Merge branch 'config-parse-api' into wtperf-multiple-databases

Conflicts:
	bench/wtperf/wtperf.c
	bench/wtperf/wtperf.h

35 files changed, 623 insertions, 538 deletions

diff --git a/bench/wtperf/config.c b/bench/wtperf/config.c
index 63944f802bc..800c760f72d 100644
--- a/bench/wtperf/config.c
+++ b/bench/wtperf/config.c
@@ -69,8 +69,8 @@ config_assign(CONFIG *dest, const CONFIG *src)
 	dest->popthreads = NULL;
 	dest->workers = NULL;
 
-	if (src->uri != NULL)
-		dest->uri = strdup(src->uri);
+	if (src->base_uri != NULL)
+		dest->base_uri = strdup(src->base_uri);
 	if (src->workload != NULL) {
 		dest->workload = calloc(WORKLOAD_MAX, sizeof(WORKLOAD));
 		memcpy(dest->workload,
@@ -121,7 +121,7 @@ config_free(CONFIG *cfg)
 
 	free(cfg->ckptthreads);
 	free(cfg->popthreads);
-	free(cfg->uri);
+	free(cfg->base_uri);
 	free(cfg->workers);
 	free(cfg->workload);
 }
@@ -168,9 +168,10 @@ config_threads(CONFIG *cfg, const char *config, size_t len)
 {
 	WORKLOAD *workp;
 	WT_CONFIG_ITEM groupk, groupv, k, v;
-	WT_CONFIG_SCAN *group, *scan;
+	WT_CONFIG_PARSER *group, *scan;
 	int ret;
 
+	group = scan = NULL;
 	/* Allocate the workload array. */
 	if ((cfg->workload = calloc(WORKLOAD_MAX, sizeof(WORKLOAD))) == NULL)
 		return (enomem(cfg));
@@ -185,11 +186,10 @@ config_threads(CONFIG *cfg, const char *config, size_t len)
 	 * returned from the original string.
 	 */
 	if ((ret =
-	    wiredtiger_config_scan_begin(NULL, config, len, &group)) != 0)
+	    wiredtiger_config_parser_open(NULL, config, len, &group)) != 0)
 		goto err;
-	while ((ret =
-	    wiredtiger_config_scan_next(NULL, group, &groupk, &groupv)) == 0) {
-		if ((ret = wiredtiger_config_scan_begin(
+	while ((ret = group->next(group, &groupk, &groupv)) == 0) {
+		if ((ret = wiredtiger_config_parser_open(
 		    NULL, groupk.str, groupk.len, &scan)) != 0)
 			goto err;
 		
@@ -203,8 +203,7 @@ config_threads(CONFIG *cfg, const char *config, size_t len)
 		}
 		workp = &cfg->workload[cfg->workload_cnt++];
 
-		while ((ret =
-		    wiredtiger_config_scan_next(NULL, scan, &k, &v)) == 0) {
+		while ((ret = scan->next(scan, &k, &v)) == 0) {
 			if (STRING_MATCH("count", k.str, k.len)) {
 				if ((workp->threads = v.val) <= 0)
 					goto err;
@@ -234,8 +233,10 @@ config_threads(CONFIG *cfg, const char *config, size_t len)
 			ret = 0;
 		if (ret != 0 )
 			goto err;
-		if ((ret = wiredtiger_config_scan_end(NULL, scan)) != 0)
+		if ((ret = scan->close(scan)) != 0) {
+			scan = NULL;
 			goto err;
+		}
 
 		if (workp->insert == 0 &&
 		    workp->read == 0 && workp->update == 0)
@@ -243,12 +244,19 @@ config_threads(CONFIG *cfg, const char *config, size_t len)
 		cfg->workers_cnt += (u_int)workp->threads;
 	}
 
-	if ((ret = wiredtiger_config_scan_end(NULL, group)) != 0)
+	if ((ret = group->close(group)) != 0) {
+		group = NULL;
 		goto err;
+	}
 
 	return (0);
 
-err:	fprintf(stderr,
+err:	if (group != NULL)
+		(void)group->close(group);
+	if (scan != NULL)
+		(void)scan->close(scan);
+		
+	fprintf(stderr,
 	    "invalid thread configuration or scan error: %.*s\n",
 	    (int)len, config);
 	return (EINVAL);
@@ -461,19 +469,17 @@ int
 config_opt_line(CONFIG *cfg, const char *optstr)
 {
 	WT_CONFIG_ITEM k, v;
-	WT_CONFIG_SCAN *scan;
+	WT_CONFIG_PARSER *scan;
 	int ret, t_ret;
 
