@ setup_truncate(CONFIG *cfg, CONFIG_THREAD *thread, WT_SESSION *session) {
 	trunc_cfg->stone_gap = final_stone_gap;
 
 err:	if ((ret = cursor->close(cursor)) != 0) {
-		lprintf(cfg, ret, 0, "truncate setup: cursor close failed");
+		lprintf(wtperf, ret, 0, "truncate setup: cursor close failed");
 	}
 	return (ret);
 }
 
 int
-run_truncate(CONFIG *cfg, CONFIG_THREAD *thread,
-    WT_CURSOR *cursor, WT_SESSION *session, int *truncatedp) {
-
+run_truncate(WTPERF *wtperf, WTPERF_THREAD *thread,
+    WT_CURSOR *cursor, WT_SESSION *session, int *truncatedp)
+{
+	CONFIG_OPTS *opts;
 	TRUNCATE_CONFIG *trunc_cfg;
 	TRUNCATE_QUEUE_ENTRY *truncate_item;
 	char *next_key;
 	int ret, t_ret;
 	uint64_t used_stone_gap;
 
-	ret = 0;
+	opts = wtperf->opts;
 	trunc_cfg = &thread->trunc_cfg;
+	ret = 0;
 
 	*truncatedp = 0;
 	/* Update the total inserts */
-	trunc_cfg->total_inserts = sum_insert_ops(cfg);
+	trunc_cfg->total_inserts = sum_insert_ops(wtperf);
 	trunc_cfg->expected_total +=
 	    (trunc_cfg->total_inserts - trunc_cfg->last_total_inserts);
 	trunc_cfg->last_total_inserts = trunc_cfg->total_inserts;
@@ -170,10 +175,10 @@ run_truncate(CONFIG *cfg, CONFIG_THREAD *thread,
 	while (trunc_cfg->num_stones < trunc_cfg->needed_stones) {
 		trunc_cfg->last_key += used_stone_gap;
 		truncate_item = dcalloc(sizeof(TRUNCATE_QUEUE_ENTRY), 1);
-		truncate_item->key = dcalloc(cfg->key_sz, 1);
-		generate_key(cfg, truncate_item->key, trunc_cfg->last_key);
+		truncate_item->key = dcalloc(opts->key_sz, 1);
+		generate_key(opts, truncate_item->key, trunc_cfg->last_key);
 		truncate_item->diff = used_stone_gap;
-		TAILQ_INSERT_TAIL(&cfg->stone_head, truncate_item, q);
+		TAILQ_INSERT_TAIL(&wtperf->stone_head, truncate_item, q);
 		trunc_cfg->num_stones++;
 	}
 
@@ -182,34 +187,35 @@ run_truncate(CONFIG *cfg, CONFIG_THREAD *thread,
 	    trunc_cfg->expected_total <= thread->workload->truncate_count)
 		return (0);
 
-	truncate_item = TAILQ_FIRST(&cfg->stone_head);
+	truncate_item = TAILQ_FIRST(&wtperf->stone_head);
 	trunc_cfg->num_stones--;
-	TAILQ_REMOVE(&cfg->stone_head, truncate_item, q);
+	TAILQ_REMOVE(&wtperf->stone_head, truncate_item, q);
 
 	/*
 	 * Truncate the content via a single truncate call or a cursor walk
 	 * depending on the configuration.
 	 */
-	if (cfg->truncate_single_ops) {
+	if (opts->truncate_single_ops) {
 		while ((ret = cursor->next(cursor)) == 0) {
 			testutil_check(cursor->get_key(cursor, &next_key));
 			if (strcmp(next_key, truncate_item->key) == 0)
 				break;
 			if ((ret = cursor->remove(cursor)) != 0) {
-				lprintf(cfg, ret, 0, "Truncate remove: failed");
+				lprintf(wtperf,
+				    ret, 0, "Truncate remove: failed");
 				goto err;
 			}
 		}
 	} else {
 		cursor->set_key(cursor,truncate_item->key);
 		if ((ret = cursor->search(cursor)) != 0) {
-			lprintf(cfg, ret, 0, "Truncate search: failed");
+			lprintf(wtperf, ret, 0, "Truncate search: failed");
 			goto err;
 		}
 
 		if ((ret = session->truncate(
 		    session, NULL, NULL, cursor, NULL)) != 0) {
-			lprintf(cfg, ret, 0, "Truncate: failed");
+			lprintf(wtperf, ret, 0, "Truncate: failed");
 			goto err;
 		}
 	}
@@ -221,19 +227,20 @@ err:	free(truncate_item->key);
 	free(truncate_item);
 	t_ret = cursor->reset(cursor);
 	if (t_ret != 0)
-		lprintf(cfg, t_ret, 0, "Cursor reset failed");
+		lprintf(wtperf, t_ret, 0, "Cursor reset failed");
 	if (ret == 0 && t_ret != 0)
 		ret = t_ret;
 	return (ret);
 }
 
 void
-cleanup_truncate_config(CONFIG *cfg) {
+cleanup_truncate_config(WTPERF *wtperf)
+{
 	TRUNCATE_QUEUE_ENTRY *truncate_item;
 
-	while (!TAILQ_EMPTY(&cfg->stone_head)) {
-		truncate_item = TAILQ_FIRST(&cfg->stone_head);
-		TAILQ_REMOVE(&cfg->stone_head, truncate_item, q);
+	while (!TAILQ_EMPTY(&wtperf->stone_head)) {
+		truncate_item = TAILQ_FIRST(&wtperf->stone_head);
+		TAILQ_REMOVE(&wtperf->stone_head, truncate_item, q);
 		free(truncate_item->key);
 		free(truncate_item);
 	}
diff --git a/build_posix/configure.ac.in b/build_posix/configure.ac.in
index 608d602937d..ad00b19a3bb 100644
--- a/build_posix/configure.ac.in
+++ b/build_posix/configure.ac.in
@@ -74,7 +74,7 @@ AM_CONDITIONAL([ARM64_HOST], [test "$wt_cv_arm64" = "yes"])
 # support compiling the ASM code we have to perform the CRC checks on PowerPC.
 # To compile with clang we need to override the ASM compiler with CCAS to use
 # gcc. Unfortunately, doing the compilation in this manner means libtool can't
-# determine what tag to use for that one .S file. If we catch that we are using
+# determine what tag to use for that one .sx file. If we catch that we are using
 # two different compilers for CC and CCAS and we are on a PowerPC system we
 # overload the libtool flags to provide CC by default.
 if test "$wt_cv_powerpc" = "yes" -a "$CC" != "$CCAS"; then
diff --git a/dist/api_data.py b/dist/api_data.py
index 9781e58a807..d02d7e4b985 100644
--- a/dist/api_data.py
+++ b/dist/api_data.py
@@ -183,6 +183,12 @@ file_config = format_meta + [
         configure Huffman encoding for values.  Permitted values are
         \c "none", \c "english", \c "utf8<file>" or \c "utf16<file>".
         See @ref huffman for more information'''),
+    Config('ignore_in_memory_cache_size', 'false', r'''
+        allow update and insert operations to proceed even if the cache is
+        already at capacity. Only valid in conjunction with in-memory
+        databases. Should be used with caution - this configuration allows
+        WiredTiger to consume memory over the configured cache limit''',
+        type='boolean'),
     Config('internal_key_truncate', 'true', r'''
         configure internal key truncation, discarding unnecessary
         trailing bytes on internal keys (ignored for custom
@@ -410,13 +416,13 @@ connection_runtime_config = [
     Config('eviction_dirty_target', '5', r'''
         perform eviction in worker threads when the cache contains at least
         this much dirty content, expressed as a percentage of the total cache
-        size.  Ignored if \c in_memory is \c true''',
+        size.''',
         min=1, max=99),
     Config('eviction_dirty_trigger', '20', r'''
         trigger application threads to perform eviction when the cache contains
         at least this much dirty content, expressed as a percentage of the
         total cache size. This setting only alters behavior if it is lower than
-        eviction_trigger. Ignored if \c in_memory is \c true''',
+        eviction_trigger''',
         min=1, max=99),
     Config('eviction_target', '80', r'''
         perform eviction in worker threads when the cache contains at least
diff --git a/dist/filelist b/dist/filelist
index 19fa1122a27..32e4231c5f2 100644
--- a/dist/filelist
+++ b/dist/filelist
@@ -48,12 +48,12 @@ src/btree/row_modify.c
 src/btree/row_srch.c
 src/cache/cache_las.c
 src/checksum/arm64/crc32-arm64.c	ARM64_HOST
-src/checksum/power8/crc32.S		POWERPC_HOST
+src/checksum/power8/crc32.sx		POWERPC_HOST
 src/checksum/power8/crc32_wrapper.c	POWERPC_HOST
 src/checksum/software/checksum.c
 src/checksum/x86/crc32-x86.c		X86_HOST
 src/checksum/zseries/crc32-s390x.c	ZSERIES_HOST
-src/checksum/zseries/crc32le-vx.S	ZSERIES_HOST
+src/checksum/zseries/crc32le-vx.sx	ZSERIES_HOST
 src/config/config.c
 src/config/config_api.c
 src/config/config_check.c
diff --git a/dist/s_docs b/dist/s_docs
index e2b1d2aed11..b4f449fa093 100755
--- a/dist/s_docs
+++ b/dist/s_docs
@@ -1,7 +1,7 @@
 #! /bin/sh
 
 t=__wt.$$
-trap 'rm -f $t /tmp/__doxy' 0 1 2 3 13 15
+trap 'rm -f $t' 0 1 2 3 13 15
 
 # Skip this when building release packages: docs are built separately
 test -n "$WT_RELEASE_BUILD" && exit 0
@@ -30,18 +30,22 @@ wtperf_config()
 {
 	# The Linux ed command writes line numbers to stderr, redirect both
 	# stdout and stderr to keep things quiet.
-	cc -o /tmp/__doxy ../bench/wtperf/doxy.c &&
+	#
+	# The OS X cpp program injects line number output in the middle of lines
+	# and doesn't stringify #XXX entries; use the -E option to the compiler
+	# instead.
+	cat ../bench/wtperf/wtperf_opt.i |
+	${CC:-cc} -E -DOPT_DEFINE_DOXYGEN - | python wtperf_config.py > $t
 	(echo '/START_AUTO_GENERATED_WTPERF_CONFIGURATION/+3,/STOP_AUTO_GENERATED_WTPERF_CONFIGURATION/-1d'
 	 echo 'i'
 	 echo ''
 	 echo '.'
-	 echo ".r !/tmp/__doxy"
+	 echo ".r $t"
 	 echo 'a'
 	 echo ''
 	 echo '.'
 	 echo 'w'
-	 echo 'q') | ed ../src/docs/wtperf.dox 1>/dev/null 2>/dev/null &&
-	 rm -f /tmp/__doxy
+	 echo 'q') | ed ../src/docs/wtperf.dox 1>/dev/null 2>/dev/null
 }
 
 structurechk()
diff --git a/dist/s_string.ok b/dist/s_string.ok
index 1887cbd936f..0e99c6b9cec 100644
--- a/dist/s_string.ok
+++ b/dist/s_string.ok
@@ -18,6 +18,7 @@ ASYNC
 Addr
 Ailamaki
 Alakuijala
+Alexandrescu's
 Alloc
 Async
 Athanassoulis
@@ -372,6 +373,7 @@ WILLNEED
 WIREDTIGER
 WRLSN
 WRNOLOCK
+WTPERF
 WaitForSingleObject
 WakeAllConditionVariable
 Wconditional
@@ -1222,6 +1224,7 @@ xxxx
 xxxxx
 xxxxxx
 zalloc
+zf
 zfree
 zlib
 zu
diff --git a/dist/s_style b/dist/s_style
index 3860a23b991..8e755224ee2 100755
--- a/dist/s_style
+++ b/dist/s_style
@@ -108,7 +108,7 @@ else
 	   ! expr "$f" : 'test/.*' > /dev/null &&
 	   ! expr "$f" : '.*/utilities/.*' > /dev/null; then
 		if ! expr "$f" : '.*/os_alloc.c' > /dev/null &&
-		     egrep '[[:space:]]free[(]|[[:space:]]strdup[(]|[[:space:]]strndup[(]|[[:space:]]malloc[(]|[[:space:]]calloc[(]|[[:space:]]realloc[(]' $f > $t; then
+		     egrep '[[:space:]]free[(]|[[:space:]]strdup[(]|[[:space:]]strndup[(]|[[:space:]]malloc[(]|[[:space:]]calloc[(]|[[:space:]]realloc[(]|[[:space:]]sprintf[(]' $f > $t; then
 			test -s $t && {
 				echo "$f: call to illegal function"
 				cat $t
diff --git a/dist/stat_data.py b/dist/stat_data.py
index 5087afa44dc..8d1011b1bb3 100644
--- a/dist/stat_data.py
+++ b/dist/stat_data.py
@@ -306,6 +306,7 @@ connection_stats = [
     TxnStat('txn_checkpoint_running', 'transaction checkpoint currently running', 'no_clear,no_scale'),
     TxnStat('txn_checkpoint_scrub_target', 'transaction checkpoint scrub dirty target', 'no_clear,no_scale'),
     TxnStat('txn_checkpoint_scrub_time', 'transaction checkpoint scrub time (msecs)', 'no_clear,no_scale'),
+    TxnStat('txn_checkpoint_skipped', 'transaction checkpoints skipped because database was clean'),
     TxnStat('txn_checkpoint_time_max', 'transaction checkpoint max time (msecs)', 'no_clear,no_scale'),
     TxnStat('txn_checkpoint_time_min', 'transaction checkpoint min time (msecs)', 'no_clear,no_scale'),
     TxnStat('txn_checkpoint_time_recent', 'transaction checkpoint most recent time (msecs)', 'no_clear,no_scale'),
@@ -381,6 +382,8 @@ connection_stats = [
     ##########################################
     # Yield statistics
     ##########################################
+    YieldStat('application_cache_time', 'application thread time waiting for cache (usecs)'),
+    YieldStat('application_evict_time', 'application thread time evicting (usecs)'),
     YieldStat('page_busy_blocked', 'page acquire busy blocked'),
     YieldStat('page_forcible_evict_blocked', 'page acquire eviction blocked'),
     YieldStat('page_locked_blocked', 'page acquire locked blocked'),
diff --git a/dist/wtperf_config.py b/dist/wtperf_config.py
new file mode 100644
index 00000000000..72256ed5527
--- /dev/null
+++ b/dist/wtperf_config.py
@@ -0,0 +1,25 @@
+# Output a doxgen version of the wtperf configuration options.
+import string, sys
+
+for line in sys.stdin:
+    if not line.startswith('OPTION '):
+        continue
+
+    line = line.replace('OPTION ', '')
+    v = line.split('",')
+    v[0] = v[0].replace('"', '').strip()
+    v[1] = v[1].replace('"', '').strip()
+    v[2] = v[2].replace('"', '').strip()
+    v[3] = v[3].replace('"', '').strip()
+
+    if v[3] == 'boolean':
+        if v[2] == '0':
+            d = 'false'
+        else:
+            d = 'true'
+    elif v[3] == 'string':
+        d = '"' + v[2] + '"'
+    else:
+        d = v[2]
+    print '@par ' + v[0] + ' (' + v[3] + ', default=' + d + ')'
+    print v[1]
diff --git a/src/async/async_worker.c b/src/async/async_worker.c
index 401d0616eab..b1bc3902f7c 100644
--- a/src/async/async_worker.c
+++ b/src/async/async_worker.c
@@ -216,7 +216,7 @@ __async_worker_execop(WT_SESSION_IMPL *session, WT_ASYNC_OP_IMPL *op,
 			break;
 		case WT_AOP_NONE:
 			WT_RET_MSG(session, EINVAL,
-			    "Unknown async optype %d\n", op->optype);
+			    "Unknown async optype %d", op->optype);
 	}
 	return (0);
 }
diff --git a/src/btree/bt_cursor.c b/src/btree/bt_cursor.c
index 3690b41ead4..41ae457b0fe 100644
--- a/src/btree/bt_cursor.c
+++ b/src/btree/bt_cursor.c
@@ -1217,7 +1217,7 @@ err:	if (FLD_ISSET(S2C(session)->log_flags, WT_CONN_LOG_ENABLED))
 
 /*
  * __wt_btcur_init --
- *	Initialize an cursor used for internal purposes.
+ *	Initialize a cursor used for internal purposes.
  */
 void
 __wt_btcur_init(WT_SESSION_IMPL *session, WT_CURSOR_BTREE *cbt)
diff --git a/src/btree/bt_handle.c b/src/btree/bt_handle.c
index 9591023e163..337a3ea036f 100644
--- a/src/btree/bt_handle.c
+++ b/src/btree/bt_handle.c
@@ -271,6 +271,17 @@ __btree_conf(WT_SESSION_IMPL *session, WT_CKPT *ckpt)
 	else
 		F_CLR(btree, WT_BTREE_IN_MEMORY | WT_BTREE_NO_EVICTION);
 
+	WT_RET(__wt_config_gets(session,
+	    cfg, "ignore_in_memory_cache_size", &cval));
+	if (cval.val) {
+		if (!F_ISSET(conn, WT_CONN_IN_MEMORY))
+			WT_RET_MSG(session, EINVAL,
+			    "ignore_in_memory_cache_size setting is only valid "
+			    "with databases configured to run in-memory");
+		F_SET(btree, WT_BTREE_IGNORE_CACHE);
+	} else
+		F_CLR(btree, WT_BTREE_IGNORE_CACHE);
+
 	WT_RET(__wt_config_gets(session, cfg, "log.enabled", &cval));
 	if (cval.val)
 		F_CLR(btree, WT_BTREE_NO_LOGGING);
@@ -353,7 +364,7 @@ __btree_conf(WT_SESSION_IMPL *session, WT_CKPT *ckpt)
 	WT_RET(__wt_spin_init(session, &btree->flush_lock, "btree flush"));
 
 	btree->checkpointing = WT_CKPT_OFF;		/* Not checkpointing */
-	btree->modified = 0;				/* Clean */
+	btree->modified = false;			/* Clean */
 	btree->write_gen = ckpt->write_gen;		/* Write generation */
 
 	return (0);
diff --git a/src/btree/bt_sync.c b/src/btree/bt_sync.c
index b41179a565d..7b583bd9c1e 100644
--- a/src/btree/bt_sync.c
+++ b/src/btree/bt_sync.c
@@ -24,20 +24,20 @@ __sync_file(WT_SESSION_IMPL *session, WT_CACHE_OP syncop)
 	WT_REF *walk;
 	WT_TXN *txn;
 	uint64_t internal_bytes, internal_pages, leaf_bytes, leaf_pages;
-	uint64_t oldest_id, saved_snap_min;
+	uint64_t oldest_id, saved_pinned_id;
 	uint32_t flags;
 
 	conn = S2C(session);
 	btree = S2BT(session);
 	walk = NULL;
 	txn = &session->txn;
-	saved_snap_min = WT_SESSION_TXN_STATE(session)->snap_min;
+	saved_pinned_id = WT_SESSION_TXN_STATE(session)->pinned_id;
 	flags = WT_READ_CACHE | WT_READ_NO_GEN;
 
 	internal_bytes = leaf_bytes = 0;
 	internal_pages = leaf_pages = 0;
 	if (WT_VERBOSE_ISSET(session, WT_VERB_CHECKPOINT))
-		WT_RET(__wt_epoch(session, &start));
+		__wt_epoch(session, &start);
 
 	switch (syncop) {
 	case WT_SYNC_WRITE_LEAVES:
@@ -205,15 +205,14 @@ __sync_file(WT_SESSION_IMPL *session, WT_CACHE_OP syncop)
 	}
 
 	if (WT_VERBOSE_ISSET(session, WT_VERB_CHECKPOINT)) {
-		WT_ERR(__wt_epoch(session, &end));
+		__wt_epoch(session, &end);
 		__wt_verbose(session, WT_VERB_CHECKPOINT,
-		    "__sync_file WT_SYNC_%s wrote:\n\t %" PRIu64
-		    " bytes, %" PRIu64 " pages of leaves\n\t %" PRIu64
-		    " bytes, %" PRIu64 " pages of internal\n\t"
-		    "Took: %" PRIu64 "ms",
+		    "__sync_file WT_SYNC_%s wrote: %" PRIu64
+		    " leaf pages (%" PRIu64 "B), %" PRIu64
+		    " internal pages (%" PRIu64 "B), and took %" PRIu64 "ms",
 		    syncop == WT_SYNC_WRITE_LEAVES ?
 		    "WRITE_LEAVES" : "CHECKPOINT",
-		    leaf_bytes, leaf_pages, internal_bytes, internal_pages,
+		    leaf_pages, leaf_bytes, internal_pages, internal_bytes,
 		    WT_TIMEDIFF_MS(end, start));
 	}
 
@@ -226,7 +225,7 @@ err:	/* On error, clear any left-over tree walk. */
 	 * snapshot active when we started, release it.
 	 */
 	if (txn->isolation == WT_ISO_READ_COMMITTED &&
-	    saved_snap_min == WT_TXN_NONE)
+	    saved_pinned_id == WT_TXN_NONE)
 		__wt_txn_release_snapshot(session);
 
 	/* Clear the checkpoint flag and push the change. */
diff --git a/src/checksum/power8/README.md b/src/checksum/power8/README.md
index 3e2976650cd..579d841a02c 100644
--- a/src/checksum/power8/README.md
+++ b/src/checksum/power8/README.md
@@ -39,7 +39,7 @@ Quick start
 
 - Type make to create the constants (crc32_constants.h)
 
-- Import the code into your application (crc32.S crc32_wrapper.c
+- Import the code into your application (crc32.sx crc32_wrapper.c
   crc32_constants.h ppc-opcode.h) and call the CRC:
 
 ```
diff --git a/src/checksum/power8/crc32.S b/src/checksum/power8/crc32.sx
index 0b7870668b5..0b7870668b5 100644
--- a/src/checksum/power8/crc32.S
+++ b/src/checksum/power8/crc32.sx
diff --git a/src/checksum/zseries/crc32le-vx.S b/src/checksum/zseries/crc32le-vx.sx
index 0f1392b0952..0f1392b0952 100644
--- a/src/checksum/zseries/crc32le-vx.S
+++ b/src/checksum/zseries/crc32le-vx.sx
diff --git a/src/config/config_collapse.c b/src/config/config_collapse.c
index ea956ebfff9..7fe78d06ba7 100644
--- a/src/config/config_collapse.c
+++ b/src/config/config_collapse.c
@@ -47,7 +47,7 @@ __wt_config_collapse(
 		if (k.type != WT_CONFIG_ITEM_STRING &&
 		    k.type != WT_CONFIG_ITEM_ID)
 			WT_ERR_MSG(session, EINVAL,
-			    "Invalid configuration key found: '%s'\n", k.str);
+			    "Invalid configuration key found: '%s'", k.str);
 		WT_ERR(__wt_config_get(session, cfg, &k, &v));
 		/* Include the quotes around string keys/values. */
 		if (k.type == WT_CONFIG_ITEM_STRING) {
@@ -132,7 +132,7 @@ __config_merge_scan(WT_SESSION_IMPL *session,
 		if (k.type != WT_CONFIG_ITEM_STRING &&
 		    k.type != WT_CONFIG_ITEM_ID)
 			WT_ERR_MSG(session, EINVAL,
-			    "Invalid configuration key found: '%s'\n", k.str);
+			    "Invalid configuration key found: '%s'", k.str);
 
 		/* Include the quotes around string keys/values. */
 		if (k.type == WT_CONFIG_ITEM_STRING) {
diff --git a/src/config/config_def.c b/src/config/config_def.c
index 7bad5f12a9f..7bce4bc9cef 100644
--- a/src/config/config_def.c
+++ b/src/config/config_def.c
@@ -246,6 +246,9 @@ static const WT_CONFIG_CHECK confchk_WT_SESSION_create[] = {
 	{ "format", "string", NULL, "choices=[\"btree\"]", NULL, 0 },
 	{ "huffman_key", "string", NULL, NULL, NULL, 0 },
 	{ "huffman_value", "string", NULL, NULL, NULL, 0 },
+	{ "ignore_in_memory_cache_size", "boolean",
+	    NULL, NULL,
+	    NULL, 0 },
 	{ "immutable", "boolean", NULL, NULL, NULL, 0 },
 	{ "internal_item_max", "int", NULL, "min=0", NULL, 0 },
 	{ "internal_key_max", "int", NULL, "min=0", NULL, 0 },
@@ -413,6 +416,9 @@ static const WT_CONFIG_CHECK confchk_file_config[] = {
 	{ "format", "string", NULL, "choices=[\"btree\"]", NULL, 0 },
 	{ "huffman_key", "string", NULL, NULL, NULL, 0 },
 	{ "huffman_value", "string", NULL, NULL, NULL, 0 },
+	{ "ignore_in_memory_cache_size", "boolean",
+	    NULL, NULL,
+	    NULL, 0 },
 	{ "internal_item_max", "int", NULL, "min=0", NULL, 0 },
 	{ "internal_key_max", "int", NULL, "min=0", NULL, 0 },
 	{ "internal_key_truncate", "boolean", NULL, NULL, NULL, 0 },
@@ -471,6 +477,9 @@ static const WT_CONFIG_CHECK confchk_file_meta[] = {
 	{ "huffman_key", "string", NULL, NULL, NULL, 0 },
 	{ "huffman_value", "string", NULL, NULL, NULL, 0 },
 	{ "id", "string", NULL, NULL, NULL, 0 },
+	{ "ignore_in_memory_cache_size", "boolean",
+	    NULL, NULL,
+	    NULL, 0 },
 	{ "internal_item_max", "int", NULL, "min=0", NULL, 0 },
 	{ "internal_key_max", "int", NULL, "min=0", NULL, 0 },
 	{ "internal_key_truncate", "boolean", NULL, NULL, NULL, 0 },
@@ -544,6 +553,9 @@ static const WT_CONFIG_CHECK confchk_lsm_meta[] = {
 	{ "format", "string", NULL, "choices=[\"btree\"]", NULL, 0 },
 	{ "huffman_key", "string", NULL, NULL, NULL, 0 },
 	{ "huffman_value", "string", NULL, NULL, NULL, 0 },
+	{ "ignore_in_memory_cache_size", "boolean",
+	    NULL, NULL,
+	    NULL, 0 },
 	{ "internal_item_max", "int", NULL, "min=0", NULL, 0 },
 	{ "internal_key_max", "int", NULL, "min=0", NULL, 0 },
 	{ "internal_key_truncate", "boolean", NULL, NULL, NULL, 0 },
@@ -1053,18 +1065,18 @@ static const WT_CONFIG_ENTRY config_entries[] = {
 	  "block_compressor=,cache_resident=false,checksum=uncompressed,"
 	  "colgroups=,collator=,columns=,dictionary=0,encryption=(keyid=,"
 	  "name=),exclusive=false,extractor=,format=btree,huffman_key=,"
-	  "huffman_value=,immutable=false,internal_item_max=0,"
-	  "internal_key_max=0,internal_key_truncate=true,"
-	  "internal_page_max=4KB,key_format=u,key_gap=10,leaf_item_max=0,"
-	  "leaf_key_max=0,leaf_page_max=32KB,leaf_value_max=0,"
-	  "log=(enabled=true),lsm=(auto_throttle=true,bloom=true,"
-	  "bloom_bit_count=16,bloom_config=,bloom_hash_count=8,"
+	  "huffman_value=,ignore_in_memory_cache_size=false,immutable=false"
+	  ",internal_item_max=0,internal_key_max=0,"
+	  "internal_key_truncate=true,internal_page_max=4KB,key_format=u,"
+	  "key_gap=10,leaf_item_max=0,leaf_key_max=0,leaf_page_max=32KB,"
+	  "leaf_value_max=0,log=(enabled=true),lsm=(auto_throttle=true,"
+	  "bloom=true,bloom_bit_count=16,bloom_config=,bloom_hash_count=8,"
 	  "bloom_oldest=false,chunk_count_limit=0,chunk_max=5GB,"
 	  "chunk_size=10MB,merge_max=15,merge_min=0),memory_page_max=5MB,"
 	  "os_cache_dirty_max=0,os_cache_max=0,prefix_compression=false,"
 	  "prefix_compression_min=4,source=,split_deepen_min_child=0,"
 	  "split_deepen_per_child=0,split_pct=75,type=file,value_format=u",
-	  confchk_WT_SESSION_create, 40
+	  confchk_WT_SESSION_create, 41
 	},
 	{ "WT_SESSION.drop",
 	  "checkpoint_wait=true,force=false,lock_wait=true,"
@@ -1148,7 +1160,8 @@ static const WT_CONFIG_ENTRY config_entries[] = {
 	  "allocation_size=4KB,app_metadata=,block_allocation=best,"
 	  "block_compressor=,cache_resident=false,checksum=uncompressed,"
 	  "collator=,columns=,dictionary=0,encryption=(keyid=,name=),"
-	  "format=btree,huffman_key=,huffman_value=,internal_item_max=0,"
+	  "format=btree,huffman_key=,huffman_value=,"
+	  "ignore_in_memory_cache_size=false,internal_item_max=0,"
 	  "internal_key_max=0,internal_key_truncate=true,"
 	  "internal_page_max=4KB,key_format=u,key_gap=10,leaf_item_max=0,"
 	  "leaf_key_max=0,leaf_page_max=32KB,leaf_value_max=0,"
@@ -1156,14 +1169,15 @@ static const WT_CONFIG_ENTRY config_entries[] = {
 	  "os_cache_max=0,prefix_compression=false,prefix_compression_min=4"
 	  ",split_deepen_min_child=0,split_deepen_per_child=0,split_pct=75,"
 	  "value_format=u",
-	  confchk_file_config, 33
+	  confchk_file_config, 34
 	},
 	{ "file.meta",
 	  "allocation_size=4KB,app_metadata=,block_allocation=best,"
 	  "block_compressor=,cache_resident=false,checkpoint=,"
 	  "checkpoint_lsn=,checksum=uncompressed,collator=,columns=,"
 	  "dictionary=0,encryption=(keyid=,name=),format=btree,huffman_key="
-	  ",huffman_value=,id=,internal_item_max=0,internal_key_max=0,"
+	  ",huffman_value=,id=,ignore_in_memory_cache_size=false,"
+	  "internal_item_max=0,internal_key_max=0,"
 	  "internal_key_truncate=true,internal_page_max=4KB,key_format=u,"
 	  "key_gap=10,leaf_item_max=0,leaf_key_max=0,leaf_page_max=32KB,"
 	  "leaf_value_max=0,log=(enabled=true),memory_page_max=5MB,"
@@ -1171,7 +1185,7 @@ static const WT_CONFIG_ENTRY config_entries[] = {
 	  "prefix_compression_min=4,split_deepen_min_child=0,"
 	  "split_deepen_per_child=0,split_pct=75,value_format=u,"
 	  "version=(major=0,minor=0)",
-	  confchk_file_meta, 37
+	  confchk_file_meta, 38
 	},
 	{ "index.meta",
 	  "app_metadata=,collator=,columns=,extractor=,immutable=false,"
@@ -1183,18 +1197,19 @@ static const WT_CONFIG_ENTRY config_entries[] = {
 	  "block_compressor=,cache_resident=false,checksum=uncompressed,"
 	  "chunks=,collator=,columns=,dictionary=0,encryption=(keyid=,"
 	  "name=),format=btree,huffman_key=,huffman_value=,"
-	  "internal_item_max=0,internal_key_max=0,"
-	  "internal_key_truncate=true,internal_page_max=4KB,key_format=u,"
-	  "key_gap=10,last=,leaf_item_max=0,leaf_key_max=0,"
-	  "leaf_page_max=32KB,leaf_value_max=0,log=(enabled=true),"
-	  "lsm=(auto_throttle=true,bloom=true,bloom_bit_count=16,"
-	  "bloom_config=,bloom_hash_count=8,bloom_oldest=false,"
-	  "chunk_count_limit=0,chunk_max=5GB,chunk_size=10MB,merge_max=15,"
-	  "merge_min=0),memory_page_max=5MB,old_chunks=,"
-	  "os_cache_dirty_max=0,os_cache_max=0,prefix_compression=false,"
-	  "prefix_compression_min=4,split_deepen_min_child=0,"
-	  "split_deepen_per_child=0,split_pct=75,value_format=u",
-	  confchk_lsm_meta, 37
+	  "ignore_in_memory_cache_size=false,internal_item_max=0,"
+	  "internal_key_max=0,internal_key_truncate=true,"
+	  "internal_page_max=4KB,key_format=u,key_gap=10,last=,"
+	  "leaf_item_max=0,leaf_key_max=0,leaf_page_max=32KB,"
+	  "leaf_value_max=0,log=(enabled=true),lsm=(auto_throttle=true,"
+	  "bloom=true,bloom_bit_count=16,bloom_config=,bloom_hash_count=8,"
+	  "bloom_oldest=false,chunk_count_limit=0,chunk_max=5GB,"
+	  "chunk_size=10MB,merge_max=15,merge_min=0),memory_page_max=5MB,"
+	  "old_chunks=,os_cache_dirty_max=0,os_cache_max=0,"
+	  "prefix_compression=false,prefix_compression_min=4,"
+	  "split_deepen_min_child=0,split_deepen_per_child=0,split_pct=75,"
+	  "value_format=u",
+	  confchk_lsm_meta, 38
 	},
 	{ "table.meta",
 	  "app_metadata=,colgroups=,collator=,columns=,key_format=u,"
diff --git a/src/conn/conn_cache.c b/src/conn/conn_cache.c
index 6788b1f7f47..1b8b3183d3c 100644
--- a/src/conn/conn_cache.c
+++ b/src/conn/conn_cache.c
@@ -42,47 +42,38 @@ __cache_config_local(WT_SESSION_IMPL *session, bool shared, const char *cfg[])
 	WT_RET(__wt_config_gets(session, cfg, "eviction_trigger", &cval));
 	cache->eviction_trigger = (u_int)cval.val;
 
-	if (F_ISSET(conn, WT_CONN_IN_MEMORY))
-		cache->eviction_checkpoint_target =
-		    cache->eviction_dirty_target =
-		    cache->eviction_dirty_trigger = 100U;
-	else {
-		WT_RET(__wt_config_gets(
-		    session, cfg, "eviction_checkpoint_target", &cval));
-		cache->eviction_checkpoint_target = (u_int)cval.val;
+	WT_RET(__wt_config_gets(
+	    session, cfg, "eviction_checkpoint_target", &cval));
+	cache->eviction_checkpoint_target = (u_int)cval.val;
 
-		WT_RET(__wt_config_gets(
-		    session, cfg, "eviction_dirty_target", &cval));
-		cache->eviction_dirty_target = (u_int)cval.val;
+	WT_RET(__wt_config_gets(session, cfg, "eviction_dirty_target", &cval));
+	cache->eviction_dirty_target = (u_int)cval.val;
 
-		/*
-		 * Don't allow the dirty target to be larger than the overall
-		 * target.
-		 */
-		if (cache->eviction_dirty_target > cache->eviction_target)
-			cache->eviction_dirty_target = cache->eviction_target;
+	/*
+	 * Don't allow the dirty target to be larger than the overall
+	 * target.
+	 */
+	if (cache->eviction_dirty_target > cache->eviction_target)
+		cache->eviction_dirty_target = cache->eviction_target;
 
-		/*
-		 * Sanity check the checkpoint target: don't allow a value
-		 * lower than the dirty target.
-		 */
-		if (cache->eviction_checkpoint_target > 0 &&
-		    cache->eviction_checkpoint_target <
-		    cache->eviction_dirty_target)
-			cache->eviction_checkpoint_target =
-			    cache->eviction_dirty_target;
+	/*
+	 * Sanity check the checkpoint target: don't allow a value
+	 * lower than the dirty target.
+	 */
+	if (cache->eviction_checkpoint_target > 0 &&
+	    cache->eviction_checkpoint_target < cache->eviction_dirty_target)
+		cache->eviction_checkpoint_target =
+		    cache->eviction_dirty_target;
 
-		WT_RET(__wt_config_gets(
-		    session, cfg, "eviction_dirty_trigger", &cval));
-		cache->eviction_dirty_trigger = (u_int)cval.val;
+	WT_RET(__wt_config_gets(session, cfg, "eviction_dirty_trigger", &cval));
+	cache->eviction_dirty_trigger = (u_int)cval.val;
 
-		/*
-		 * Don't allow the dirty trigger to be larger than the overall
-		 * trigger or we can get stuck with a cache full of dirty data.
-		 */
-		if (cache->eviction_dirty_trigger > cache->eviction_trigger)
-			cache->eviction_dirty_trigger = cache->eviction_trigger;
-	}
+	/*
+	 * Don't allow the dirty trigger to be larger than the overall
+	 * trigger or we can get stuck with a cache full of dirty data.
+	 */
+	if (cache->eviction_dirty_trigger > cache->eviction_trigger)
+		cache->eviction_dirty_trigger = cache->eviction_trigger;
 
 	WT_RET(__wt_config_gets(session, cfg, "eviction.threads_max", &cval));
 	WT_ASSERT(session, cval.val > 0);
diff --git a/src/conn/conn_ckpt.c b/src/conn/conn_ckpt.c
index b4913043d63..faeef4e71a2 100644
--- a/src/conn/conn_ckpt.c
+++ b/src/conn/conn_ckpt.c
@@ -87,22 +87,36 @@ __ckpt_server(void *arg)
 		 */
 		__wt_cond_wait(session, conn->ckpt_cond, conn->ckpt_usecs);
 
-		/* Checkpoint the database. */
-		WT_ERR(wt_session->checkpoint(wt_session, NULL));
-
-		/* Reset. */
-		if (conn->ckpt_logsize) {
-			__wt_log_written_reset(session);
-			conn->ckpt_signalled = false;
-
-			/*
-			 * In case we crossed the log limit during the
-			 * checkpoint and the condition variable was already
-			 * signalled, do a tiny wait to clear it so we don't do
-			 * another checkpoint immediately.
-			 */
-			__wt_cond_wait(session, conn->ckpt_cond, 1);
-		}
+		/*
+		 * Checkpoint the database if the connection is marked dirty.
+		 * A connection is marked dirty whenever a btree gets marked
+		 * dirty, which reflects upon a change in the database that
+		 * needs to be checkpointed. Said that, there can be short
+		 * instances when a btree gets marked dirty and the connection
+		 * is yet to be. We might skip a checkpoint in that short
+		 * instance, which is okay because by the next time we get to
+		 * checkpoint, the connection would have been marked dirty and
+		 * hence the checkpoint will not be skipped this time.
+		 */
+		if (conn->modified) {
+			WT_ERR(wt_session->checkpoint(wt_session, NULL));
+
+			/* Reset. */
+			if (conn->ckpt_logsize) {
+				__wt_log_written_reset(session);
+				conn->ckpt_signalled = false;
+
+				/*
+				 * In case we crossed the log limit during the
+				 * checkpoint and the condition variable was
+				 * already signalled, do a tiny wait to clear
+				 * it so we don't do another checkpoint
+				 * immediately.
+				 */
+				__wt_cond_wait(session, conn->ckpt_cond, 1);
+			}
+		} else
+			WT_STAT_CONN_INCR(session, txn_checkpoint_skipped);
 	}
 
 	if (0) {
diff --git a/src/conn/conn_log.c b/src/conn/conn_log.c
index 2786526c2fa..34743034877 100644
--- a/src/conn/conn_log.c
+++ b/src/conn/conn_log.c
@@ -839,10 +839,10 @@ __log_server(void *arg)
 
 		/* Wait until the next event. */
 
-		WT_ERR(__wt_epoch(session, &start));
+		__wt_epoch(session, &start);
 		__wt_cond_auto_wait_signal(session,
 		    conn->log_cond, did_work, &signalled);
-		WT_ERR(__wt_epoch(session, &now));
+		__wt_epoch(session, &now);
 		timediff = WT_TIMEDIFF_MS(now, start);
 	}
 
diff --git a/src/conn/conn_stat.c b/src/conn/conn_stat.c
index 66979dfd023..d5a31c671c0 100644
--- a/src/conn/conn_stat.c
+++ b/src/conn/conn_stat.c
@@ -415,7 +415,7 @@ __statlog_log_one(WT_SESSION_IMPL *session, WT_ITEM *path, WT_ITEM *tmp)
 	conn = S2C(session);
 
 	/* Get the current local time of day. */
-	WT_RET(__wt_epoch(session, &ts));
+	__wt_epoch(session, &ts);
 	tm = localtime_r(&ts.tv_sec, &_tm);
 
 	/* Create the logging path name for this time of day. */
diff --git a/src/conn/conn_sweep.c b/src/conn/conn_sweep.c
index 03593f8951a..dba37fa2eb0 100644
--- a/src/conn/conn_sweep.c
+++ b/src/conn/conn_sweep.c
@@ -271,7 +271,7 @@ __sweep_server(void *arg)
 		/* Wait until the next event. */
 		__wt_cond_wait(session,
 		    conn->sweep_cond, conn->sweep_interval * WT_MILLION);
-		WT_ERR(__wt_seconds(session, &now));
+		__wt_seconds(session, &now);
 
 		WT_STAT_CONN_INCR(session, dh_sweeps);
 
diff --git a/src/docs/wtperf.dox b/src/docs/wtperf.dox
index a49d0d9f871..df66ad43355 100644
--- a/src/docs/wtperf.dox
+++ b/src/docs/wtperf.dox
@@ -150,33 +150,25 @@ number of async worker threads
 @par checkpoint_interval (unsigned int, default=120)
 checkpoint every interval seconds during the workload phase.
 @par checkpoint_stress_rate (unsigned int, default=0)
-checkpoint every rate operations during the populate phase in the
-populate thread(s), 0 to disable
+checkpoint every rate operations during the populate phase in the  populate thread(s), 0 to disable
 @par checkpoint_threads (unsigned int, default=0)
 number of checkpoint threads
-@par conn_config (string, default=create)
+@par conn_config (string, default="create")
 connection configuration string
 @par compact (boolean, default=false)
 post-populate compact for LSM merging activity
-@par compression (string, default=none)
-compression extension.  Allowed configuration values are: 'none',
-'lz4', 'snappy', 'zlib'
+@par compression (string, default="none")
+compression extension.  Allowed configuration values are:  'none', 'lz4', 'snappy', 'zlib'
 @par create (boolean, default=true)
 do population phase; false to use existing database