-
-	if ((ret = wiredtiger_config_scan_begin(
+	if ((ret = wiredtiger_config_parser_open(
 	    NULL, optstr, strlen(optstr), &scan)) != 0) {
 		lprintf(cfg, ret, 0, "Error in config_scan_begin");
 		return (ret);
 	}
 
 	while (ret == 0) {
-		if ((ret =
-		    wiredtiger_config_scan_next(NULL, scan, &k, &v)) != 0) {
+		if ((ret = scan->next(scan, &k, &v)) != 0) {
 			/* Any parse error has already been reported. */
 			if (ret == WT_NOTFOUND)
 				ret = 0;
@@ -481,7 +487,7 @@ config_opt_line(CONFIG *cfg, const char *optstr)
 		}
 		ret = config_opt(cfg, &k, &v);
 	}
-	if ((t_ret = wiredtiger_config_scan_end(NULL, scan)) != 0) {
+	if ((t_ret = scan->close(scan)) != 0) {
 		lprintf(cfg, ret, 0, "Error in config_scan_end");
 		if (ret == 0)
 			ret = t_ret;
diff --git a/bench/wtperf/runners/test1-500m-lsm.wtperf b/bench/wtperf/runners/test1-500m-lsm.wtperf
index 0e79bdddb12..7f85b8c13e5 100644
--- a/bench/wtperf/runners/test1-500m-lsm.wtperf
+++ b/bench/wtperf/runners/test1-500m-lsm.wtperf
@@ -5,8 +5,9 @@
 #conn_config="cache_size=21G,checkpoint_sync=false,mmap=false,session_max=1024,statistics=(fast,clear),statistics_log=(wait=60)"
 conn_config="cache_size=21G,checkpoint_sync=false,mmap=false,session_max=1024"
 compact=true
+compression="snappy"
 sess_config="isolation=snapshot"
-table_config="internal_page_max=128K,lsm=(bloom_config=(leaf_page_max=8MB),bloom_bit_count=28,bloom_hash_count=19,bloom_oldest=true,chunk_max=100GB,chunk_size=100MB,merge_threads=3),type=lsm,leaf_page_max=16K"
+table_config="internal_page_max=128K,lsm=(bloom_config=(leaf_page_max=8MB),bloom_bit_count=28,bloom_hash_count=19,bloom_oldest=true,chunk_max=5GB,chunk_size=100MB,merge_threads=3),type=lsm,leaf_page_max=16K"
 icount=500000000
 key_sz=40
 value_sz=1000
diff --git a/bench/wtperf/runners/test2-500m-lsm.wtperf b/bench/wtperf/runners/test2-500m-lsm.wtperf
index f305ad621d0..db1ee9d469c 100644
--- a/bench/wtperf/runners/test2-500m-lsm.wtperf
+++ b/bench/wtperf/runners/test2-500m-lsm.wtperf
@@ -6,8 +6,9 @@
 #conn_config="cache_size=21G,checkpoint_sync=false,mmap=false,session_max=1024,statistics=(fast,clear),statistics_log=(wait=60)"
 conn_config="cache_size=21G,checkpoint_sync=false,mmap=false,session_max=1024"
 create=false
-sess_config="isolation=snapshot"
-table_config="internal_page_max=128K,lsm=(bloom_config=(leaf_page_max=8MB),bloom_bit_count=28,bloom_hash_count=19,bloom_oldest=true,chunk_max=100GB,chunk_size=100MB,merge_threads=3),type=lsm,leaf_page_max=16K"
+compression="snappy"
+sess_config="isolation=snapshot
+table_config="internal_page_max=128K,lsm=(bloom_config=(leaf_page_max=8MB),bloom_bit_count=28,bloom_hash_count=19,bloom_oldest=true,chunk_max=5GB,chunk_size=100MB,merge_threads=3),type=lsm,leaf_page_max=16K"
 key_sz=40
 value_sz=1000
 report_interval=10
diff --git a/bench/wtperf/runners/test3-500m-lsm.wtperf b/bench/wtperf/runners/test3-500m-lsm.wtperf
index 4960d52b869..446309c32c8 100644
--- a/bench/wtperf/runners/test3-500m-lsm.wtperf
+++ b/bench/wtperf/runners/test3-500m-lsm.wtperf
@@ -6,8 +6,9 @@
 #conn_config="cache_size=21G,checkpoint_sync=false,mmap=false,session_max=1024,statistics=(fast,clear),statistics_log=(wait=60)"
 conn_config="cache_size=21G,checkpoint_sync=false,mmap=false,session_max=1024"
 create=false