 @par database_count (unsigned int, default=1)
-number of WiredTiger databases to use. Each database will execute the
-workload using a separate home directory and complete set of worker
-threads
-@par drop_tables (unsigned int, default=0)
-Whether to drop all tables at the end of the run, and report time
-taken to do the drop.
+number of WiredTiger databases to use. Each database will execute the  workload using a separate home directory and complete set of worker  threads
+@par drop_tables (boolean, default=false)
+Whether to drop all tables at the end of the run, and report time taken  to do the drop.
 @par icount (unsigned int, default=5000)
-number of records to initially populate. If multiple tables are
-configured the count is spread evenly across all tables.
+number of records to initially populate. If multiple tables are  configured the count is spread evenly across all tables.
 @par idle_table_cycle (unsigned int, default=0)
-Enable regular create and drop of idle tables, value is the maximum
-number of seconds a create or drop is allowed before flagging an
-error. Default 0 which means disabled.
+Enable regular create and drop of idle tables, value is the maximum  number of seconds a create or drop is allowed before flagging an error.  Default 0 which means disabled.
 @par index (boolean, default=false)
 Whether to create an index on the value field.
 @par insert_rmw (boolean, default=false)
@@ -188,28 +180,21 @@ perform partial logging on first table only.
 @par log_like_table (boolean, default=false)
 Append all modification operations to another shared table.
 @par min_throughput (unsigned int, default=0)
-notify if any throughput measured is less than this amount. Aborts or
-prints warning based on min_throughput_fatal setting. Requires
-sample_interval to be configured
+notify if any throughput measured is less than this amount.  Aborts or prints warning based on min_throughput_fatal setting.  Requires sample_interval to be configured
 @par min_throughput_fatal (boolean, default=false)
 print warning (false) or abort (true) of min_throughput failure.
 @par max_latency (unsigned int, default=0)
-notify if any latency measured exceeds this number of
-milliseconds.Aborts or prints warning based on min_throughput_fatal
-setting. Requires sample_interval to be configured
+notify if any latency measured exceeds this number of milliseconds. Aborts or prints warning based on min_throughput_fatal setting.  Requires sample_interval to be configured
 @par max_latency_fatal (boolean, default=false)
 print warning (false) or abort (true) of max_latency failure.
 @par pareto (unsigned int, default=0)
-use pareto distribution for random numbers. Zero to disable, otherwise
-a percentage indicating how aggressive the distribution should be.
+use pareto distribution for random numbers. Zero  to disable, otherwise a percentage indicating how aggressive the  distribution should be.
 @par populate_ops_per_txn (unsigned int, default=0)
-number of operations to group into each transaction in the populate
-phase, zero for auto-commit
+number of operations to group into each transaction in the populate  phase, zero for auto-commit
 @par populate_threads (unsigned int, default=1)
 number of populate threads, 1 for bulk load
 @par random_range (unsigned int, default=0)
-if non zero choose a value from within this range as the key for
-insert operations
+if non zero choose a value from within this range as the key for  insert operations
 @par random_value (boolean, default=false)
 generate random content for the value
 @par range_partition (boolean, default=false)
@@ -217,9 +202,7 @@ partition data by range (vs hash)
 @par read_range (unsigned int, default=0)
 scan a range of keys after each search
 @par readonly (boolean, default=false)
-reopen the connection between populate and workload phases in readonly
-mode.  Requires reopen_connection turned on (default).  Requires that
-read be the only workload specified
+reopen the connection between populate and workload phases in readonly  mode.  Requires reopen_connection turned on (default).  Requires that  read be the only workload specified
 @par reopen_connection (boolean, default=true)
 close and reopen the connection between populate and workload phases
 @par report_interval (unsigned int, default=2)
@@ -231,40 +214,22 @@ total workload seconds
 @par sample_interval (unsigned int, default=0)
 performance logging every interval seconds, 0 to disable
 @par sample_rate (unsigned int, default=50)
-how often the latency of operations is measured. One for every
-operation,two for every second operation, three for every third
-operation etc.
-@par sess_config (string, default=)
+how often the latency of operations is measured. One for every operation, two for every second operation, three for every third operation etc.
+@par sess_config (string, default="")
 session configuration string
 @par session_count_idle (unsigned int, default=0)
 number of idle sessions to create. Default 0.
-@par table_config (string, default=key_format=S,value_format=S,type=lsm,exclusive=true,allocation_size=4kb,internal_page_max=64kb,leaf_page_max=4kb,split_pct=100)
+@par table_config (string, default="key_format=S,value_format=S,type=lsm,exclusive=true, allocation_size=4kb,internal_page_max=64kb,leaf_page_max=4kb, split_pct=100")
 table configuration string
 @par table_count (unsigned int, default=1)
-number of tables to run operations over. Keys are divided evenly over
-the tables. Cursors are held open on all tables. Default 1, maximum
-99999.
+number of tables to run operations over. Keys are divided evenly  over the tables. Cursors are held open on all tables. Default 1, maximum  99999.
 @par table_count_idle (unsigned int, default=0)
 number of tables to create, that won't be populated. Default 0.
-@par threads (string, default=)
-workload configuration: each 'count' entry is the total number of
-threads, and the 'insert', 'read' and 'update' entries are the ratios
-of insert, read and update operations done by each worker thread; If a
-throttle value is provided each thread will do a maximum of that
-number of operations per second; multiple workload configurations may
-be specified per threads configuration; for example, a more complex
-threads configuration might be
-'threads=((count=2,reads=1)(count=8,reads=1,inserts=2,updates=1))'
-which would create 2 threads doing nothing but reads and 8 threads
-each doing 50% inserts and 25% reads and updates.  Allowed
-configuration values are 'count', 'throttle', 'update_delta', 'reads',
-'inserts', 'updates', 'truncate', 'truncate_pct' and 'truncate_count'.
-There are also behavior modifiers, supported modifiers are
-'ops_per_txn'
-@par transaction_config (string, default=)
-transaction configuration string, relevant when populate_opts_per_txn
-is nonzero
-@par table_name (string, default=test)
+@par threads (string, default="")
+workload configuration: each 'count'  entry is the total number of threads, and the 'insert', 'read' and  'update' entries are the ratios of insert, read and update operations  done by each worker thread; If a throttle value is provided each thread  will do a maximum of that number of operations per second; multiple  workload configurations may be specified per threads configuration;  for example, a more complex threads configuration might be  'threads=((count=2,reads=1)(count=8,reads=1,inserts=2,updates=1))'  which would create 2 threads doing nothing but reads and 8 threads  each doing 50% inserts and 25% reads and updates.  Allowed configuration  values are 'count', 'throttle', 'update_delta', 'reads', 'inserts',  'updates', 'truncate', 'truncate_pct' and 'truncate_count'. There are  also behavior modifiers, supported modifiers are 'ops_per_txn'
+@par transaction_config (string, default="")
+WT_SESSION.begin_transaction configuration string, applied during the  populate phase when populate_ops_per_txn is nonzero
+@par table_name (string, default="test")
 table name
 @par truncate_single_ops (boolean, default=false)
 Implement truncate via cursor remove instead of session API
diff --git a/src/evict/evict_lru.c b/src/evict/evict_lru.c
index acc81f566a5..45ec9bce3b5 100644
--- a/src/evict/evict_lru.c
+++ b/src/evict/evict_lru.c
@@ -233,10 +233,10 @@ __wt_evict_thread_run(WT_SESSION_IMPL *session, WT_THREAD *thread)
 
 #ifdef HAVE_DIAGNOSTIC
 	/*
-	 * Ensure the cache stuck timer is initialized when starting eviction
+	 * Ensure the cache stuck timer is initialized when starting eviction.
 	 */
 	if (thread->id == 0)
-		WT_ERR(__wt_epoch(session, &cache->stuck_ts));
+		__wt_epoch(session, &cache->stuck_ts);
 #endif
 
 	while (F_ISSET(conn, WT_CONN_EVICTION_RUN) &&
@@ -350,10 +350,10 @@ __evict_server(WT_SESSION_IMPL *session, bool *did_work)
 	} else if (cache->pages_evicted != cache->pages_evict) {
 		cache->pages_evicted = cache->pages_evict;
 #ifdef HAVE_DIAGNOSTIC
-		WT_RET(__wt_epoch(session, &cache->stuck_ts));
+		__wt_epoch(session, &cache->stuck_ts);
 	} else {
 		/* After being stuck for 5 minutes, give up. */
-		WT_RET(__wt_epoch(session, &now));
+		__wt_epoch(session, &now);
 		if (WT_TIMEDIFF_SEC(now, cache->stuck_ts) > 300) {
 			ret = ETIMEDOUT;
 			__wt_err(session, ret,
@@ -465,16 +465,16 @@ __evict_update_work(WT_SESSION_IMPL *session)
 	 */
 	bytes_max = conn->cache_size + 1;
 	bytes_inuse = __wt_cache_bytes_inuse(cache);
-	if (bytes_inuse > (cache->eviction_target * bytes_max) / 100)
-		F_SET(cache, WT_CACHE_EVICT_CLEAN);
 	if (__wt_eviction_clean_needed(session, NULL))
 		F_SET(cache, WT_CACHE_EVICT_CLEAN | WT_CACHE_EVICT_CLEAN_HARD);
+	else if (bytes_inuse > (cache->eviction_target * bytes_max) / 100)
+		F_SET(cache, WT_CACHE_EVICT_CLEAN);
 
 	dirty_inuse = __wt_cache_dirty_leaf_inuse(cache);
-	if (dirty_inuse > (cache->eviction_dirty_target * bytes_max) / 100)
-		F_SET(cache, WT_CACHE_EVICT_DIRTY);
 	if (__wt_eviction_dirty_needed(session, NULL))
 		F_SET(cache, WT_CACHE_EVICT_DIRTY | WT_CACHE_EVICT_DIRTY_HARD);
+	else if (dirty_inuse > (cache->eviction_dirty_target * bytes_max) / 100)
+		F_SET(cache, WT_CACHE_EVICT_DIRTY);
 
 	/*
 	 * If application threads are blocked by the total volume of data in
@@ -506,12 +506,6 @@ __evict_update_work(WT_SESSION_IMPL *session)
 		F_CLR(cache, WT_CACHE_EVICT_CLEAN | WT_CACHE_EVICT_CLEAN_HARD);
 	}
 
-	/* If threads are blocked by eviction we should be looking for pages. */
-	WT_ASSERT(session, !F_ISSET(cache, WT_CACHE_EVICT_CLEAN_HARD) ||
-	    F_ISSET(cache, WT_CACHE_EVICT_CLEAN));
-	WT_ASSERT(session, !F_ISSET(cache, WT_CACHE_EVICT_DIRTY_HARD) ||
-	    F_ISSET(cache, WT_CACHE_EVICT_DIRTY));
-
 	WT_STAT_CONN_SET(session, cache_eviction_state,
 	    F_MASK(cache, WT_CACHE_EVICT_MASK));
 
@@ -543,7 +537,7 @@ __evict_pass(WT_SESSION_IMPL *session)
 
 	/* Evict pages from the cache. */
 	for (loop = 0; cache->pass_intr == 0; loop++) {
-		WT_RET(__wt_epoch(session, &now));
+		__wt_epoch(session, &now);
 		if (loop == 0)
 			prev = now;
 
@@ -895,12 +889,11 @@ __evict_lru_walk(WT_SESSION_IMPL *session)
 	/* Fill the next queue (that isn't the urgent queue). */
 	queue = cache->evict_fill_queue;
 	other_queue = cache->evict_queues + (1 - (queue - cache->evict_queues));
+	cache->evict_fill_queue = other_queue;
 
 	/* If this queue is full, try the other one. */
 	if (__evict_queue_full(queue) && !__evict_queue_full(other_queue))
 		queue = other_queue;
-	cache->evict_fill_queue =
-	    &cache->evict_queues[1 - (queue - cache->evict_queues)];
 
 	/*
 	 * If both queues are full and haven't been empty on recent refills,
@@ -1079,6 +1072,17 @@ __evict_walk(WT_SESSION_IMPL *session, WT_EVICT_QUEUE *queue)
 	start_slot = slot = queue->evict_entries;
 	max_entries = WT_MIN(slot + WT_EVICT_WALK_INCR, cache->evict_slots);
 
+	/*
+	 * Another pathological case: if there are only a tiny number of
+	 * candidate pages in cache, don't put all of them on one queue.
+	 */
+	if (F_ISSET(cache, WT_CACHE_EVICT_CLEAN))
+		max_entries = WT_MIN(max_entries,
+		    1 + (uint32_t)(__wt_cache_pages_inuse(cache) / 2));
+	else
+		max_entries = WT_MIN(max_entries,
+		    1 + (uint32_t)(cache->pages_dirty_leaf / 2));
+
 retry:	while (slot < max_entries) {
 		/*
 		 * If another thread is waiting on the eviction server to clear
@@ -1508,19 +1512,22 @@ fast:		/* If the page can't be evicted, give up. */
 		btree->evict_walk_period = 0;
 
 	/*
-	 * If we happen to end up on the root page, clear it.  We have to track
-	 * hazard pointers, and the root page complicates that calculation.
+	 * If we happen to end up on the root page or a page requiring urgent
+	 * eviction, clear it.  We have to track hazard pointers, and the root
+	 * page complicates that calculation.
 	 *
 	 * Likewise if we found no new candidates during the walk: there is no
-	 * point keeping a page pinned, since it may be the only candidate in an
-	 * idle tree.
+	 * point keeping a page pinned, since it may be the only candidate in
+	 * an idle tree.
 	 *
 	 * If we land on a page requiring forced eviction, move on to the next
 	 * page: we want this page evicted as quickly as possible.
 	 */
 	if ((ref = btree->evict_ref) != NULL) {
 		/* Give up the walk occasionally. */
-		if (__wt_ref_is_root(ref) || evict == start || give_up)
+		if (__wt_ref_is_root(ref) || evict == start || give_up ||
+		    ref->page->read_gen == WT_READGEN_OLDEST ||
+		    ref->page->memory_footprint >= btree->splitmempage)
 			WT_RET(__evict_clear_walk(session, restarts == 0));
 		else if (ref->page->read_gen == WT_READGEN_OLDEST)
 			WT_RET_NOTFOUND_OK(__wt_tree_walk_count(
@@ -1543,14 +1550,14 @@ __evict_get_ref(
     WT_SESSION_IMPL *session, bool is_server, WT_BTREE **btreep, WT_REF **refp)
 {
 	WT_CACHE *cache;
-	WT_DECL_RET;
 	WT_EVICT_ENTRY *evict;
 	WT_EVICT_QUEUE *queue, *other_queue, *urgent_queue;
 	uint32_t candidates;
-	bool is_app, urgent_ok;
+	bool is_app, server_only, urgent_ok;
 
 	cache = S2C(session)->cache;
 	is_app = !F_ISSET(session, WT_SESSION_INTERNAL);
+	server_only = is_server && !WT_EVICT_HAS_WORKERS(session);
 	urgent_ok = (!is_app && !is_server) ||
 	    !WT_EVICT_HAS_WORKERS(session) ||
 	    __wt_cache_aggressive(session);
@@ -1569,7 +1576,8 @@ __evict_get_ref(
 	}
 
 	/*
-	 * The server repopulates whenever the other queue is not full.
+	 * The server repopulates whenever the other queue is not full, as long
+	 * as at least one page has been evicted out of the current queue.
 	 *
 	 * Note that there are pathological cases where there are only enough
 	 * eviction candidates in the cache to fill one queue.  In that case,
@@ -1577,18 +1585,14 @@ __evict_get_ref(
 	 * Such cases are extremely rare in real applications.
 	 */
 	if (is_server &&
+	    (!urgent_ok || __evict_queue_empty(urgent_queue, false)) &&
+	    !__evict_queue_full(cache->evict_current_queue) &&
+	    !__evict_queue_full(cache->evict_fill_queue) &&
 	    (cache->evict_empty_score > WT_EVICT_SCORE_CUTOFF ||
-	    __evict_queue_empty(cache->evict_fill_queue, false))) {
-		while ((ret = __wt_spin_trylock(
-		    session, &cache->evict_queue_lock)) == EBUSY)
-			if ((!urgent_ok ||
-			    __evict_queue_empty(urgent_queue, false)) &&
-			    !__evict_queue_full(cache->evict_fill_queue))
-				return (WT_NOTFOUND);
+	    __evict_queue_empty(cache->evict_fill_queue, false)))
+		return (WT_NOTFOUND);
 
-		WT_RET(ret);
-	} else
-		__wt_spin_lock(session, &cache->evict_queue_lock);
+	__wt_spin_lock(session, &cache->evict_queue_lock);
 
 	/* Check the urgent queue first. */
 	if (urgent_ok && !__evict_queue_empty(urgent_queue, false))
@@ -1596,17 +1600,15 @@ __evict_get_ref(
 	else {
 		/*
 		 * Check if the current queue needs to change.
-		 * The current queue could have changed while we waited for
-		 * the lock.
 		 *
 		 * The server will only evict half of the pages before looking
-		 * for more. The remainder are left to eviction workers (if any
-		 * configured), or application threads if necessary.
+		 * for more, but should only switch queues if there are no
+		 * other eviction workers.
 		 */
 		queue = cache->evict_current_queue;
 		other_queue = cache->evict_other_queue;
-		if (__evict_queue_empty(queue, is_server) &&
-		    !__evict_queue_empty(other_queue, is_server)) {
+		if (__evict_queue_empty(queue, server_only) &&
+		    !__evict_queue_empty(other_queue, server_only)) {
 			cache->evict_current_queue = other_queue;
 			cache->evict_other_queue = queue;
 		}
@@ -1715,15 +1717,19 @@ __evict_get_ref(
 static int
 __evict_page(WT_SESSION_IMPL *session, bool is_server)
 {
+	struct timespec enter, leave;
 	WT_BTREE *btree;
 	WT_CACHE *cache;
 	WT_DECL_RET;
 	WT_REF *ref;
+	bool app_timer;
 
 	WT_RET(__evict_get_ref(session, is_server, &btree, &ref));
 	WT_ASSERT(session, ref->state == WT_REF_LOCKED);
 
+	app_timer = false;
 	cache = S2C(session)->cache;
+
 	/*
 	 * An internal session flags either the server itself or an eviction
 	 * worker thread.
@@ -1739,6 +1745,10 @@ __evict_page(WT_SESSION_IMPL *session, bool is_server)
 			WT_STAT_CONN_INCR(session, cache_eviction_app_dirty);
 		WT_STAT_CONN_INCR(session, cache_eviction_app);
 		cache->app_evicts++;
+		if (WT_STAT_ENABLED(session)) {
+			app_timer = true;
+			__wt_epoch(session, &enter);
+		}
 	}
 
 	/*
@@ -1756,6 +1766,11 @@ __evict_page(WT_SESSION_IMPL *session, bool is_server)
 
 	(void)__wt_atomic_subv32(&btree->evict_busy, 1);
 
+	if (app_timer) {
+		__wt_epoch(session, &leave);
+		WT_STAT_CONN_INCRV(session,
+		    application_evict_time, WT_TIMEDIFF_US(leave, enter));
+	}
 	return (ret);
 }
 
@@ -1767,6 +1782,7 @@ __evict_page(WT_SESSION_IMPL *session, bool is_server)
 int
 __wt_cache_eviction_worker(WT_SESSION_IMPL *session, bool busy, u_int pct_full)
 {
+	struct timespec enter, leave;
 	WT_CACHE *cache;
 	WT_CONNECTION_IMPL *conn;
 	WT_DECL_RET;
@@ -1792,9 +1808,11 @@ __wt_cache_eviction_worker(WT_SESSION_IMPL *session, bool busy, u_int pct_full)
 	/* Wake the eviction server if we need to do work. */
 	__wt_evict_server_wake(session);
 
-	init_evict_count = cache->pages_evict;
+	/* Track how long application threads spend doing eviction. */
+	if (WT_STAT_ENABLED(session) && !F_ISSET(session, WT_SESSION_INTERNAL))
+		__wt_epoch(session, &enter);
 
-	for (;;) {
+	for (init_evict_count = cache->pages_evict;; ret = 0) {
 		/*
 		 * A pathological case: if we're the oldest transaction in the
 		 * system and the eviction server is stuck trying to find space,
@@ -1804,7 +1822,7 @@ __wt_cache_eviction_worker(WT_SESSION_IMPL *session, bool busy, u_int pct_full)
 		if (__wt_cache_stuck(session) && __wt_txn_am_oldest(session)) {
 			--cache->evict_aggressive_score;
 			WT_STAT_CONN_INCR(session, txn_fail_cache);
-			return (WT_ROLLBACK);
+			WT_ERR(WT_ROLLBACK);
 		}
 
 		/*
@@ -1816,7 +1834,7 @@ __wt_cache_eviction_worker(WT_SESSION_IMPL *session, bool busy, u_int pct_full)
 		 * limit the work to 5 evictions and return. If that's not the
 		 * case, we can do more.
 		 */
-		if (!busy && txn_state->snap_min != WT_TXN_NONE &&
+		if (!busy && txn_state->pinned_id != WT_TXN_NONE &&
 		    txn_global->current != txn_global->oldest_id)
 			busy = true;
 		max_pages_evicted = busy ? 5 : 20;
@@ -1825,7 +1843,7 @@ __wt_cache_eviction_worker(WT_SESSION_IMPL *session, bool busy, u_int pct_full)
 		if (!__wt_eviction_needed(session, busy, &pct_full) ||
 		    (pct_full < 100 &&
 		    cache->pages_evict > init_evict_count + max_pages_evicted))
-			return (0);
+			break;
 
 		/*
 		 * Don't make application threads participate in scrubbing for
@@ -1842,7 +1860,7 @@ __wt_cache_eviction_worker(WT_SESSION_IMPL *session, bool busy, u_int pct_full)
 		switch (ret = __evict_page(session, false)) {
 		case 0:
 			if (busy)
-				return (0);
+				goto err;
 			/* FALLTHROUGH */
 		case EBUSY:
 			break;
@@ -1853,9 +1871,18 @@ __wt_cache_eviction_worker(WT_SESSION_IMPL *session, bool busy, u_int pct_full)
 			cache->app_waits++;
 			break;
 		default:
-			return (ret);
+			goto err;
 		}
 	}
+
+err:	if (WT_STAT_ENABLED(session) &&
+	    !F_ISSET(session, WT_SESSION_INTERNAL)) {
+		__wt_epoch(session, &leave);
+		WT_STAT_CONN_INCRV(session,
+		    application_cache_time, WT_TIMEDIFF_US(leave, enter));
+	}
+
+	return (ret);
 	/* NOTREACHED */
 }
 
diff --git a/src/include/api.h b/src/include/api.h
index e1b2f8edaf3..2783d17f825 100644
--- a/src/include/api.h
+++ b/src/include/api.h
@@ -139,7 +139,9 @@
 	(s) = (WT_SESSION_IMPL *)(cur)->session;			\
 	TXN_API_CALL_NOCONF(s, WT_CURSOR, n, cur,			\
 	    ((bt) == NULL) ? NULL : ((WT_BTREE *)(bt))->dhandle);	\
-	if (F_ISSET(S2C(s), WT_CONN_IN_MEMORY) && __wt_cache_full(s))	\
+	if (F_ISSET(S2C(s), WT_CONN_IN_MEMORY) &&			\
+	    !F_ISSET((WT_BTREE *)(bt), WT_BTREE_IGNORE_CACHE) &&	\
+	    __wt_cache_full(s))						\
 		WT_ERR(WT_CACHE_FULL);
 
 #define	JOINABLE_CURSOR_UPDATE_API_CALL(cur, s, n, bt)			\
diff --git a/src/include/btree.h b/src/include/btree.h
index cfaf59e70e1..713d46ae85f 100644
--- a/src/include/btree.h
+++ b/src/include/btree.h
@@ -119,7 +119,7 @@ struct __wt_btree {
 	uint64_t last_recno;		/* Column-store last record number */
 
 	WT_REF root;			/* Root page reference */
-	int modified;			/* If the tree ever modified */
+	bool modified;			/* If the tree ever modified */
 	bool bulk_load_ok;		/* Bulk-load is a possibility */
 
 	WT_BM	*bm;			/* Block manager reference */
@@ -154,18 +154,19 @@ struct __wt_btree {
 	WT_SPINLOCK	flush_lock;	/* Lock to flush the tree's pages */
 
 	/* Flags values up to 0xff are reserved for WT_DHANDLE_* */
-#define	WT_BTREE_BULK		0x00100	/* Bulk-load handle */
-#define	WT_BTREE_IN_MEMORY	0x00200	/* Cache-resident object */
-#define	WT_BTREE_LOOKASIDE	0x00400	/* Look-aside table */
-#define	WT_BTREE_NO_CHECKPOINT	0x00800	/* Disable checkpoints */
-#define	WT_BTREE_NO_EVICTION	0x01000	/* Disable eviction */
-#define	WT_BTREE_NO_LOGGING	0x02000	/* Disable logging */
-#define	WT_BTREE_NO_RECONCILE	0x04000 /* Allow splits, even with no evict */
-#define	WT_BTREE_REBALANCE	0x08000	/* Handle is for rebalance */
-#define	WT_BTREE_SALVAGE	0x10000	/* Handle is for salvage */
-#define	WT_BTREE_SKIP_CKPT	0x20000	/* Handle skipped checkpoint */
-#define	WT_BTREE_UPGRADE	0x40000	/* Handle is for upgrade */
-#define	WT_BTREE_VERIFY		0x80000	/* Handle is for verify */
+#define	WT_BTREE_BULK		0x000100 /* Bulk-load handle */
+#define	WT_BTREE_IGNORE_CACHE	0x000200 /* Cache-resident object */
+#define	WT_BTREE_IN_MEMORY	0x000400 /* Cache-resident object */
+#define	WT_BTREE_LOOKASIDE	0x000800 /* Look-aside table */
+#define	WT_BTREE_NO_CHECKPOINT	0x001000 /* Disable checkpoints */
+#define	WT_BTREE_NO_EVICTION	0x002000 /* Disable eviction */
+#define	WT_BTREE_NO_LOGGING	0x004000 /* Disable logging */
+#define	WT_BTREE_NO_RECONCILE	0x008000 /* Allow splits, even with no evict */
+#define	WT_BTREE_REBALANCE	0x010000 /* Handle is for rebalance */
+#define	WT_BTREE_SALVAGE	0x020000 /* Handle is for salvage */
+#define	WT_BTREE_SKIP_CKPT	0x040000 /* Handle skipped checkpoint */
+#define	WT_BTREE_UPGRADE	0x080000 /* Handle is for upgrade */
+#define	WT_BTREE_VERIFY		0x100000 /* Handle is for verify */
 	uint32_t flags;
 };
 
diff --git a/src/include/btree.i b/src/include/btree.i
index a9ce4f754a9..74ebf74f1e9 100644
--- a/src/include/btree.i
+++ b/src/include/btree.i
@@ -522,14 +522,22 @@ __wt_page_modify_set(WT_SESSION_IMPL *session, WT_PAGE *page)
 	 * might result in an extra checkpoint that doesn't do any work but it
 	 * shouldn't cause problems; regardless, let's play it safe.)
 	 */
-	if (S2BT(session)->modified == 0) {
+	if (!S2BT(session)->modified) {
 		/* Assert we never dirty a checkpoint handle. */
 		WT_ASSERT(session, session->dhandle->checkpoint == NULL);
 
-		S2BT(session)->modified = 1;
+		S2BT(session)->modified = true;
 		WT_FULL_BARRIER();
 	}
 
+	/*
+	 * There is a possibility of btree being dirty whereas connection being
+	 * clean when entering this function. So make sure to update connection
+	 * to dirty outside a condition on btree modified flag.
+	 */
+	if (!S2C(session)->modified)
+		S2C(session)->modified = true;
+
 	__wt_page_only_modify_set(session, page);
 }
 
diff --git a/src/include/cache.i b/src/include/cache.i
index 4255d04ec37..17ab39e97d2 100644
--- a/src/include/cache.i
+++ b/src/include/cache.i
@@ -355,7 +355,7 @@ __wt_cache_eviction_check(WT_SESSION_IMPL *session, bool busy, bool *didworkp)
 	txn_state = WT_SESSION_TXN_STATE(session);
 	busy = busy || txn_state->id != WT_TXN_NONE ||
 	    session->nhazard > 0 ||
-	    (txn_state->snap_min != WT_TXN_NONE &&
+	    (txn_state->pinned_id != WT_TXN_NONE &&
 	    txn_global->current != txn_global->oldest_id);
 
 	/*
diff --git a/src/include/connection.h b/src/include/connection.h
index e19ad684b24..ce81dcf5976 100644
--- a/src/include/connection.h
+++ b/src/include/connection.h
@@ -352,6 +352,12 @@ struct __wt_connection_impl {
 
 	WT_SESSION_IMPL *meta_ckpt_session;/* Metadata checkpoint session */
 
+	/*
+	 * Is there a data/schema change that needs to be the part of a
+	 * checkpoint.
+	 */
+	bool modified;
+
 	WT_SESSION_IMPL *sweep_session;	   /* Handle sweep session */
 	wt_thread_t	 sweep_tid;	   /* Handle sweep thread */
 	int		 sweep_tid_set;	   /* Handle sweep thread set */
diff --git a/src/include/extern.h b/src/include/extern.h
index 5444b2e9f14..e3cffa4ca3c 100644
--- a/src/include/extern.h
+++ b/src/include/extern.h
@@ -677,7 +677,7 @@ extern uint32_t __wt_log2_int(uint32_t n);
 extern bool __wt_ispo2(uint32_t v);
 extern uint32_t __wt_rduppo2(uint32_t n, uint32_t po2);
 extern void __wt_random_init(WT_RAND_STATE volatile *rnd_state);
-extern int __wt_random_init_seed( WT_SESSION_IMPL *session, WT_RAND_STATE volatile *rnd_state) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern void __wt_random_init_seed( WT_SESSION_IMPL *session, WT_RAND_STATE volatile *rnd_state);
 extern uint32_t __wt_random(WT_RAND_STATE volatile *rnd_state);
 extern int __wt_buf_grow_worker(WT_SESSION_IMPL *session, WT_ITEM *buf, size_t size) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern int __wt_buf_fmt(WT_SESSION_IMPL *session, WT_ITEM *buf, const char *fmt, ...) WT_GCC_FUNC_DECL_ATTRIBUTE((format (printf, 3, 4))) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
diff --git a/src/include/extern_posix.h b/src/include/extern_posix.h
index d2f74d2ffe4..fd94ef0ddf2 100644
--- a/src/include/extern_posix.h
+++ b/src/include/extern_posix.h
@@ -27,5 +27,5 @@ extern void __wt_sleep(uint64_t seconds, uint64_t micro_seconds);
 extern int __wt_thread_create(WT_SESSION_IMPL *session, wt_thread_t *tidret, WT_THREAD_CALLBACK(*func)(void *), void *arg) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern int __wt_thread_join(WT_SESSION_IMPL *session, wt_thread_t tid) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_thread_id(char *buf, size_t buflen);
-extern int __wt_epoch(WT_SESSION_IMPL *session, struct timespec *tsp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern void __wt_epoch(WT_SESSION_IMPL *session, struct timespec *tsp);
 extern void __wt_yield(void);
diff --git a/src/include/extern_win.h b/src/include/extern_win.h
index 8c2b19056e0..f06ee881ece 100644
--- a/src/include/extern_win.h
+++ b/src/include/extern_win.h
@@ -25,7 +25,7 @@ extern void __wt_sleep(uint64_t seconds, uint64_t micro_seconds);
 extern int __wt_thread_create(WT_SESSION_IMPL *session, wt_thread_t *tidret, WT_THREAD_CALLBACK(*func)(void *), void *arg) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern int __wt_thread_join(WT_SESSION_IMPL *session, wt_thread_t tid) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern void __wt_thread_id(char *buf, size_t buflen);
-extern int __wt_epoch(WT_SESSION_IMPL *session, struct timespec *tsp) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
+extern void __wt_epoch(WT_SESSION_IMPL *session, struct timespec *tsp);
 extern int __wt_to_utf16_string( WT_SESSION_IMPL *session, const char*utf8, WT_ITEM **outbuf) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern int __wt_to_utf8_string( WT_SESSION_IMPL *session, const wchar_t*wide, WT_ITEM **outbuf) WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
 extern DWORD __wt_getlasterror(void);
diff --git a/src/include/misc.i b/src/include/misc.i
index f267c7afc91..befd480e085 100644
--- a/src/include/misc.i
+++ b/src/include/misc.i
@@ -33,16 +33,14 @@ __wt_strdup(WT_SESSION_IMPL *session, const char *str, void *retp)
  * __wt_seconds --
  *	Return the seconds since the Epoch.
  */
-static inline int
+static inline void
 __wt_seconds(WT_SESSION_IMPL *session, time_t *timep)
 {
 	struct timespec t;
 
-	WT_RET(__wt_epoch(session, &t));
+	__wt_epoch(session, &t);
 
 	*timep = t.tv_sec;
-
-	return (0);
 }
 
 /*
diff --git a/src/include/stat.h b/src/include/stat.h
index cd0cae16826..68879206851 100644
--- a/src/include/stat.h
+++ b/src/include/stat.h
@@ -420,6 +420,8 @@ struct __wt_connection_stats {
 	int64_t thread_fsync_active;
 	int64_t thread_read_active;
 	int64_t thread_write_active;
+	int64_t application_evict_time;
+	int64_t application_cache_time;
 	int64_t page_busy_blocked;
 	int64_t page_forcible_evict_blocked;
 	int64_t page_locked_blocked;
@@ -437,6 +439,7 @@ struct __wt_connection_stats {
 	int64_t txn_checkpoint_scrub_time;
 	int64_t txn_checkpoint_time_total;
 	int64_t txn_checkpoint;
+	int64_t txn_checkpoint_skipped;
 	int64_t txn_fail_cache;
 	int64_t txn_checkpoint_fsync_post;
 	int64_t txn_checkpoint_fsync_post_duration;
diff --git a/src/include/txn.h b/src/include/txn.h
index 2e41ae8620d..8128e8e4cc2 100644
--- a/src/include/txn.h
+++ b/src/include/txn.h
@@ -49,9 +49,9 @@
 	WT_ASSERT((s), (s)->txn.forced_iso > 0);                        \
 	(s)->txn.forced_iso--;						\
 	WT_ASSERT((s), txn_state->id == saved_state.id &&		\
-	    (txn_state->snap_min == saved_state.snap_min ||		\
-	    saved_state.snap_min == WT_TXN_NONE));			\
-	txn_state->snap_min = saved_state.snap_min;			\
+	    (txn_state->pinned_id == saved_state.pinned_id ||		\
+	    saved_state.pinned_id == WT_TXN_NONE));			\
+	txn_state->pinned_id = saved_state.pinned_id;			\
 } while (0)
 
 struct __wt_named_snapshot {
@@ -59,14 +59,14 @@ struct __wt_named_snapshot {
 
 	TAILQ_ENTRY(__wt_named_snapshot) q;
 
-	uint64_t snap_min, snap_max;
+	uint64_t pinned_id, snap_min, snap_max;
 	uint64_t *snapshot;
 	uint32_t snapshot_count;
 };
 
 struct WT_COMPILER_TYPE_ALIGN(WT_CACHE_LINE_ALIGNMENT) __wt_txn_state {
 	volatile uint64_t id;
-	volatile uint64_t snap_min;
+	volatile uint64_t pinned_id;
 };
 
 struct __wt_txn_global {
diff --git a/src/include/txn.i b/src/include/txn.i
index 1a8851a9a2a..cf7e2eafc65 100644
--- a/src/include/txn.i
+++ b/src/include/txn.i
@@ -309,7 +309,7 @@ __wt_txn_idle_cache_check(WT_SESSION_IMPL *session)
 	 * WT_TXN_HAS_SNAPSHOT.
 	 */
 	if (F_ISSET(txn, WT_TXN_RUNNING) &&
-	    !F_ISSET(txn, WT_TXN_HAS_ID) && txn_state->snap_min == WT_TXN_NONE)
+	    !F_ISSET(txn, WT_TXN_HAS_ID) && txn_state->pinned_id == WT_TXN_NONE)
 		WT_RET(__wt_cache_eviction_check(session, false, NULL));
 
 	return (0);
@@ -480,8 +480,8 @@ __wt_txn_cursor_op(WT_SESSION_IMPL *session)
 	 * positioned on a value, it can't be freed.
 	 */
 	if (txn->isolation == WT_ISO_READ_UNCOMMITTED) {
-		if (txn_state->snap_min == WT_TXN_NONE)
-			txn_state->snap_min = txn_global->last_running;
+		if (txn_state->pinned_id == WT_TXN_NONE)
+			txn_state->pinned_id = txn_global->last_running;
 	} else if (!F_ISSET(txn, WT_TXN_HAS_SNAPSHOT))
 		WT_RET(__wt_txn_get_snapshot(session));
 
diff --git a/src/include/wiredtiger.in b/src/include/wiredtiger.in
index f4763a113f1..2b71a580532 100644
--- a/src/include/wiredtiger.in
+++ b/src/include/wiredtiger.in
@@ -1069,6 +1069,11 @@ struct __wt_session {
 	 * Permitted values are \c "none"\, \c "english"\, \c "utf8<file>" or \c
 	 * "utf16<file>". See @ref huffman for more information., a string;
 	 * default \c none.}
+	 * @config{ignore_in_memory_cache_size, allow update and insert
+	 * operations to proceed even if the cache is already at capacity.  Only
+	 * valid in conjunction with in-memory databases.  Should be used with
+	 * caution - this configuration allows WiredTiger to consume memory over
+	 * the configured cache limit., a boolean flag; default \c false.}
 	 * @config{immutable, configure the index to be immutable - that is an
 	 * index is not changed by any update to a record in the table., a
 	 * boolean flag; default \c false.}
@@ -1815,14 +1820,13 @@ struct __wt_connection {
 	 * default \c 5.}
 	 * @config{eviction_dirty_target, perform eviction in worker threads
 	 * when the cache contains at least this much dirty content\, expressed
-	 * as a percentage of the total cache size.  Ignored if \c in_memory is
-	 * \c true., an integer between 1 and 99; default \c 5.}
+	 * as a percentage of the total cache size., an integer between 1 and
+	 * 99; default \c 5.}
 	 * @config{eviction_dirty_trigger, trigger application threads to
 	 * perform eviction when the cache contains at least this much dirty
 	 * content\, expressed as a percentage of the total cache size.  This
-	 * setting only alters behavior if it is lower than eviction_trigger.
-	 * Ignored if \c in_memory is \c true., an integer between 1 and 99;
-	 * default \c 20.}
+	 * setting only alters behavior if it is lower than eviction_trigger.,
+	 * an integer between 1 and 99; default \c 20.}
 	 * @config{eviction_target, perform eviction in worker threads when the
 	 * cache contains at least this much content\, expressed as a percentage
 	 * of the total cache size.  Must be less than \c eviction_trigger., an
@@ -2281,13 +2285,12 @@ struct __wt_connection {