+compression="snappy"
 sess_config="isolation=snapshot"
-table_config="internal_page_max=128K,lsm=(bloom_config=(leaf_page_max=8MB),bloom_bit_count=28,bloom_hash_count=19,bloom_oldest=true,chunk_max=100GB,chunk_size=100MB,merge_threads=3),type=lsm,leaf_page_max=16K"
+table_config="internal_page_max=128K,lsm=(bloom_config=(leaf_page_max=8MB),bloom_bit_count=28,bloom_hash_count=19,bloom_oldest=true,chunk_max=5GB,chunk_size=100MB,merge_threads=3),type=lsm,leaf_page_max=16K"
 key_sz=40
 value_sz=1000
 pareto=true
diff --git a/bench/wtperf/runners/test4-500m-lsm.wtperf b/bench/wtperf/runners/test4-500m-lsm.wtperf
index 624241bb934..a959ec9057e 100644
--- a/bench/wtperf/runners/test4-500m-lsm.wtperf
+++ b/bench/wtperf/runners/test4-500m-lsm.wtperf
@@ -6,8 +6,9 @@
 #conn_config="cache_size=21G,checkpoint_sync=false,mmap=false,session_max=1024,statistics=(fast,clear),statistics_log=(wait=60)"
 conn_config="cache_size=21G,checkpoint_sync=false,mmap=false,session_max=1024"
 create=false
+compression="snappy"
 sess_config="isolation=snapshot"
-table_config="internal_page_max=128K,lsm=(bloom_config=(leaf_page_max=8MB),bloom_bit_count=28,bloom_hash_count=19,bloom_oldest=true,chunk_max=100GB,chunk_size=100MB,merge_threads=3),type=lsm,leaf_page_max=16K"
+table_config="internal_page_max=128K,lsm=(bloom_config=(leaf_page_max=8MB),bloom_bit_count=28,bloom_hash_count=19,bloom_oldest=true,chunk_max=5GB,chunk_size=100MB,merge_threads=3),type=lsm,leaf_page_max=16K"
 key_sz=40
 value_sz=1000
 report_interval=10
diff --git a/bench/wtperf/wtperf.c b/bench/wtperf/wtperf.c
index 94afcf01e85..df78bca021f 100644
--- a/bench/wtperf/wtperf.c
+++ b/bench/wtperf/wtperf.c
@@ -31,7 +31,7 @@
 static const CONFIG default_cfg = {
 	"WT_TEST",			/* home */
 	"WT_TEST",			/* monitor dir */
-	NULL,				/* uri */
+	NULL,				/* base_uri */
 	NULL,				/* uris */
 	NULL,				/* helium_mount */
 	NULL,				/* conn */
@@ -212,28 +212,21 @@ worker(void *arg)
 		lprintf(cfg, ret, 0, "worker: WT_CONNECTION.open_session");
 		goto err;
 	}
-	if (cfg->table_count > 1) {
-		cursors = (WT_CURSOR **)calloc(
-		    cfg->table_count, sizeof(WT_CURSOR *));
-		if (cursors == NULL) {
-			lprintf(cfg, ENOMEM, 0,
-			    "worker: couldn't allocate cursor array");
+	cursors = (WT_CURSOR **)calloc(
+	    cfg->table_count, sizeof(WT_CURSOR *));
+	if (cursors == NULL) {
+		lprintf(cfg, ENOMEM, 0,
+		    "worker: couldn't allocate cursor array");
+		goto err;
+	}
+	for (i = 0; i < cfg->table_count; i++) {
+		if ((ret = session->open_cursor(session,
+		    cfg->uris[i], NULL, NULL, &cursors[i])) != 0) {
+			lprintf(cfg, ret, 0,
+			    "worker: WT_SESSION.open_cursor: %s",
+			    cfg->uris[i]);
 			goto err;
 		}
-		for (i = 0; i < cfg->table_count; i++) {
-			if ((ret = session->open_cursor(session,
-			    cfg->uris[i], NULL, NULL, &cursors[i])) != 0) {
-				lprintf(cfg, ret, 0,
-				    "worker: WT_SESSION.open_cursor: %s",
-				    cfg->uris[i]);
-				goto err;
-			}
-		}
-	} else if ((ret = session->open_cursor(
-	    session, cfg->uri, NULL, NULL, &cursor)) != 0) {
-		lprintf(cfg,
-		    ret, 0, "worker: WT_SESSION.open_cursor: %s", cfg->uri);
-		goto err;
 	}
 
 	key_buf = thread->key_buf;
@@ -243,11 +236,6 @@ worker(void *arg)
 	op_end = op + sizeof(thread->workload->ops);
 