  * is \c true., an integer between 0 and 99; default \c 5.}
  * @config{eviction_dirty_target, perform eviction in worker threads when the
  * cache contains at least this much dirty content\, expressed as a percentage
- * of the total cache size.  Ignored if \c in_memory is \c true., an integer
- * between 1 and 99; default \c 5.}
+ * of the total cache size., an integer between 1 and 99; default \c 5.}
  * @config{eviction_dirty_trigger, trigger application threads to perform
  * eviction when the cache contains at least this much dirty content\, expressed
  * as a percentage of the total cache size.  This setting only alters behavior
- * if it is lower than eviction_trigger.  Ignored if \c in_memory is \c true.,
- * an integer between 1 and 99; default \c 20.}
+ * if it is lower than eviction_trigger., an integer between 1 and 99; default
+ * \c 20.}
  * @config{eviction_target, perform eviction in worker threads when the cache
  * contains at least this much content\, expressed as a percentage of the total
  * cache size.  Must be less than \c eviction_trigger., an integer between 10
@@ -4591,67 +4594,76 @@ extern int wiredtiger_extension_terminate(WT_CONNECTION *connection);
 #define	WT_STAT_CONN_THREAD_READ_ACTIVE			1186
 /*! thread-state: active filesystem write calls */
 #define	WT_STAT_CONN_THREAD_WRITE_ACTIVE		1187
+/*! thread-yield: application thread time evicting (usecs) */
+#define	WT_STAT_CONN_APPLICATION_EVICT_TIME		1188
+/*! thread-yield: application thread time waiting for cache (usecs) */
+#define	WT_STAT_CONN_APPLICATION_CACHE_TIME		1189
 /*! thread-yield: page acquire busy blocked */
-#define	WT_STAT_CONN_PAGE_BUSY_BLOCKED			1188
+#define	WT_STAT_CONN_PAGE_BUSY_BLOCKED			1190
 /*! thread-yield: page acquire eviction blocked */
-#define	WT_STAT_CONN_PAGE_FORCIBLE_EVICT_BLOCKED	1189
+#define	WT_STAT_CONN_PAGE_FORCIBLE_EVICT_BLOCKED	1191
 /*! thread-yield: page acquire locked blocked */
-#define	WT_STAT_CONN_PAGE_LOCKED_BLOCKED		1190
+#define	WT_STAT_CONN_PAGE_LOCKED_BLOCKED		1192
 /*! thread-yield: page acquire read blocked */
-#define	WT_STAT_CONN_PAGE_READ_BLOCKED			1191
+#define	WT_STAT_CONN_PAGE_READ_BLOCKED			1193
 /*! thread-yield: page acquire time sleeping (usecs) */
-#define	WT_STAT_CONN_PAGE_SLEEP				1192
+#define	WT_STAT_CONN_PAGE_SLEEP				1194
 /*! transaction: number of named snapshots created */
-#define	WT_STAT_CONN_TXN_SNAPSHOTS_CREATED		1193
+#define	WT_STAT_CONN_TXN_SNAPSHOTS_CREATED		1195
 /*! transaction: number of named snapshots dropped */
-#define	WT_STAT_CONN_TXN_SNAPSHOTS_DROPPED		1194
+#define	WT_STAT_CONN_TXN_SNAPSHOTS_DROPPED		1196
 /*! transaction: transaction begins */
-#define	WT_STAT_CONN_TXN_BEGIN				1195
+#define	WT_STAT_CONN_TXN_BEGIN				1197
 /*! transaction: transaction checkpoint currently running */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_RUNNING		1196
+#define	WT_STAT_CONN_TXN_CHECKPOINT_RUNNING		1198
 /*! transaction: transaction checkpoint generation */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_GENERATION		1197
+#define	WT_STAT_CONN_TXN_CHECKPOINT_GENERATION		1199
 /*! transaction: transaction checkpoint max time (msecs) */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_TIME_MAX		1198
+#define	WT_STAT_CONN_TXN_CHECKPOINT_TIME_MAX		1200
 /*! transaction: transaction checkpoint min time (msecs) */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_TIME_MIN		1199
+#define	WT_STAT_CONN_TXN_CHECKPOINT_TIME_MIN		1201
 /*! transaction: transaction checkpoint most recent time (msecs) */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_TIME_RECENT		1200
+#define	WT_STAT_CONN_TXN_CHECKPOINT_TIME_RECENT		1202
 /*! transaction: transaction checkpoint scrub dirty target */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_SCRUB_TARGET	1201
+#define	WT_STAT_CONN_TXN_CHECKPOINT_SCRUB_TARGET	1203
 /*! transaction: transaction checkpoint scrub time (msecs) */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_SCRUB_TIME		1202
+#define	WT_STAT_CONN_TXN_CHECKPOINT_SCRUB_TIME		1204
 /*! transaction: transaction checkpoint total time (msecs) */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_TIME_TOTAL		1203
+#define	WT_STAT_CONN_TXN_CHECKPOINT_TIME_TOTAL		1205
 /*! transaction: transaction checkpoints */
-#define	WT_STAT_CONN_TXN_CHECKPOINT			1204
+#define	WT_STAT_CONN_TXN_CHECKPOINT			1206
+/*!
+ * transaction: transaction checkpoints skipped because database was
+ * clean
+ */
+#define	WT_STAT_CONN_TXN_CHECKPOINT_SKIPPED		1207
 /*! transaction: transaction failures due to cache overflow */
-#define	WT_STAT_CONN_TXN_FAIL_CACHE			1205
+#define	WT_STAT_CONN_TXN_FAIL_CACHE			1208
 /*!
  * transaction: transaction fsync calls for checkpoint after allocating
  * the transaction ID
  */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_FSYNC_POST		1206
+#define	WT_STAT_CONN_TXN_CHECKPOINT_FSYNC_POST		1209
 /*!
  * transaction: transaction fsync duration for checkpoint after
  * allocating the transaction ID (usecs)
  */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_FSYNC_POST_DURATION	1207
+#define	WT_STAT_CONN_TXN_CHECKPOINT_FSYNC_POST_DURATION	1210
 /*! transaction: transaction range of IDs currently pinned */
-#define	WT_STAT_CONN_TXN_PINNED_RANGE			1208
+#define	WT_STAT_CONN_TXN_PINNED_RANGE			1211
 /*! transaction: transaction range of IDs currently pinned by a checkpoint */
-#define	WT_STAT_CONN_TXN_PINNED_CHECKPOINT_RANGE	1209
+#define	WT_STAT_CONN_TXN_PINNED_CHECKPOINT_RANGE	1212
 /*!
  * transaction: transaction range of IDs currently pinned by named
  * snapshots
  */
-#define	WT_STAT_CONN_TXN_PINNED_SNAPSHOT_RANGE		1210
+#define	WT_STAT_CONN_TXN_PINNED_SNAPSHOT_RANGE		1213
 /*! transaction: transaction sync calls */
-#define	WT_STAT_CONN_TXN_SYNC				1211
+#define	WT_STAT_CONN_TXN_SYNC				1214
 /*! transaction: transactions committed */
-#define	WT_STAT_CONN_TXN_COMMIT				1212
+#define	WT_STAT_CONN_TXN_COMMIT				1215
 /*! transaction: transactions rolled back */
-#define	WT_STAT_CONN_TXN_ROLLBACK			1213
+#define	WT_STAT_CONN_TXN_ROLLBACK			1216
 
 /*!
  * @}
diff --git a/src/log/log.c b/src/log/log.c
index b0c789f0f9e..00e4ea5f441 100644
--- a/src/log/log.c
+++ b/src/log/log.c
@@ -128,9 +128,9 @@ __wt_log_force_sync(WT_SESSION_IMPL *session, WT_LSN *min_lsn)
 		    "log_force_sync: sync directory %s to LSN %" PRIu32
 		    "/%" PRIu32,
 		    log->log_dir_fh->name, min_lsn->l.file, min_lsn->l.offset);
-		WT_ERR(__wt_epoch(session, &fsync_start));
+		__wt_epoch(session, &fsync_start);
 		WT_ERR(__wt_fsync(session, log->log_dir_fh, true));
-		WT_ERR(__wt_epoch(session, &fsync_stop));
+		__wt_epoch(session, &fsync_stop);
 		fsync_duration_usecs = WT_TIMEDIFF_US(fsync_stop, fsync_start);
 		log->sync_dir_lsn = *min_lsn;
 		WT_STAT_CONN_INCR(session, log_sync_dir);
@@ -152,9 +152,9 @@ __wt_log_force_sync(WT_SESSION_IMPL *session, WT_LSN *min_lsn)
 		__wt_verbose(session, WT_VERB_LOG,
 		    "log_force_sync: sync %s to LSN %" PRIu32 "/%" PRIu32,
 		    log_fh->name, min_lsn->l.file, min_lsn->l.offset);
-		WT_ERR(__wt_epoch(session, &fsync_start));
+		__wt_epoch(session, &fsync_start);
 		WT_ERR(__wt_fsync(session, log_fh, true));
-		WT_ERR(__wt_epoch(session, &fsync_stop));
+		__wt_epoch(session, &fsync_stop);
 		fsync_duration_usecs = WT_TIMEDIFF_US(fsync_stop, fsync_start);
 		log->sync_lsn = *min_lsn;
 		WT_STAT_CONN_INCR(session, log_sync);
@@ -1478,9 +1478,9 @@ __wt_log_release(WT_SESSION_IMPL *session, WT_LOGSLOT *slot, bool *freep)
 			    "/%" PRIu32,
 			    log->log_dir_fh->name,
 			    sync_lsn.l.file, sync_lsn.l.offset);
-			WT_ERR(__wt_epoch(session, &fsync_start));
+			__wt_epoch(session, &fsync_start);
 			WT_ERR(__wt_fsync(session, log->log_dir_fh, true));
-			WT_ERR(__wt_epoch(session, &fsync_stop));
+			__wt_epoch(session, &fsync_stop);
 			fsync_duration_usecs =
 			    WT_TIMEDIFF_US(fsync_stop, fsync_start);
 			log->sync_dir_lsn = sync_lsn;
@@ -1500,9 +1500,9 @@ __wt_log_release(WT_SESSION_IMPL *session, WT_LOGSLOT *slot, bool *freep)
 			    log->log_fh->name,
 			    sync_lsn.l.file, sync_lsn.l.offset);
 			WT_STAT_CONN_INCR(session, log_sync);
-			WT_ERR(__wt_epoch(session, &fsync_start));
+			__wt_epoch(session, &fsync_start);
 			WT_ERR(__wt_fsync(session, log->log_fh, true));
-			WT_ERR(__wt_epoch(session, &fsync_stop));
+			__wt_epoch(session, &fsync_stop);
 			fsync_duration_usecs =
 			    WT_TIMEDIFF_US(fsync_stop, fsync_start);
 			WT_STAT_CONN_INCRV(session,
diff --git a/src/lsm/lsm_cursor.c b/src/lsm/lsm_cursor.c
index e98f59e7b05..b9a6dd18b7a 100644
--- a/src/lsm/lsm_cursor.c
+++ b/src/lsm/lsm_cursor.c
@@ -165,8 +165,7 @@ __clsm_enter(WT_CURSOR_LSM *clsm, bool reset, bool update)
 	WT_LSM_TREE *lsm_tree;
 	WT_SESSION_IMPL *session;
 	WT_TXN *txn;
-	uint64_t *switch_txnp;
-	uint64_t snap_min;
+	uint64_t pinned_id, *switchp;
 
 	lsm_tree = clsm->lsm_tree;
 	session = (WT_SESSION_IMPL *)clsm->iface.session;
@@ -226,8 +225,8 @@ __clsm_enter(WT_CURSOR_LSM *clsm, bool reset, bool update)
 			 * that overlaps with our snapshot is a potential
 			 * conflict.
 			 *
-			 * Note that the global snap_min is correct here: it
-			 * tracks concurrent transactions excluding special
+			 * Note that the pinned ID is correct here: it tracks
+			 * concurrent transactions excluding special
 			 * transactions such as checkpoint (which we can't
 			 * conflict with because checkpoint only writes the
 			 * metadata, which is not an LSM tree).
@@ -237,17 +236,17 @@ __clsm_enter(WT_CURSOR_LSM *clsm, bool reset, bool update)
 			    F_ISSET(clsm, WT_CLSM_OPEN_SNAPSHOT)) {
 				WT_ASSERT(session,
 				    F_ISSET(txn, WT_TXN_HAS_SNAPSHOT));
-				snap_min =
-				    WT_SESSION_TXN_STATE(session)->snap_min;
-				for (switch_txnp =
+				pinned_id =
+				    WT_SESSION_TXN_STATE(session)->pinned_id;
+				for (switchp =
 				    &clsm->switch_txn[clsm->nchunks - 2];
 				    clsm->nupdates < clsm->nchunks;
-				    clsm->nupdates++, switch_txnp--) {
-					if (WT_TXNID_LT(*switch_txnp, snap_min))
+				    clsm->nupdates++, switchp--) {
+					if (WT_TXNID_LT(*switchp, pinned_id))
 						break;
 					WT_ASSERT(session,
 					    !__wt_txn_visible_all(
-					    session, *switch_txnp));
+					    session, *switchp));
 				}
 			}
 		}
diff --git a/src/lsm/lsm_manager.c b/src/lsm/lsm_manager.c
index 5a5140b9c3a..0a5f4fdd8b5 100644
--- a/src/lsm/lsm_manager.c
+++ b/src/lsm/lsm_manager.c
@@ -392,7 +392,7 @@ __lsm_manager_run_server(WT_SESSION_IMPL *session)
 		TAILQ_FOREACH(lsm_tree, &S2C(session)->lsmqh, q) {
 			if (!lsm_tree->active)
 				continue;
-			WT_ERR(__wt_epoch(session, &now));
+			__wt_epoch(session, &now);
 			pushms = lsm_tree->work_push_ts.tv_sec == 0 ? 0 :
 			    WT_TIMEDIFF_MS(now, lsm_tree->work_push_ts);
 			fillms = 3 * lsm_tree->chunk_fill_ms;
@@ -651,7 +651,7 @@ __wt_lsm_manager_push_entry(WT_SESSION_IMPL *session,
 		return (0);
 	}
 
-	WT_RET(__wt_epoch(session, &lsm_tree->work_push_ts));
+	__wt_epoch(session, &lsm_tree->work_push_ts);
 	WT_RET(__wt_calloc_one(session, &entry));
 	entry->type = type;
 	entry->flags = flags;
diff --git a/src/lsm/lsm_merge.c b/src/lsm/lsm_merge.c
index 4bbfcfd4411..493855d489a 100644
--- a/src/lsm/lsm_merge.c
+++ b/src/lsm/lsm_merge.c
@@ -54,7 +54,7 @@ __lsm_merge_aggressive_clear(WT_LSM_TREE *lsm_tree)
  * __lsm_merge_aggressive_update --
  *	Update the merge aggressiveness for an LSM tree.
  */
-static int
+static void
 __lsm_merge_aggressive_update(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree)
 {
 	struct timespec now;
@@ -72,7 +72,7 @@ __lsm_merge_aggressive_update(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree)
 	if (!lsm_tree->modified ||
 	    F_ISSET(lsm_tree, WT_LSM_TREE_COMPACTING)) {
 		lsm_tree->merge_aggressiveness = 10;
-		return (0);
+		return;
 	}
 
 	/*
@@ -81,7 +81,7 @@ __lsm_merge_aggressive_update(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree)
 	 */
 	if (lsm_tree->chunks_flushed <= lsm_tree->merge_min) {
 		__lsm_merge_aggressive_clear(lsm_tree);
-		return (0);
+		return;
 	}
 
 	/*
@@ -91,10 +91,10 @@ __lsm_merge_aggressive_update(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree)
 	 */
 	if (!F_ISSET(lsm_tree, WT_LSM_TREE_AGGRESSIVE_TIMER)) {
 		F_SET(lsm_tree, WT_LSM_TREE_AGGRESSIVE_TIMER);
-		return (__wt_epoch(session, &lsm_tree->merge_aggressive_ts));
+		__wt_epoch(session, &lsm_tree->merge_aggressive_ts);
 	}
 
-	WT_RET(__wt_epoch(session, &now));
+	__wt_epoch(session, &now);
 	msec_since_last_merge =
 	    WT_TIMEDIFF_MS(now, lsm_tree->merge_aggressive_ts);
 
@@ -113,7 +113,7 @@ __lsm_merge_aggressive_update(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree)
 	 * generates a variable load.
 	 */
 	if (msec_since_last_merge < msec_to_create_merge)
-		return (0);
+		return;
 
 	/*
 	 * Bump how aggressively we look for merges based on how long since
@@ -134,7 +134,6 @@ __lsm_merge_aggressive_update(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree)
 		    msec_since_last_merge, lsm_tree->chunk_fill_ms);
 		lsm_tree->merge_aggressiveness = new_aggressive;
 	}
-	return (0);
 }
 
 /*
@@ -326,7 +325,7 @@ retry_find:
 			goto retry_find;
 		}
 		/* Consider getting aggressive if no merge was found */
-		WT_RET(__lsm_merge_aggressive_update(session, lsm_tree));
+		__lsm_merge_aggressive_update(session, lsm_tree);
 		return (WT_NOTFOUND);
 	}
 
diff --git a/src/lsm/lsm_tree.c b/src/lsm/lsm_tree.c
index db9fd581110..0054dcd1583 100644
--- a/src/lsm/lsm_tree.c
+++ b/src/lsm/lsm_tree.c
@@ -265,7 +265,7 @@ __wt_lsm_tree_setup_chunk(
     WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree, WT_LSM_CHUNK *chunk)
 {
 	WT_ASSERT(session, F_ISSET(session, WT_SESSION_LOCKED_SCHEMA));
-	WT_RET(__wt_epoch(session, &chunk->create_ts));
+	__wt_epoch(session, &chunk->create_ts);
 
 	WT_RET(__wt_lsm_tree_chunk_name(
 	    session, lsm_tree, chunk->id, &chunk->uri));
@@ -496,7 +496,7 @@ __lsm_tree_open(WT_SESSION_IMPL *session,
 	lsm_tree->queue_ref = 0;
 
 	/* Set a flush timestamp as a baseline. */
-	WT_ERR(__wt_epoch(session, &lsm_tree->last_flush_ts));
+	__wt_epoch(session, &lsm_tree->last_flush_ts);
 
 	/* Now the tree is setup, make it visible to others. */
 	TAILQ_INSERT_HEAD(&S2C(session)->lsmqh, lsm_tree, q);
@@ -1139,7 +1139,7 @@ __wt_lsm_compact(WT_SESSION_IMPL *session, const char *name, bool *skipp)
 		return (0);
 	}
 
-	WT_ERR(__wt_seconds(session, &begin));
+	__wt_seconds(session, &begin);
 
 	/*
 	 * Compacting has two distinct phases.
@@ -1267,7 +1267,7 @@ __wt_lsm_compact(WT_SESSION_IMPL *session, const char *name, bool *skipp)
 				break;
 		}
 		__wt_sleep(1, 0);
-		WT_ERR(__wt_seconds(session, &end));
+		__wt_seconds(session, &end);
 		if (session->compact->max_time > 0 &&
 		    session->compact->max_time < (uint64_t)(end - begin)) {
 			WT_ERR(ETIMEDOUT);
diff --git a/src/lsm/lsm_work_unit.c b/src/lsm/lsm_work_unit.c
index 72bcf56b3c4..917104031fc 100644
--- a/src/lsm/lsm_work_unit.c
+++ b/src/lsm/lsm_work_unit.c
@@ -358,7 +358,7 @@ __wt_lsm_checkpoint_chunk(WT_SESSION_IMPL *session,
 	WT_ERR(__wt_lsm_tree_set_chunk_size(session, chunk));
 
 	/* Update the flush timestamp to help track ongoing progress. */
-	WT_ERR(__wt_epoch(session, &lsm_tree->last_flush_ts));
+	__wt_epoch(session, &lsm_tree->last_flush_ts);
 	++lsm_tree->chunks_flushed;
 
 	/* Lock the tree, mark the chunk as on disk and update the metadata. */
diff --git a/src/meta/meta_ckpt.c b/src/meta/meta_ckpt.c
index 2b7719c3241..b985104c2eb 100644
--- a/src/meta/meta_ckpt.c
+++ b/src/meta/meta_ckpt.c
@@ -424,7 +424,7 @@ __wt_meta_ckptlist_set(WT_SESSION_IMPL *session,
 			 * guaranteed, a time_t has to be an arithmetic type,
 			 * but not an integral type.
 			 */
-			WT_ERR(__wt_seconds(session, &secs));
+			__wt_seconds(session, &secs);
 			ckpt->sec = (uintmax_t)secs;
 		}
 		if (strcmp(ckpt->name, WT_CHECKPOINT) == 0)
diff --git a/src/os_posix/os_mtx_cond.c b/src/os_posix/os_mtx_cond.c
index b25bb8c25d1..842bb6eeec9 100644
--- a/src/os_posix/os_mtx_cond.c
+++ b/src/os_posix/os_mtx_cond.c
@@ -63,7 +63,7 @@ __wt_cond_wait_signal(
 	locked = true;
 
 	if (usecs > 0) {
-		WT_ERR(__wt_epoch(session, &ts));
+		__wt_epoch(session, &ts);
 		ts.tv_sec += (time_t)
 		    (((uint64_t)ts.tv_nsec + WT_THOUSAND * usecs) / WT_BILLION);
 		ts.tv_nsec = (long)
diff --git a/src/os_posix/os_time.c b/src/os_posix/os_time.c
index b1b22a8e684..c7ae881af97 100644
--- a/src/os_posix/os_time.c
+++ b/src/os_posix/os_time.c
@@ -12,26 +12,26 @@
  * __wt_epoch --
  *	Return the time since the Epoch.
  */
-int
+void
 __wt_epoch(WT_SESSION_IMPL *session, struct timespec *tsp)
 {
 	WT_DECL_RET;
 
 #if defined(HAVE_CLOCK_GETTIME)
-	WT_SYSCALL(clock_gettime(CLOCK_REALTIME, tsp), ret);
+	WT_SYSCALL_RETRY(clock_gettime(CLOCK_REALTIME, tsp), ret);
 	if (ret == 0)
-		return (0);
-	WT_RET_MSG(session, ret, "clock_gettime");
+		return;
+	WT_PANIC_MSG(session, ret, "clock_gettime");
 #elif defined(HAVE_GETTIMEOFDAY)
 	struct timeval v;
 
-	WT_SYSCALL(gettimeofday(&v, NULL), ret);
+	WT_SYSCALL_RETRY(gettimeofday(&v, NULL), ret);
 	if (ret == 0) {
 		tsp->tv_sec = v.tv_sec;
 		tsp->tv_nsec = v.tv_usec * WT_THOUSAND;
-		return (0);
+		return;
 	}
-	WT_RET_MSG(session, ret, "gettimeofday");
+	WT_PANIC_MSG(session, ret, "gettimeofday");
 #else
 	NO TIME-OF-DAY IMPLEMENTATION: see src/os_posix/os_time.c
 #endif
diff --git a/src/os_win/os_time.c b/src/os_win/os_time.c
index e784b5d8a36..6aa5b3719f6 100644
--- a/src/os_win/os_time.c
+++ b/src/os_win/os_time.c
@@ -12,11 +12,11 @@
  * __wt_epoch --
  *	Return the time since the Epoch.
  */
-int
+void
 __wt_epoch(WT_SESSION_IMPL *session, struct timespec *tsp)
 {
-	uint64_t ns100;
 	FILETIME time;
+	uint64_t ns100;
 
 	WT_UNUSED(session);
 
@@ -26,8 +26,6 @@ __wt_epoch(WT_SESSION_IMPL *session, struct timespec *tsp)
 	    - 116444736000000000LL;
 	tsp->tv_sec = ns100 / 10000000;
 	tsp->tv_nsec = (long)((ns100 % 10000000) * 100);
-
-	return (0);
 }
 
 /*
diff --git a/src/reconcile/rec_write.c b/src/reconcile/rec_write.c
index 9c38c535301..810f3fd976b 100644
--- a/src/reconcile/rec_write.c
+++ b/src/reconcile/rec_write.c
@@ -451,19 +451,18 @@ __wt_reconcile(WT_SESSION_IMPL *session,
 	}
 
 	/*
-	 * When application threads perform eviction, don't cache block manager
-	 * or reconciliation structures (even across calls), we can have a
-	 * significant number of application threads doing eviction at the same
-	 * time with large items. We ignore checkpoints, once the checkpoint
-	 * completes, all unnecessary session resources will be discarded.
+	 * When threads perform eviction, don't cache block manager or
+	 * reconciliation structures (even across calls), we can have a
+	 * significant number of threads doing eviction at the same time with
+	 * large items. We ignore checkpoints, once the checkpoint completes,
+	 * all unnecessary session resources will be discarded.
 	 *
-	 * Even in application threads doing checkpoints or in internal threads
-	 * doing any reconciliation, clean up reconciliation resources. Some
-	 * workloads have millions of boundary structures in a reconciliation
-	 * and we don't want to tie that memory down, even across calls.
+	 * Even in application threads doing checkpoints, clean up
+	 * reconciliation resources. Some workloads have millions of boundary
+	 * structures in a reconciliation and we don't want to tie that memory
+	 * down, even across calls.
 	 */
-	if (WT_SESSION_IS_CHECKPOINT(session) ||
-	    F_ISSET(session, WT_SESSION_INTERNAL))
+	if (WT_SESSION_IS_CHECKPOINT(session))
 		__rec_bnd_cleanup(session, r, false);
 	else {
 		/*
@@ -564,10 +563,12 @@ __rec_write_status(WT_SESSION_IMPL *session, WT_RECONCILE *r, WT_PAGE *page)
 		 * barrier after the change for clarity (the requirement is the
 		 * flag be set before a subsequent checkpoint reads it, and
 		 * as the current checkpoint is waiting on this reconciliation
-		 * to complete, there's no risk of that happening)
+		 * to complete, there's no risk of that happening).
 		 */
-		btree->modified = 1;
+		btree->modified = true;
 		WT_FULL_BARRIER();
+		if (!S2C(session)->modified)
+			S2C(session)->modified = true;
 
 		/*
 		 * Eviction should only be here if following the save/restore
@@ -3335,7 +3336,7 @@ supd_check_complete:
 		__wt_verbose(session, WT_VERB_SPLIT,
 		    "Reconciliation creating a page with %" PRIu32
 		    " entries, memory footprint %" WT_SIZET_FMT
-		    ", page count %" PRIu32 ", %s, split state: %d\n",
+		    ", page count %" PRIu32 ", %s, split state: %d",
 		    r->entries, r->page->memory_footprint, r->bnd_next,
 		    F_ISSET(r, WT_EVICTING) ? "evict" : "checkpoint",
 		    r->bnd_state);
diff --git a/src/session/session_api.c b/src/session/session_api.c
index 0d3fcad3184..d3432c19ef3 100644
--- a/src/session/session_api.c
+++ b/src/session/session_api.c
@@ -68,9 +68,10 @@ __wt_session_copy_values(WT_SESSION_IMPL *session)
 			 * unless the cursor is reading from a checkpoint.
 			 */
 			WT_TXN_STATE *txn_state = WT_SESSION_TXN_STATE(session);
-			WT_ASSERT(session, txn_state->snap_min != WT_TXN_NONE ||
-			   (WT_PREFIX_MATCH(cursor->uri, "file:") &&
-			   F_ISSET((WT_CURSOR_BTREE *)cursor, WT_CBT_NO_TXN)));
+			WT_ASSERT(session,
+			    txn_state->pinned_id != WT_TXN_NONE ||
+			    (WT_PREFIX_MATCH(cursor->uri, "file:") &&
+			    F_ISSET((WT_CURSOR_BTREE *)cursor, WT_CBT_NO_TXN)));
 #endif
 
 			F_CLR(cursor, WT_CURSTD_VALUE_INT);
@@ -1417,10 +1418,10 @@ __session_transaction_pinned_range(WT_SESSION *wt_session, uint64_t *prange)
 
 	/* Assign pinned to the lesser of id or snap_min */
 	if (txn_state->id != WT_TXN_NONE &&
-	    WT_TXNID_LT(txn_state->id, txn_state->snap_min))
+	    WT_TXNID_LT(txn_state->id, txn_state->pinned_id))
 		pinned = txn_state->id;
 	else
-		pinned = txn_state->snap_min;
+		pinned = txn_state->pinned_id;
 
 	if (pinned == WT_TXN_NONE)
 		*prange = 0;
@@ -1494,14 +1495,14 @@ __session_transaction_sync(WT_SESSION *wt_session, const char *config)
 	if (timeout_ms == 0)
 		WT_ERR(ETIMEDOUT);
 
-	WT_ERR(__wt_epoch(session, &start));
+	__wt_epoch(session, &start);
 	/*
 	 * Keep checking the LSNs until we find it is stable or we reach
 	 * our timeout.
 	 */
 	while (__wt_log_cmp(&session->bg_sync_lsn, &log->sync_lsn) > 0) {
 		__wt_cond_signal(session, conn->log_file_cond);
-		WT_ERR(__wt_epoch(session, &now));
+		__wt_epoch(session, &now);
 		waited_ms = WT_TIMEDIFF_MS(now, start);
 		if (forever || waited_ms < timeout_ms)
 			/*
diff --git a/src/session/session_compact.c b/src/session/session_compact.c
index f03d5d34bac..66635007723 100644
--- a/src/session/session_compact.c
+++ b/src/session/session_compact.c
@@ -179,17 +179,16 @@ __compact_handle_append(WT_SESSION_IMPL *session, const char *cfg[])
  *	Check if the timeout has been exceeded.
  */
 static int
-__session_compact_check_timeout(
-    WT_SESSION_IMPL *session, struct timespec begin)
+__session_compact_check_timeout(WT_SESSION_IMPL *session, struct timespec begin)
 {
 	struct timespec end;
 
 	if (session->compact->max_time == 0)
 		return (0);
 
-	WT_RET(__wt_epoch(session, &end));
+	__wt_epoch(session, &end);
 	if (session->compact->max_time < WT_TIMEDIFF_SEC(end, begin))
-		WT_RET(ETIMEDOUT);
+		return (ETIMEDOUT);
 	return (0);
 }
 
@@ -219,7 +218,7 @@ __compact_file(WT_SESSION_IMPL *session, const char *cfg[])
 	    session, t, "target=(\"%s\"),force=1", dhandle->name));
 	checkpoint_cfg[1] = t->data;
 
-	WT_ERR(__wt_epoch(session, &start_time));
+	__wt_epoch(session, &start_time);
 
 	/*
 	 * We compact 10% of the file on each pass (but the overall size of the
diff --git a/src/session/session_dhandle.c b/src/session/session_dhandle.c
index e76407567bc..725854c6001 100644
--- a/src/session/session_dhandle.c
+++ b/src/session/session_dhandle.c
@@ -8,8 +8,6 @@
 
 #include "wt_internal.h"
 
-static int __session_dhandle_sweep(WT_SESSION_IMPL *);
-
 /*
  * __session_add_dhandle --
  *	Add a handle to the session's cache.
@@ -371,7 +369,7 @@ __wt_session_close_cache(WT_SESSION_IMPL *session)
  * __session_dhandle_sweep --
  *	Discard any session dhandles that are not open.
  */
-static int
+static void
 __session_dhandle_sweep(WT_SESSION_IMPL *session)
 {
 	WT_CONNECTION_IMPL *conn;
@@ -385,9 +383,9 @@ __session_dhandle_sweep(WT_SESSION_IMPL *session)
 	 * Periodically sweep for dead handles; if we've swept recently, don't
 	 * do it again.
 	 */
-	WT_RET(__wt_seconds(session, &now));
+	__wt_seconds(session, &now);
 	if (difftime(now, session->last_sweep) < conn->sweep_interval)
-		return (0);
+		return;
 	session->last_sweep = now;
 
 	WT_STAT_CONN_INCR(session, dh_session_sweeps);
@@ -408,7 +406,6 @@ __session_dhandle_sweep(WT_SESSION_IMPL *session)
 		}
 		dhandle_cache = dhandle_cache_next;
 	}
-	return (0);
 }
 
 /*
@@ -446,7 +443,7 @@ __session_get_dhandle(
 	}
 
 	/* Sweep the handle list to remove any dead handles. */
-	WT_RET(__session_dhandle_sweep(session));
+	__session_dhandle_sweep(session);
 
 	/*
 	 * We didn't find a match in the session cache, search the shared
diff --git a/src/support/err.c b/src/support/err.c
index 8bfac250b3a..3ecbab1cbe9 100644
--- a/src/support/err.c
+++ b/src/support/err.c
@@ -162,7 +162,6 @@ __wt_eventv(WT_SESSION_IMPL *session, bool msg_event, int error,
 	WT_SESSION *wt_session;
 	struct timespec ts;
 	size_t len, remain, wlen;
-	int prefix_cnt;
 	const char *err, *prefix;
 	char *end, *p, tid[128];
 
@@ -211,44 +210,32 @@ __wt_eventv(WT_SESSION_IMPL *session, bool msg_event, int error,
 	 * name, and the session's name.  Write them as a comma-separate list,
 	 * followed by a colon.
 	 */
-	prefix_cnt = 0;
-	if (__wt_epoch(session, &ts) == 0) {
-		__wt_thread_id(tid, sizeof(tid));
-		remain = WT_PTRDIFF(end, p);
-		wlen = (size_t)snprintf(p, remain,
-		    "[%" PRIuMAX ":%" PRIuMAX "][%s]",
-		    (uintmax_t)ts.tv_sec,
-		    (uintmax_t)ts.tv_nsec / WT_THOUSAND, tid);
-		p = wlen >= remain ? end : p + wlen;
-		prefix_cnt = 1;
-	}
+	__wt_epoch(session, &ts);
+	__wt_thread_id(tid, sizeof(tid));
+	remain = WT_PTRDIFF(end, p);
+	wlen = (size_t)snprintf(p, remain, "[%" PRIuMAX ":%" PRIuMAX "][%s]",
+	    (uintmax_t)ts.tv_sec, (uintmax_t)ts.tv_nsec / WT_THOUSAND, tid);
+	p = wlen >= remain ? end : p + wlen;
+
 	if ((prefix = S2C(session)->error_prefix) != NULL) {
 		remain = WT_PTRDIFF(end, p);
-		wlen = (size_t)snprintf(p, remain,
-		    "%s%s", prefix_cnt == 0 ? "" : ", ", prefix);
+		wlen = (size_t)snprintf(p, remain, ", %s", prefix);
 		p = wlen >= remain ? end : p + wlen;
-		prefix_cnt = 1;
 	}
 	prefix = session->dhandle == NULL ? NULL : session->dhandle->name;
 	if (prefix != NULL) {
 		remain = WT_PTRDIFF(end, p);
-		wlen = (size_t)snprintf(p, remain,
-		    "%s%s", prefix_cnt == 0 ? "" : ", ", prefix);
+		wlen = (size_t)snprintf(p, remain, ", %s", prefix);
 		p = wlen >= remain ? end : p + wlen;
-		prefix_cnt = 1;
 	}
 	if ((prefix = session->name) != NULL) {
 		remain = WT_PTRDIFF(end, p);
-		wlen = (size_t)snprintf(p, remain,
-		    "%s%s", prefix_cnt == 0 ? "" : ", ", prefix);
-		p = wlen >= remain ? end : p + wlen;
-		prefix_cnt = 1;
-	}
-	if (prefix_cnt != 0) {
-		remain = WT_PTRDIFF(end, p);
-		wlen = (size_t)snprintf(p, remain, ": ");
+		wlen = (size_t)snprintf(p, remain, ", %s", prefix);
 		p = wlen >= remain ? end : p + wlen;
 	}
+	remain = WT_PTRDIFF(end, p);
+	wlen = (size_t)snprintf(p, remain, ": ");
+	p = wlen >= remain ? end : p + wlen;
 
 	if (file_name != NULL) {
 		remain = WT_PTRDIFF(end, p);
diff --git a/src/support/rand.c b/src/support/rand.c
index d2e4cd27aab..025b18e4ed3 100644
--- a/src/support/rand.c
+++ b/src/support/rand.c
@@ -66,20 +66,18 @@ __wt_random_init(WT_RAND_STATE volatile * rnd_state)
  * threads and we want each thread to initialize its own random state based
  * on a different random seed.
  */
-int
+void
 __wt_random_init_seed(
     WT_SESSION_IMPL *session, WT_RAND_STATE volatile * rnd_state)
 {
 	struct timespec ts;
 	WT_RAND_STATE rnd;
 
-	WT_RET(__wt_epoch(session, &ts));
+	__wt_epoch(session, &ts);
 	M_W(rnd) = (uint32_t)(ts.tv_nsec + 521288629);
 	M_Z(rnd) = (uint32_t)(ts.tv_nsec + 362436069);
 
 	*rnd_state = rnd;
-
-	return (0);
 }
 
 /*
diff --git a/src/support/stat.c b/src/support/stat.c
index 7150223e6cb..9d440f9ebf3 100644
--- a/src/support/stat.c
+++ b/src/support/stat.c
@@ -706,6 +706,8 @@ static const char * const __stats_connection_desc[] = {
 	"thread-state: active filesystem fsync calls",
 	"thread-state: active filesystem read calls",
 	"thread-state: active filesystem write calls",
+	"thread-yield: application thread time evicting (usecs)",
+	"thread-yield: application thread time waiting for cache (usecs)",
 	"thread-yield: page acquire busy blocked",
 	"thread-yield: page acquire eviction blocked",
 	"thread-yield: page acquire locked blocked",
@@ -723,6 +725,7 @@ static const char * const __stats_connection_desc[] = {
 	"transaction: transaction checkpoint scrub time (msecs)",
 	"transaction: transaction checkpoint total time (msecs)",
 	"transaction: transaction checkpoints",
+	"transaction: transaction checkpoints skipped because database was clean",
 	"transaction: transaction failures due to cache overflow",
 	"transaction: transaction fsync calls for checkpoint after allocating the transaction ID",
 	"transaction: transaction fsync duration for checkpoint after allocating the transaction ID (usecs)",
@@ -950,6 +953,8 @@ __wt_stat_connection_clear_single(WT_CONNECTION_STATS *stats)
 		/* not clearing thread_fsync_active */
 		/* not clearing thread_read_active */
 		/* not clearing thread_write_active */
+	stats->application_evict_time = 0;
+	stats->application_cache_time = 0;
 	stats->page_busy_blocked = 0;
 	stats->page_forcible_evict_blocked = 0;
 	stats->page_locked_blocked = 0;
@@ -967,6 +972,7 @@ __wt_stat_connection_clear_single(WT_CONNECTION_STATS *stats)
 		/* not clearing txn_checkpoint_scrub_time */
 		/* not clearing txn_checkpoint_time_total */
 	stats->txn_checkpoint = 0;
+	stats->txn_checkpoint_skipped = 0;
 	stats->txn_fail_cache = 0;
 	stats->txn_checkpoint_fsync_post = 0;
 		/* not clearing txn_checkpoint_fsync_post_duration */
@@ -1242,6 +1248,10 @@ __wt_stat_connection_aggregate(
 	to->thread_fsync_active += WT_STAT_READ(from, thread_fsync_active);
 	to->thread_read_active += WT_STAT_READ(from, thread_read_active);
 	to->thread_write_active += WT_STAT_READ(from, thread_write_active);
+	to->application_evict_time +=
+	    WT_STAT_READ(from, application_evict_time);
+	to->application_cache_time +=
+	    WT_STAT_READ(from, application_cache_time);
 	to->page_busy_blocked += WT_STAT_READ(from, page_busy_blocked);
 	to->page_forcible_evict_blocked +=
 	    WT_STAT_READ(from, page_forcible_evict_blocked);
@@ -1270,6 +1280,8 @@ __wt_stat_connection_aggregate(
 	to->txn_checkpoint_time_total +=
 	    WT_STAT_READ(from, txn_checkpoint_time_total);
 	to->txn_checkpoint += WT_STAT_READ(from, txn_checkpoint);
+	to->txn_checkpoint_skipped +=
+	    WT_STAT_READ(from, txn_checkpoint_skipped);
 	to->txn_fail_cache += WT_STAT_READ(from, txn_fail_cache);
 	to->txn_checkpoint_fsync_post +=
 	    WT_STAT_READ(from, txn_checkpoint_fsync_post);
diff --git a/src/support/thread_group.c b/src/support/thread_group.c
index f5ddabad7d4..a866d2d01c5 100644
--- a/src/support/thread_group.c
+++ b/src/support/thread_group.c
@@ -60,7 +60,7 @@ __thread_group_grow(
 	while (group->current_threads < new_count) {
 		thread = group->threads[group->current_threads++];
 		__wt_verbose(session, WT_VERB_THREAD_GROUP,
-		    "Starting utility thread: %p:%"PRIu32"\n",
+		    "Starting utility thread: %p:%" PRIu32,
 		    (void *)group, thread->id);
 		F_SET(thread, WT_THREAD_RUN);
 		WT_ASSERT(session, thread->session != NULL);
@@ -100,7 +100,7 @@ __thread_group_shrink(WT_SESSION_IMPL *session,
 		/* Wake threads to ensure they notice the state change */
 		if (thread->tid != 0) {
 			__wt_verbose(session, WT_VERB_THREAD_GROUP,
-			    "Stopping utility thread: %p:%"PRIu32"\n",
+			    "Stopping utility thread: %p:%" PRIu32,
 			    (void *)group, thread->id);
 			F_CLR(thread, WT_THREAD_RUN);
 			__wt_cond_signal(session, group->wait_cond);
@@ -224,7 +224,7 @@ __wt_thread_group_resize(
 
 	__wt_verbose(session, WT_VERB_THREAD_GROUP,
 	    "Resize thread group: %p, from min: %" PRIu32 " -> %" PRIu32
-	    " from max: %" PRIu32 " -> %" PRIu32 "\n",
+	    " from max: %" PRIu32 " -> %" PRIu32,
 	    (void *)group, group->min, new_min, group->max, new_max);
 
 	__wt_writelock(session, group->lock);
@@ -253,7 +253,7 @@ __wt_thread_group_create(
 	cond_alloced = false;
 
 	__wt_verbose(session, WT_VERB_THREAD_GROUP,
-	    "Creating thread group: %p\n", (void *)group);
+	    "Creating thread group: %p", (void *)group);
 
 	WT_RET(__wt_rwlock_alloc(session, &group->lock, "Thread group"));
 	WT_ERR(__wt_cond_alloc(
@@ -286,7 +286,7 @@ __wt_thread_group_destroy(WT_SESSION_IMPL *session, WT_THREAD_GROUP *group)
 	WT_DECL_RET;
 
 	__wt_verbose(session, WT_VERB_THREAD_GROUP,
-	    "Destroying thread group: %p\n", (void *)group);
+	    "Destroying thread group: %p", (void *)group);
 
 	WT_ASSERT(session, __wt_rwlock_islocked(session, group->lock));
 
diff --git a/src/txn/txn.c b/src/txn/txn.c
index 01e0fbbb634..3b24bcd505d 100644
--- a/src/txn/txn.c
+++ b/src/txn/txn.c
@@ -96,11 +96,11 @@ __wt_txn_release_snapshot(WT_SESSION_IMPL *session)
 	txn_state = WT_SESSION_TXN_STATE(session);
 
 	WT_ASSERT(session,
-	    txn_state->snap_min == WT_TXN_NONE ||
+	    txn_state->pinned_id == WT_TXN_NONE ||
 	    session->txn.isolation == WT_ISO_READ_UNCOMMITTED ||
-	    !__wt_txn_visible_all(session, txn_state->snap_min));
+	    !__wt_txn_visible_all(session, txn_state->pinned_id));
 