 	while (!cfg->stop) {
-		/* Pick a cursor if there are multiple tables. */
-		if (cfg->table_count > 1)
-			cursor = cursors[
-			    __wt_random() % (cfg->table_count - 1)];
-
 		/*
 		 * Generate the next key and setup operation specific
 		 * statistics tracking objects.
@@ -282,7 +270,18 @@ worker(void *arg)
 		}
 
 		sprintf(key_buf, "%0*" PRIu64, cfg->key_sz, next_val);
-		measure_latency = cfg->sample_interval != 0 && (
+
+		/*
+		 * Spread the data out around the multiple databases.
+		 */
+		cursor = cursors[next_val % cfg->table_count];
+
+		/*
+		 * 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->ops != 0 && (
 		    trk->ops % cfg->sample_rate == 0);
 		if (measure_latency &&
 		    (ret = __wt_epoch(NULL, &start)) != 0) {
@@ -529,30 +528,23 @@ populate_thread(void *arg)
 
 	/* Do bulk loads if populate is single-threaded. */
 	cursor_config = cfg->populate_threads == 1 ? "bulk" : NULL;
-	/* Create the cursor or cursors if there are multiple tables. */
-	if (cfg->table_count > 1) {
-		cursors = (WT_CURSOR **)calloc(
-		    cfg->table_count, sizeof(WT_CURSOR *));
-		if (cursors == NULL) {
-			lprintf(cfg, ENOMEM, 0,
-			    "worker: couldn't allocate cursor array");
+	/* Create the cursors. */
+	cursors = (WT_CURSOR **)calloc(
+	    cfg->table_count, sizeof(WT_CURSOR *));
+	if (cursors == NULL) {
+		lprintf(cfg, ENOMEM, 0,
+		    "worker: couldn't allocate cursor array");
+		goto err;
+	}
+	for (i = 0; i < cfg->table_count; i++) {
+		if ((ret = session->open_cursor(
+		    session, cfg->uris[i], NULL,
+		    cursor_config, &cursors[i])) != 0) {
+			lprintf(cfg, ret, 0,
+			    "populate: WT_SESSION.open_cursor: %s",
+			    cfg->uris[i]);
 			goto err;
 		}
-		for (i = 0; i < cfg->table_count; i++) {
-			if ((ret = session->open_cursor(
-			    session, cfg->uris[i], NULL,
-			    cursor_config, &cursors[i])) != 0) {
-				lprintf(cfg, ret, 0,
-				    "populate: WT_SESSION.open_cursor: %s",
-				    cfg->uris[i]);
-				goto err;
-			}
-		}
-	} else if ((ret = session->open_cursor(
-	    session, cfg->uri, NULL, cursor_config, &cursor)) != 0) {
-		lprintf(cfg,
-		    ret, 0, "populate: WT_SESSION.open_cursor: %s", cfg->uri);
-		goto err;
 	}
 
 	/* Populate the databases. */
@@ -570,38 +562,44 @@ populate_thread(void *arg)
 			}
 			intxn = 1;
 		}
+		/*
+		 * Figure out which table this op belongs to.
+		 */
+		cursor = cursors[op % cfg->table_count];
 		sprintf(key_buf, "%0*" PRIu64, cfg->key_sz, op);
-		measure_latency = cfg->sample_interval != 0 && (
+		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;
 		}
-		for (i = 0; i < cfg->table_count; i++) {
-			if (cfg->table_count > 1)
-				cursor = cursors[i];
-			cursor->set_key(cursor, key_buf);
-			if (cfg->random_value)
-				randomize_value(cfg, value_buf);
-			cursor->set_value(cursor, value_buf);
-			if ((ret = cursor->insert(cursor)) != 0) {
-				lprintf(cfg, ret, 0, "Failed inserting");
+		cursor->set_key(cursor, key_buf);
+		if (cfg->random_value)
+			randomize_value(cfg, value_buf);
+		cursor->set_value(cursor, value_buf);
+		if ((ret = cursor->insert(cursor)) != 0) {
+			lprintf(cfg, ret, 0, "Failed inserting");
+			goto err;
+		}
+		/*
+		 * Gather statistics.
+		 * We measure the latency of inserting a single key.  If there
+		 * are multiple tables, it is the time for insertion into all
+		 * of them.
+		 */
+		if (measure_latency) {
+			if ((ret = __wt_epoch(NULL, &stop)) != 0) {
+				lprintf(cfg, ret, 0,
+				    "Get time call failed");
 				goto err;
 			}
-			/* Gather statistics */
-			if (measure_latency) {
-				if ((ret = __wt_epoch(NULL, &stop)) != 0) {
-					lprintf(cfg, ret, 0,
-					    "Get time call failed");
-					goto err;
-				}
-				++trk->latency_ops;
-				usecs = ns_to_us(WT_TIMEDIFF(stop, start));
-				track_operation(trk, usecs);
-			}
-			++thread->insert.ops;	/* Same as trk->ops */
+			++trk->latency_ops;
+			usecs = ns_to_us(WT_TIMEDIFF(stop, start));
+			track_operation(trk, usecs);
 		}
+		++thread->insert.ops;	/* Same as trk->ops */
 