-	txn_state->snap_min = WT_TXN_NONE;
+	txn_state->pinned_id = WT_TXN_NONE;
 	F_CLR(txn, WT_TXN_HAS_SNAPSHOT);
 }
 
@@ -117,7 +117,7 @@ __wt_txn_get_snapshot(WT_SESSION_IMPL *session)
 	WT_TXN_GLOBAL *txn_global;
 	WT_TXN_STATE *s, *txn_state;
 	uint64_t current_id, id;
-	uint64_t prev_oldest_id, snap_min;
+	uint64_t prev_oldest_id, pinned_id;
 	uint32_t i, n, session_cnt;
 
 	conn = S2C(session);
@@ -135,21 +135,21 @@ __wt_txn_get_snapshot(WT_SESSION_IMPL *session)
 		WT_PAUSE();
 	WT_RET(ret);
 
-	current_id = snap_min = txn_global->current;
+	current_id = pinned_id = txn_global->current;
 	prev_oldest_id = txn_global->oldest_id;
 
 	/*
 	 * Include the checkpoint transaction, if one is running: we should
 	 * ignore any uncommitted changes the checkpoint has written to the
 	 * metadata.  We don't have to keep the checkpoint's changes pinned so
-	 * don't including it in the published snap_min.
+	 * don't including it in the published pinned ID.
 	 */
 	if ((id = txn_global->checkpoint_txnid) != WT_TXN_NONE)
 		txn->snapshot[n++] = id;
 
 	/* For pure read-only workloads, avoid scanning. */
 	if (prev_oldest_id == current_id) {
-		txn_state->snap_min = current_id;
+		txn_state->pinned_id = current_id;
 		/* Check that the oldest ID has not moved in the meantime. */
 		WT_ASSERT(session, prev_oldest_id == txn_global->oldest_id);
 		goto done;
@@ -172,18 +172,18 @@ __wt_txn_get_snapshot(WT_SESSION_IMPL *session)
 		    (id = s->id) != WT_TXN_NONE &&
 		    WT_TXNID_LE(prev_oldest_id, id)) {
 			txn->snapshot[n++] = id;
-			if (WT_TXNID_LT(id, snap_min))
-				snap_min = id;
+			if (WT_TXNID_LT(id, pinned_id))
+				pinned_id = id;
 		}
 	}
 
 	/*
-	 * If we got a new snapshot, update the published snap_min for this
+	 * If we got a new snapshot, update the published pinned ID for this
 	 * session.
 	 */
-	WT_ASSERT(session, WT_TXNID_LE(prev_oldest_id, snap_min));
+	WT_ASSERT(session, WT_TXNID_LE(prev_oldest_id, pinned_id));
 	WT_ASSERT(session, prev_oldest_id == txn_global->oldest_id);
-	txn_state->snap_min = snap_min;
+	txn_state->pinned_id = pinned_id;
 
 done:	__wt_readunlock(session, txn_global->scan_rwlock);
 	__txn_sort_snapshot(session, n, current_id);
@@ -232,13 +232,13 @@ __txn_oldest_scan(WT_SESSION_IMPL *session,
 
 		/*
 		 * !!!
-		 * Note: Don't ignore snap_min values older than the previous
-		 * oldest ID.  Read-uncommitted operations publish snap_min
+		 * Note: Don't ignore pinned ID values older than the previous
+		 * oldest ID.  Read-uncommitted operations publish pinned ID
 		 * values without acquiring the scan lock to protect the global
-		 * table.  See the comment in __wt_txn_cursor_op for
-		 * more details.
+		 * table.  See the comment in __wt_txn_cursor_op for more
+		 * details.
 		 */
-		if ((id = s->snap_min) != WT_TXN_NONE &&
+		if ((id = s->pinned_id) != WT_TXN_NONE &&
 		    WT_TXNID_LT(id, oldest_id)) {
 			oldest_id = id;
 			oldest_session = &conn->sessions[i];
@@ -360,7 +360,7 @@ __wt_txn_update_oldest(WT_SESSION_IMPL *session, uint32_t flags)
 			__wt_verbose(session, WT_VERB_TRANSACTION,
 			    "old snapshot %" PRIu64
 			    " pinned in session %" PRIu32 " [%s]"
-			    " with snap_min %" PRIu64 "\n",
+			    " with snap_min %" PRIu64,
 			    oldest_id, oldest_session->id,
 			    oldest_session->lastop,
 			    oldest_session->txn.snap_min);
@@ -673,7 +673,7 @@ __wt_txn_init(WT_SESSION_IMPL *session)
 	if (S2C(session)->txn_global.states != NULL) {
 		WT_TXN_STATE *txn_state;
 		txn_state = WT_SESSION_TXN_STATE(session);
-		WT_ASSERT(session, txn_state->snap_min == WT_TXN_NONE);
+		WT_ASSERT(session, txn_state->pinned_id == WT_TXN_NONE);
 	}
 #endif
 
@@ -773,7 +773,7 @@ __wt_txn_global_init(WT_SESSION_IMPL *session, const char *cfg[])
 	WT_CACHE_LINE_ALIGNMENT_VERIFY(session, txn_global->states);
 
 	for (i = 0, s = txn_global->states; i < conn->session_size; i++, s++)
-		s->id = s->snap_min = WT_TXN_NONE;
+		s->id = s->pinned_id = WT_TXN_NONE;
 
 	return (0);
 }
diff --git a/src/txn/txn_ckpt.c b/src/txn/txn_ckpt.c
index 3aad95f5a9f..0557e6ce60c 100644
--- a/src/txn/txn_ckpt.c
+++ b/src/txn/txn_ckpt.c
@@ -314,7 +314,7 @@ __checkpoint_update_generation(WT_SESSION_IMPL *session)
  * __checkpoint_reduce_dirty_cache --
  *	Release clean trees from the list cached for checkpoints.
  */
-static int
+static void
 __checkpoint_reduce_dirty_cache(WT_SESSION_IMPL *session)
 {
 	WT_CACHE *cache;
@@ -332,9 +332,9 @@ __checkpoint_reduce_dirty_cache(WT_SESSION_IMPL *session)
 	/* Give up if scrubbing is disabled. */
 	if (cache->eviction_checkpoint_target == 0 ||
 	    cache->eviction_checkpoint_target >= cache->eviction_dirty_trigger)
-		return (0);
+		return;
 
-	WT_RET(__wt_epoch(session, &start));
+	__wt_epoch(session, &start);
 	last = start;
 	bytes_written_last = 0;
 	bytes_written_start = cache->bytes_written;
@@ -345,7 +345,7 @@ __checkpoint_reduce_dirty_cache(WT_SESSION_IMPL *session)
 	 * cache via reconfigure.  This avoids potential divide by zero.
 	 */
 	if (cache_size < 10 * WT_MEGABYTE)
-		return (0);
+		return;
 	stepdown_us = 10000;
 	work_us = 0;
 	progress = false;
@@ -371,7 +371,7 @@ __checkpoint_reduce_dirty_cache(WT_SESSION_IMPL *session)
 			break;
 
 		__wt_sleep(0, stepdown_us / 10);
-		WT_RET(__wt_epoch(session, &stop));
+		__wt_epoch(session, &stop);
 		current_us = WT_TIMEDIFF_US(stop, last);
 		total_ms = WT_TIMEDIFF_MS(stop, start);
 		bytes_written_total =
@@ -427,14 +427,12 @@ __checkpoint_reduce_dirty_cache(WT_SESSION_IMPL *session)
 		    WT_MAX(cache->eviction_dirty_target, current_dirty - delta);
 		WT_STAT_CONN_SET(session, txn_checkpoint_scrub_target,
 		    cache->eviction_scrub_limit);
-		WT_RET(__wt_epoch(session, &last));
+		__wt_epoch(session, &last);
 	}
 
-	WT_RET(__wt_epoch(session, &stop));
+	__wt_epoch(session, &stop);
 	total_ms = WT_TIMEDIFF_MS(stop, start);
 	WT_STAT_CONN_SET(session, txn_checkpoint_scrub_time, total_ms);
-
-	return (0);
 }
 
 /*
@@ -497,7 +495,7 @@ __checkpoint_stats(
  * __checkpoint_verbose_track --
  *	Output a verbose message with timing information
  */
-static int
+static void
 __checkpoint_verbose_track(WT_SESSION_IMPL *session,
     const char *msg, struct timespec *start)
 {
@@ -506,9 +504,9 @@ __checkpoint_verbose_track(WT_SESSION_IMPL *session,
 	uint64_t msec;
 
 	if (!WT_VERBOSE_ISSET(session, WT_VERB_CHECKPOINT))
-		return (0);
+		return;
 
-	WT_RET(__wt_epoch(session, &stop));
+	__wt_epoch(session, &stop);
 
 	/*
 	 * Get time diff in microseconds.
@@ -526,7 +524,6 @@ __checkpoint_verbose_track(WT_SESSION_IMPL *session,
 	WT_UNUSED(msg);
 	WT_UNUSED(start);
 #endif
-	return (0);
 }
 
 /*
@@ -576,7 +573,7 @@ __txn_checkpoint(WT_SESSION_IMPL *session, const char *cfg[])
 	conn->cache->evict_max_page_size = 0;
 
 	/* Initialize the verbose tracking timer */
-	WT_ERR(__wt_epoch(session, &verb_timer));
+	__wt_epoch(session, &verb_timer);
 
 	/*
 	 * Update the global oldest ID so we do all possible cleanup.
@@ -594,18 +591,18 @@ __txn_checkpoint(WT_SESSION_IMPL *session, const char *cfg[])
 	 * Try to reduce the amount of dirty data in cache so there is less
 	 * work do during the critical section of the checkpoint.
 	 */
-	WT_ERR(__checkpoint_reduce_dirty_cache(session));
+	__checkpoint_reduce_dirty_cache(session);
 
 	/* Tell logging that we are about to start a database checkpoint. */
 	if (full && logging)
 		WT_ERR(__wt_txn_checkpoint_log(
 		    session, full, WT_TXN_LOG_CKPT_PREPARE, NULL));
 
-	WT_ERR(__checkpoint_verbose_track(session,
-	    "starting transaction", &verb_timer));
+	__checkpoint_verbose_track(session,
+	    "starting transaction", &verb_timer);
 
 	if (full)
-		WT_ERR(__wt_epoch(session, &start));
+		__wt_epoch(session, &start);
 
 	/*
 	 * Start the checkpoint for real.
@@ -666,6 +663,14 @@ __txn_checkpoint(WT_SESSION_IMPL *session, const char *cfg[])
 	WT_ERR(__wt_txn_id_check(session));
 
 	/*
+	 * Mark the connection as clean. If some data gets modified after
+	 * generating checkpoint transaction id, connection will be reset to
+	 * dirty when reconciliation marks the btree dirty on encountering the
+	 * dirty page.
+	 */
+	conn->modified = false;
+
+	/*
 	 * Save the checkpoint session ID.
 	 *
 	 * We never do checkpoints in the default session (with id zero).
@@ -689,7 +694,7 @@ __txn_checkpoint(WT_SESSION_IMPL *session, const char *cfg[])
 	 */
 	WT_ASSERT(session,
 	    WT_TXNID_LE(txn_global->oldest_id, txn_state->id) &&
-	    WT_TXNID_LE(txn_global->oldest_id, txn_state->snap_min));
+	    WT_TXNID_LE(txn_global->oldest_id, txn_state->pinned_id));
 
 	/*
 	 * Clear our entry from the global transaction session table. Any
@@ -698,7 +703,7 @@ __txn_checkpoint(WT_SESSION_IMPL *session, const char *cfg[])
 	 * can safely ignore the checkpoint ID (see the visible all check for
 	 * details).
 	 */
-	txn_state->id = txn_state->snap_min = WT_TXN_NONE;
+	txn_state->id = txn_state->pinned_id = WT_TXN_NONE;
 	__wt_writeunlock(session, txn_global->scan_rwlock);
 
 	/*
@@ -739,23 +744,22 @@ __txn_checkpoint(WT_SESSION_IMPL *session, const char *cfg[])
 	WT_ERR(__checkpoint_apply(session, cfg, __checkpoint_presync));
 	__wt_evict_server_wake(session);
 
-	WT_ERR(__checkpoint_verbose_track(session,
-	    "committing transaction", &verb_timer));
+	__checkpoint_verbose_track(session,
+	    "committing transaction", &verb_timer);
 
 	/*
 	 * Checkpoints have to hit disk (it would be reasonable to configure for
 	 * lazy checkpoints, but we don't support them yet).
 	 */
-	WT_ERR(__wt_epoch(session, &fsync_start));
+	__wt_epoch(session, &fsync_start);
 	WT_ERR(__checkpoint_apply(session, cfg, __wt_checkpoint_sync));
-	WT_ERR(__wt_epoch(session, &fsync_stop));
+	__wt_epoch(session, &fsync_stop);
 	fsync_duration_usecs = WT_TIMEDIFF_US(fsync_stop, fsync_start);
 	WT_STAT_CONN_INCR(session, txn_checkpoint_fsync_post);
 	WT_STAT_CONN_SET(session,
 	    txn_checkpoint_fsync_post_duration, fsync_duration_usecs);
 
-	WT_ERR(__checkpoint_verbose_track(session,
-	    "sync completed", &verb_timer));
+	__checkpoint_verbose_track(session, "sync completed", &verb_timer);
 
 	/*
 	 * Commit the transaction now that we are sure that all files in the
@@ -793,8 +797,8 @@ __txn_checkpoint(WT_SESSION_IMPL *session, const char *cfg[])
 		    ret = __wt_checkpoint_sync(session, NULL));
 		WT_ERR(ret);
 
-		WT_ERR(__checkpoint_verbose_track(session,
-		    "metadata sync completed", &verb_timer));
+		__checkpoint_verbose_track(session,
+		    "metadata sync completed", &verb_timer);
 	} else
 		WT_WITH_DHANDLE(session,
 		    WT_SESSION_META_DHANDLE(session),
@@ -808,7 +812,7 @@ __txn_checkpoint(WT_SESSION_IMPL *session, const char *cfg[])
 	txn_global->checkpoint_pinned = WT_TXN_NONE;
 
 	if (full) {
-		WT_ERR(__wt_epoch(session, &stop));
+		__wt_epoch(session, &stop);
 		__checkpoint_stats(session, &start, &stop);
 	}
 
@@ -825,6 +829,9 @@ err:	/*
 	 * overwritten the checkpoint, so what ends up on disk is not
 	 * consistent.
 	 */
+	if (ret != 0 && !conn->modified)
+		conn->modified = true;
+
 	session->isolation = txn->isolation = WT_ISO_READ_UNCOMMITTED;
 	if (tracking)
 		WT_TRET(__wt_meta_track_off(session, false, ret != 0));
@@ -1352,9 +1359,13 @@ __checkpoint_tree(
 	 * out of sync with the set of dirty pages (modify is set, but there
 	 * are no dirty pages), we perform a checkpoint without any writes, no
 	 * checkpoint is created, and then things get bad.
+	 * While marking the root page as dirty, we do not want to dirty the
+	 * btree because we are marking the btree as clean just after this call.
+	 * Also, marking the btree dirty at this stage will unnecessarily mark
+	 * the connection as dirty causing checkpoint-skip code to fail.
 	 */
 	WT_ERR(__wt_page_modify_init(session, btree->root.page));
-	__wt_page_modify_set(session, btree->root.page);
+	__wt_page_only_modify_set(session, btree->root.page);
 
 	/*
 	 * Clear the tree's modified flag; any changes before we clear the flag
@@ -1366,7 +1377,7 @@ __checkpoint_tree(
 	 * it sets the modified flag itself.  Use a full barrier so we get the
 	 * store done quickly, this isn't a performance path.
 	 */
-	btree->modified = 0;
+	btree->modified = false;
 	WT_FULL_BARRIER();
 
 	/* Tell logging that a file checkpoint is starting. */
@@ -1440,8 +1451,11 @@ err:	/*
 	 * If the checkpoint didn't complete successfully, make sure the
 	 * tree is marked dirty.
 	 */
-	if (ret != 0 && !btree->modified && was_modified)
-		btree->modified = 1;
+	if (ret != 0 && !btree->modified && was_modified) {
+		btree->modified = true;
+		if (!S2C(session)->modified)
+			S2C(session)->modified = true;
+	}
 
 	__wt_meta_ckptlist_free(session, ckptbase);
 	btree->ckpt = NULL;
diff --git a/src/txn/txn_nsnap.c b/src/txn/txn_nsnap.c
index 8f7e93238de..7ba0cc8700e 100644
--- a/src/txn/txn_nsnap.c
+++ b/src/txn/txn_nsnap.c
@@ -42,9 +42,16 @@ __nsnap_drop_one(WT_SESSION_IMPL *session, WT_CONFIG_ITEM *name)
 		return (WT_NOTFOUND);
 
 	/* Bump the global ID if we are removing the first entry */
-	if (found == TAILQ_FIRST(&txn_global->nsnaph))
+	if (found == TAILQ_FIRST(&txn_global->nsnaph)) {
+		WT_ASSERT(session, !__wt_txn_visible_all(
+		    session, txn_global->nsnap_oldest_id));
 		txn_global->nsnap_oldest_id = (TAILQ_NEXT(found, q) != NULL) ?
-		    TAILQ_NEXT(found, q)->snap_min : WT_TXN_NONE;
+		    TAILQ_NEXT(found, q)->pinned_id : WT_TXN_NONE;
+		WT_DIAGNOSTIC_YIELD;
+		WT_ASSERT(session, txn_global->nsnap_oldest_id == WT_TXN_NONE ||
+		    !__wt_txn_visible_all(
+		    session, txn_global->nsnap_oldest_id));
+	}
 	TAILQ_REMOVE(&txn_global->nsnaph, found, q);
 	__nsnap_destroy(session, found);
 	WT_STAT_CONN_INCR(session, txn_snapshots_dropped);
@@ -104,7 +111,7 @@ __nsnap_drop_to(WT_SESSION_IMPL *session, WT_CONFIG_ITEM *name, bool inclusive)
 		}
 
 		if (TAILQ_NEXT(last, q) != NULL)
-			new_nsnap_oldest = TAILQ_NEXT(last, q)->snap_min;
+			new_nsnap_oldest = TAILQ_NEXT(last, q)->pinned_id;
 	}
 
 	do {
@@ -117,7 +124,15 @@ __nsnap_drop_to(WT_SESSION_IMPL *session, WT_CONFIG_ITEM *name, bool inclusive)
 	} while (nsnap != last && !TAILQ_EMPTY(&txn_global->nsnaph));
 
 	/* Now that the queue of named snapshots is updated, update the ID */
+	WT_ASSERT(session, !__wt_txn_visible_all(
+	    session, txn_global->nsnap_oldest_id) &&
+	    (new_nsnap_oldest == WT_TXN_NONE ||
+	    WT_TXNID_LE(txn_global->nsnap_oldest_id, new_nsnap_oldest)));
 	txn_global->nsnap_oldest_id = new_nsnap_oldest;
+	WT_DIAGNOSTIC_YIELD;
+	WT_ASSERT(session,
+	    new_nsnap_oldest == WT_TXN_NONE ||
+	    !__wt_txn_visible_all(session, new_nsnap_oldest));
 
 	return (ret);
 }
@@ -157,6 +172,7 @@ __wt_txn_named_snapshot_begin(WT_SESSION_IMPL *session, const char *cfg[])
 	WT_ERR(__wt_calloc_one(session, &nsnap_new));
 	nsnap = nsnap_new;
 	WT_ERR(__wt_strndup(session, cval.str, cval.len, &nsnap->name));
+	nsnap->pinned_id = WT_SESSION_TXN_STATE(session)->pinned_id;
 	nsnap->snap_min = txn->snap_min;
 	nsnap->snap_max = txn->snap_max;
 	if (txn->snapshot_count > 0) {
@@ -175,15 +191,25 @@ __wt_txn_named_snapshot_begin(WT_SESSION_IMPL *session, const char *cfg[])
 	 */
 	WT_ERR_NOTFOUND_OK(__nsnap_drop_one(session, &cval));
 
-	if (TAILQ_EMPTY(&txn_global->nsnaph))
-		txn_global->nsnap_oldest_id = nsnap_new->snap_min;
+	if (TAILQ_EMPTY(&txn_global->nsnaph)) {
+		WT_ASSERT(session, txn_global->nsnap_oldest_id == WT_TXN_NONE &&
+		    !__wt_txn_visible_all(session, nsnap_new->pinned_id));
+		__wt_readlock(session, txn_global->scan_rwlock);
+		txn_global->nsnap_oldest_id = nsnap_new->pinned_id;
+		__wt_readunlock(session, txn_global->scan_rwlock);
+	}
 	TAILQ_INSERT_TAIL(&txn_global->nsnaph, nsnap_new, q);
 	WT_STAT_CONN_INCR(session, txn_snapshots_created);
 	nsnap_new = NULL;
 
-err:	if (started_txn)
+err:	if (started_txn) {
+#ifdef HAVE_DIAGNOSTIC
+		uint64_t pinned_id = WT_SESSION_TXN_STATE(session)->pinned_id;
+#endif
 		WT_TRET(__wt_txn_rollback(session, NULL));
-	else if (ret == 0)
+		WT_DIAGNOSTIC_YIELD;
+		WT_ASSERT(session, !__wt_txn_visible_all(session, pinned_id));
+	} else if (ret == 0)
 		F_SET(txn, WT_TXN_NAMED_SNAPSHOT);
 
 	if (nsnap_new != NULL)
@@ -258,7 +284,20 @@ __wt_txn_named_snapshot_get(WT_SESSION_IMPL *session, WT_CONFIG_ITEM *nameval)
 	__wt_readlock(session, txn_global->nsnap_rwlock);
 	TAILQ_FOREACH(nsnap, &txn_global->nsnaph, q)
 		if (WT_STRING_MATCH(nsnap->name, nameval->str, nameval->len)) {
-			txn->snap_min = txn_state->snap_min = nsnap->snap_min;
+			/*
+			 * Acquire the scan lock so the oldest ID can't move
+			 * forward without seeing our pinned ID.
+			 */
+			__wt_readlock(session, txn_global->scan_rwlock);
+			txn_state->pinned_id = nsnap->pinned_id;
+			__wt_readunlock(session, txn_global->scan_rwlock);
+
+			WT_ASSERT(session, !__wt_txn_visible_all(
+			    session, txn_state->pinned_id) &&
+			    txn_global->nsnap_oldest_id != WT_TXN_NONE &&
+			    WT_TXNID_LE(txn_global->nsnap_oldest_id,
+			    txn_state->pinned_id));
+			txn->snap_min = nsnap->snap_min;
 			txn->snap_max = nsnap->snap_max;
 			if ((txn->snapshot_count = nsnap->snapshot_count) != 0)
 				memcpy(txn->snapshot, nsnap->snapshot,
diff --git a/test/checkpoint/smoke.sh b/test/checkpoint/smoke.sh
index 2f1d4345ad7..123d4e00df5 100755
--- a/test/checkpoint/smoke.sh
+++ b/test/checkpoint/smoke.sh
@@ -6,6 +6,9 @@ set -e
 echo "checkpoint: 3 mixed tables"
 $TEST_WRAPPER ./t -T 3 -t m
 
+# We are done if short tests are requested
+test -z "$TESTUTIL_DISABLE_LONG_TESTS" || exit 0
+
 echo "checkpoint: 6 column-store tables"
 $TEST_WRAPPER ./t -T 6 -t c
 
diff --git a/test/csuite/wt2246_col_append/main.c b/test/csuite/wt2246_col_append/main.c
index b795816c76f..1da8732abb4 100644
--- a/test/csuite/wt2246_col_append/main.c
+++ b/test/csuite/wt2246_col_append/main.c
@@ -104,6 +104,8 @@ main(int argc, char *argv[])
 	char buf[100];
 
 	opts = &_opts;
+	if (testutil_disable_long_tests())
+		return (0);
 	memset(opts, 0, sizeof(*opts));
 	opts->table_type = TABLE_ROW;
 	opts->n_append_threads = N_APPEND_THREADS;
diff --git a/test/csuite/wt2323_join_visibility/main.c b/test/csuite/wt2323_join_visibility/main.c
index bbf1626fe82..5987b77fd7d 100644
--- a/test/csuite/wt2323_join_visibility/main.c
+++ b/test/csuite/wt2323_join_visibility/main.c
@@ -96,6 +96,8 @@ main(int argc, char *argv[])
 
 	opts = &_opts;
 	sharedopts = &_sharedopts;
+	if (testutil_disable_long_tests())
+		return (0);
 	memset(opts, 0, sizeof(*opts));
 	memset(sharedopts, 0, sizeof(*sharedopts));
 
@@ -225,7 +227,8 @@ test_join(TEST_OPTS *opts, SHARED_OPTS *sharedopts, bool bloom,
 	testutil_check(session->close(session, NULL));
 }
 
-static void *thread_insert(void *arg)
+static void *
+thread_insert(void *arg)
 {
 	SHARED_OPTS *sharedopts;
 	TEST_OPTS *opts;
@@ -239,7 +242,7 @@ static void *thread_insert(void *arg)
 	threadargs = (THREAD_ARGS *)arg;
 	opts = threadargs->testopts;
 	sharedopts = threadargs->sharedopts;
-	testutil_check(__wt_random_init_seed(NULL, &rnd));
+	__wt_random_init_seed(NULL, &rnd);
 
 	testutil_check(opts->conn->open_session(
 	    opts->conn, NULL, NULL, &session));
diff --git a/test/csuite/wt2535_insert_race/main.c b/test/csuite/wt2535_insert_race/main.c
index 5eaca3279b6..ee567df8749 100644
--- a/test/csuite/wt2535_insert_race/main.c
+++ b/test/csuite/wt2535_insert_race/main.c
@@ -52,6 +52,8 @@ main(int argc, char *argv[])
 	int i;
 
 	opts = &_opts;
+	if (testutil_disable_long_tests())
+		return (0);
 	memset(opts, 0, sizeof(*opts));
 	opts->nthreads = 10;
 	opts->nrecords = 1000;
diff --git a/test/csuite/wt2695_checksum/main.c b/test/csuite/wt2695_checksum/main.c
index afb9d0788bd..50f118bf828 100644
--- a/test/csuite/wt2695_checksum/main.c
+++ b/test/csuite/wt2695_checksum/main.c
@@ -61,7 +61,7 @@ main(int argc, char *argv[])
 	    wiredtiger_open(opts->home, NULL, "create", &opts->conn));
 
 	/* Initialize the RNG. */
-	testutil_check(__wt_random_init_seed(NULL, &rnd));
+	__wt_random_init_seed(NULL, &rnd);
 
 	/* Allocate aligned memory for the data. */
 	data = dcalloc(DATASIZE, sizeof(uint8_t));
diff --git a/test/csuite/wt2719_reconfig/main.c b/test/csuite/wt2719_reconfig/main.c
index b67dae6d647..64a47ea49a6 100644
--- a/test/csuite/wt2719_reconfig/main.c
+++ b/test/csuite/wt2719_reconfig/main.c
@@ -256,7 +256,7 @@ main(int argc, char *argv[])
 	    session, opts->uri, "type=lsm,key_format=S,value_format=S"));
 
 	/* Initialize the RNG. */
-	testutil_check(__wt_random_init_seed(NULL, &rnd));
+	__wt_random_init_seed(NULL, &rnd);
 
 	/* Allocate memory for the config. */
 	len = WT_ELEMENTS(list) * 64;
diff --git a/test/csuite/wt2834_join_bloom_fix/main.c b/test/csuite/wt2834_join_bloom_fix/main.c
index 1e2d919d3c7..1d6abcfb179 100644
--- a/test/csuite/wt2834_join_bloom_fix/main.c
+++ b/test/csuite/wt2834_join_bloom_fix/main.c
@@ -62,6 +62,8 @@ main(int argc, char *argv[])
 	char joinuri[256];
 
 	opts = &_opts;
+	if (testutil_disable_long_tests())
+		return (0);
 	memset(opts, 0, sizeof(*opts));
 
 	testutil_check(testutil_parse_opts(argc, argv, opts));
@@ -159,7 +161,8 @@ main(int argc, char *argv[])
 	return (0);
 }
 
-void populate(TEST_OPTS *opts)
+void
+populate(TEST_OPTS *opts)
 {
 	WT_CURSOR *maincur;
 	WT_SESSION *session;
@@ -167,7 +170,7 @@ void populate(TEST_OPTS *opts)
 	int balance, i, flag, post;
 	WT_RAND_STATE rnd;
 
-	testutil_check(__wt_random_init_seed(NULL, &rnd));
+	__wt_random_init_seed(NULL, &rnd);
 
 	testutil_check(opts->conn->open_session(
 	    opts->conn, NULL, NULL, &session));
diff --git a/test/csuite/wt2853_perf/main.c b/test/csuite/wt2853_perf/main.c
index 67ba4a20ada..27591fdf214 100644
--- a/test/csuite/wt2853_perf/main.c
+++ b/test/csuite/wt2853_perf/main.c
@@ -201,7 +201,7 @@ thread_insert(void *arg)
 
 	threadargs = (THREAD_ARGS *)arg;
 	opts = threadargs->testopts;
-	testutil_check(__wt_random_init_seed(NULL, &rnd));
+	__wt_random_init_seed(NULL, &rnd);
 	(void)time(&prevtime);
 
 	testutil_check(opts->conn->open_session(
diff --git a/test/format/lrt.c b/test/format/lrt.c
index 937525522fa..69d6b22d71f 100644
--- a/test/format/lrt.c
+++ b/test/format/lrt.c
@@ -96,6 +96,22 @@ lrt(void *arg)
 			pinned = 0;
 		} else {
 			/*
+			 * Test named snapshots: create a snapshot, wait to
+			 * give the transaction state time to move forward,
+			 * then start a transaction with the named snapshot,
+			 * drop it, then commit the transaction. This exercises
+			 * most of the named snapshot logic under load.
+			 */
+			testutil_check(session->snapshot(session, "name=test"));
+			sleep(1);
+			testutil_check(session->begin_transaction(
+			    session, "snapshot=test"));
+			testutil_check(session->snapshot(
+			    session, "drop=(all)"));
+			testutil_check(session->commit_transaction(
+			    session, NULL));
+
+			/*
 			 * Begin transaction: without an explicit transaction,
 			 * the snapshot is only kept around while a cursor is
 			 * positioned. As soon as the cursor loses its position
diff --git a/test/format/t.c b/test/format/t.c
index 12258af8e51..41bdea11e73 100644
--- a/test/format/t.c
+++ b/test/format/t.c
@@ -115,7 +115,7 @@ main(int argc, char *argv[])
 	argv += __wt_optind;
 
 	/* Initialize the global RNG. */
-	testutil_check(__wt_random_init_seed(NULL, &g.rnd));
+	__wt_random_init_seed(NULL, &g.rnd);
 
 	/* Set up paths. */
 	path_setup(home);
diff --git a/test/format/util.c b/test/format/util.c
index 667f6d6bcb1..a709aa93a2e 100644
--- a/test/format/util.c
+++ b/test/format/util.c
@@ -78,7 +78,7 @@ key_gen_setup(WT_ITEM *key)
 }
 
 static void
-key_gen_common(WT_ITEM *key, uint64_t keyno, int suffix)
+key_gen_common(WT_ITEM *key, uint64_t keyno, const char * const suffix)
 {
 	int len;
 	char *p;
@@ -86,11 +86,15 @@ key_gen_common(WT_ITEM *key, uint64_t keyno, int suffix)
 	p = key->mem;
 
 	/*
-	 * The key always starts with a 10-digit string (the specified cnt)
+	 * The key always starts with a 10-digit string (the specified row)
 	 * followed by two digits, a random number between 1 and 15 if it's
 	 * an insert, otherwise 00.
 	 */
-	len = sprintf(p, "%010" PRIu64 ".%02d", keyno, suffix);
+	u64_to_string_zf(keyno, key->mem, 11);
+	p[10] = '.';
+	p[11] = suffix[0];
+	p[12] = suffix[1];
+	len = 13;
 
 	/*
 	 * In a column-store, the key is only used for Berkeley DB inserts,
@@ -118,13 +122,19 @@ key_gen_common(WT_ITEM *key, uint64_t keyno, int suffix)
 void
 key_gen(WT_ITEM *key, uint64_t keyno)
 {
-	key_gen_common(key, keyno, 0);
+	key_gen_common(key, keyno, "00");
 }
 
 void
 key_gen_insert(WT_RAND_STATE *rnd, WT_ITEM *key, uint64_t keyno)
 {
-	key_gen_common(key, keyno, (int)mmrand(rnd, 1, 15));
+	static const char * const suffix[15] = {
+	    "01", "02", "03", "04", "05",
+	    "06", "07", "08", "09", "10",
+	    "11", "12", "13", "14", "15"
+	};
+
+	key_gen_common(key, keyno, suffix[mmrand(rnd, 1, 15) - 1]);
 }
 
 static uint32_t val_dup_data_len;	/* Length of duplicate data items */
@@ -221,7 +231,7 @@ val_gen(WT_RAND_STATE *rnd, WT_ITEM *value, uint64_t keyno)
 		p[10] = '/';
 		value->size = val_dup_data_len;
 	} else {
-		(void)sprintf(p, "%010" PRIu64, keyno);
+		u64_to_string_zf(keyno, p, 11);
 		p[10] = '/';
 		value->size =
 		    value_len(rnd, keyno, g.c_value_min, g.c_value_max);
diff --git a/test/format/wts.c b/test/format/wts.c
index 74c4bb902b3..1600786855a 100644
--- a/test/format/wts.c
+++ b/test/format/wts.c
@@ -546,6 +546,7 @@ wts_stats(void)
 	WT_DECL_RET;
 	WT_SESSION *session;
 	FILE *fp;
+	size_t len;
 	char *stat_name;
 	const char *pval, *desc;
 	uint64_t v;
@@ -582,8 +583,9 @@ wts_stats(void)
 
 	/* Data source statistics. */
 	fprintf(fp, "\n\n====== Data source statistics:\n");
-	stat_name = dmalloc(strlen("statistics:") + strlen(g.uri) + 1);
-	sprintf(stat_name, "statistics:%s", g.uri);
+	len = strlen("statistics:") + strlen(g.uri) + 1;
+	stat_name = dmalloc(len);
+	snprintf(stat_name, len, "statistics:%s", g.uri);
 	testutil_check(session->open_cursor(
 	    session, stat_name, NULL, NULL, &cursor));
 	free(stat_name);
diff --git a/test/java/com/wiredtiger/test/ConcurrentCloseTest.java b/test/java/com/wiredtiger/test/ConcurrentCloseTest.java
index fece0353bf0..fead0b0bf38 100644
--- a/test/java/com/wiredtiger/test/ConcurrentCloseTest.java
+++ b/test/java/com/wiredtiger/test/ConcurrentCloseTest.java
@@ -34,6 +34,7 @@ import com.wiredtiger.db.WiredTigerException;
 import com.wiredtiger.db.wiredtiger;
 
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.fail;
 
 import java.io.BufferedReader;
 import java.io.File;
@@ -69,7 +70,7 @@ class InsertThread extends Thread {
                 Session session = conn.open_session(null);
                 Cursor cursor = session.open_cursor("table:cclose", null,
                                                     "overwrite");
-                cursor.putKeyString("key"+threadId + "-" + i);
+                cursor.putKeyString("key" + threadId + "-" + i);
                 cursor.putValueString("value1");
                 ret = cursor.insert();
                 cursor.close();
@@ -127,36 +128,36 @@ public class ConcurrentCloseTest {
         setup();
         try {
             List<Thread> threads = new ArrayList<Thread>();
-            int i, ret;
+            int i;
 
-            ret = session.create("table:cclose", "key_format=S,value_format=S");
+            assertEquals(0, session.create("table:cclose",
+                                           "key_format=S,value_format=S"));
             Cursor cursor = session.open_cursor("table:cclose", null,
                                                 "overwrite");
             cursor.putKeyString("key1");
             cursor.putValueString("value1");
-            ret = cursor.insert();
+            assertEquals(0, cursor.insert());
             cursor.close();
-            ret = session.close(null);
+            assertEquals(0, session.close(null));
 
             for (i = 0; i < NUM_THREADS; i++) {
                 Thread insertThread = new InsertThread(conn, i);
-                Thread scanThread = new InsertThread(conn, i);
+                Thread scanThread = new ScanThread(conn);
                 insertThread.start();
                 scanThread.start();
                 threads.add(insertThread);
                 threads.add(scanThread);
             }
-
             for (Thread thread : threads)
                 try {
                     thread.join();
-                    ret = -1;
                 }
                 catch (InterruptedException ie) {
+                    fail();
                 }
 
-            ret = conn.close(null);
-            System.exit(ret);
+            assertEquals(0, conn.close(null));
+            System.exit(0);
         }
         catch (WiredTigerException wte) {
             System.err.println("Exception: " + wte);
diff --git a/test/recovery/random-abort.c b/test/recovery/random-abort.c
index 16065cec29e..22a163bedff 100644
--- a/test/recovery/random-abort.c
+++ b/test/recovery/random-abort.c
@@ -245,7 +245,7 @@ main(int argc, char *argv[])
 	if (!verify_only) {
 		testutil_make_work_dir(home);
 
-		testutil_assert(__wt_random_init_seed(NULL, &rnd) == 0);
+		__wt_random_init_seed(NULL, &rnd);
 		if (rand_time) {
 			timeout = __wt_random(&rnd) % MAX_TIME;
 			if (timeout < MIN_TIME)
diff --git a/test/suite/test_inmem02.py b/test/suite/test_inmem02.py
new file mode 100644
index 00000000000..9eb8330b2a3
--- /dev/null
+++ b/test/suite/test_inmem02.py
@@ -0,0 +1,64 @@
+#!/usr/bin/env python
+#
+# Public Domain 2014-2016 MongoDB, Inc.
+# Public Domain 2008-2014 WiredTiger, Inc.
+#
+# This is free and unencumbered software released into the public domain.
+#
+# Anyone is free to copy, modify, publish, use, compile, sell, or
+# distribute this software, either in source code form or as a compiled
+# binary, for any purpose, commercial or non-commercial, and by any
+# means.
+#
+# In jurisdictions that recognize copyright laws, the author or authors
+# of this software dedicate any and all copyright interest in the
+# software to the public domain. We make this dedication for the benefit
+# of the public at large and to the detriment of our heirs and
+# successors. We intend this dedication to be an overt act of
+# relinquishment in perpetuity of all present and future rights to this
+# software under copyright law.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+# IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR
+# OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+# ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+# OTHER DEALINGS IN THE SOFTWARE.
+
+import wiredtiger, wttest
+from time import sleep
+from helper import simple_populate, simple_populate_check
+from helper import key_populate, value_populate
+from wtscenario import make_scenarios
+
+# test_inmem02.py
+#    Test in-memory with ignore-cache-size setting.
+class test_inmem02(wttest.WiredTigerTestCase):
+    uri = 'table:inmem02'
+    conn_config = \
+        'cache_size=3MB,file_manager=(close_idle_time=0),in_memory=true'
+    table_config = 'key_format=S,value_format=S,memory_page_max=32k,leaf_page_max=4k'
+
+    # Add more data than fits into the configured cache and verify it fails.
+    def test_insert_over_allowed(self):
+
+        # Create a new table that is allowed to exceed the cache size, do this
+        # before filling the cache so that the create succeeds
+        self.session.create(
+            self.uri + '_over', 'ignore_in_memory_cache_size=true')
+
+        # Populate a table with enough data to fill the cache.
+        msg = '/WT_CACHE_FULL.*/'
+        self.assertRaisesHavingMessage(wiredtiger.WiredTigerError,
+            lambda:simple_populate(
+            self, self.uri, self.table_config, 10000000), msg)
+
+        # Add some content to the new table
+        cursor = self.session.open_cursor(self.uri + '_over', None)
+        for i in range(1, 1000):
+            cursor[str('%015d' % i)] = str(i) + ': abcdefghijklmnopqrstuvwxyz'
+        cursor.close()
+
+if __name__ == '__main__':
+    wttest.run()
diff --git a/test/utility/test_util.h b/test/utility/test_util.h
index 3c1d0e2630a..1047d1ca8a0 100644
--- a/test/utility/test_util.h
+++ b/test/utility/test_util.h
@@ -108,6 +108,62 @@ typedef struct {
 		    __func__, __LINE__, #call, __VA_ARGS__);		\
 } while (0)
 
+/*
+ * u64_to_string --
+ *	Convert a uint64_t to a text string.
+ *
+ * Algorithm from Andrei Alexandrescu's talk: "Three Optimization Tips for C++"
+ */
+static inline void
+u64_to_string(uint64_t n, char **pp)
+{
+	static const char hundred_lookup[201] =
+	    "0001020304050607080910111213141516171819"
+	    "2021222324252627282930313233343536373839"
+	    "4041424344454647484950515253545556575859"
+	    "6061626364656667686970717273747576777879"
+	    "8081828384858687888990919293949596979899";
+	u_int i;
+	char *p;
+
+	/*
+	 * The argument pointer references the last element of a buffer (which
+	 * must be large enough to hold any possible value).
+	 *
+	 * Nul-terminate the buffer.
+	 */
+	for (p = *pp, *p-- = '\0'; n >= 100; n /= 100) {
+		i = (n % 100) * 2;
+		*p-- = hundred_lookup[i + 1];
+		*p-- = hundred_lookup[i];
+	}
+
+	/* Handle the last two digits. */
+	i = (u_int)n * 2;
+	*p = hundred_lookup[i + 1];
+	if (n >= 10)
+		*--p = hundred_lookup[i];
+
+	/* Return a pointer to the first byte of the text string. */
+	*pp = p;
+}
+
+/*
+ * u64_to_string_zf --
+ *	Convert a uint64_t to a text string, zero-filling the buffer.
+ */
+static inline void
+u64_to_string_zf(uint64_t n, char *buf, size_t len)
+{
+	char *p;
+
+	p = buf + (len - 1);
+	u64_to_string(n, &p);
+
+	while (p > buf)
+		*--p = '0';
+}
+
 /* Allow tests to add their own death handling. */
 extern void (*custom_die)(void);