 		if (cfg->populate_ops_per_txn != 0) {
 			if (++opcount < cfg->populate_ops_per_txn)
@@ -833,6 +831,7 @@ execute_populate(CONFIG *cfg)
 	WT_SESSION *session;
 	struct timespec start, stop;
 	double secs;
+	size_t i;
 	uint64_t last_ops;
 	uint32_t interval;
 	int elapsed, ret, t_ret;
@@ -927,12 +926,17 @@ execute_populate(CONFIG *cfg)
 			lprintf(cfg, ret, 0, "Get time failed in populate.");
 			goto err;
 		}
-		if ((ret = session->compact(
-		    session, cfg->uri, "timeout=0")) != 0) {
-			lprintf(cfg, ret, 0,
-			     "execute_populate: WT_SESSION.compact");
-			goto err;
-		}
+		/*
+		 * We measure how long it takes to compact all tables for this
+		 * workload.
+		 */
+		for (i = 0; i < cfg->table_count; i++)
+			if ((ret = session->compact(
+			    session, cfg->uris[i], "timeout=0")) != 0) {
+				lprintf(cfg, ret, 0,
+				     "execute_populate: WT_SESSION.compact");
+				goto err;
+			}
 		if ((ret = __wt_epoch(NULL, &stop)) != 0) {
 			lprintf(cfg, ret, 0, "Get time failed in populate.");
 			goto err;
@@ -1085,47 +1089,54 @@ find_table_count(CONFIG *cfg)
 	WT_CURSOR *cursor;
 	WT_SESSION *session;
 	char *key;
+	uint32_t i, max_icount, table_icount;
 	int ret, t_ret;
 
 	conn = cfg->conn;
 
+	max_icount = 0;
 	if ((ret = conn->open_session(
 	    conn, NULL, cfg->sess_config, &session)) != 0) {
 		lprintf(cfg, ret, 0,
-		    "open_session failed finding existing table count");
-		goto err;
-	}
-	if ((ret = session->open_cursor(session, cfg->uri,
-	    NULL, NULL, &cursor)) != 0) {
-		lprintf(cfg, ret, 0,
-		    "open_cursor failed finding existing table count");
-		goto err;
-	}
-	if ((ret = cursor->prev(cursor)) != 0) {
-		lprintf(cfg, ret, 0,
-		    "cursor prev failed finding existing table count");
-		goto err;
-	}
-	if ((ret = cursor->get_key(cursor, &key)) != 0) {
-		lprintf(cfg, ret, 0,
-		    "cursor get_key failed finding existing table count");
-		goto err;
+		    "find_table_count: open_session failed");
+		goto out;
 	}
-	cfg->icount = (uint32_t)atoi(key);
+	for (i = 0; i < cfg->table_count; i++) {
+		if ((ret = session->open_cursor(session, cfg->uris[i],
+		    NULL, NULL, &cursor)) != 0) {
+			lprintf(cfg, ret, 0,
+			    "find_table_count: open_cursor failed");
+			goto err;
+		}
+		if ((ret = cursor->prev(cursor)) != 0) {
+			lprintf(cfg, ret, 0,
+			    "find_table_count: cursor prev failed");
+			goto err;
+		}
+		if ((ret = cursor->get_key(cursor, &key)) != 0) {
+			lprintf(cfg, ret, 0,
+			    "find_table_count: cursor get_key failed");
+			goto err;
+		}
+		table_icount = (uint32_t)atoi(key);
+		if (table_icount > max_icount)
+			max_icount = table_icount;
 
-err:	if ((t_ret = session->close(session, NULL)) != 0) {
-		if (ret == 0)
-			ret = t_ret;
-		lprintf(cfg, ret, 0,
-		    "session close failed finding existing table count");
+err:		if ((t_ret = session->close(session, NULL)) != 0) {
+			if (ret == 0)
+				ret = t_ret;
+			lprintf(cfg, ret, 0,
+			    "find_table_count: session close failed");
+		}
 	}
-	return (ret);
+	cfg->icount = max_icount;
+out:	return (ret);
 }
 
 /*
  * Populate the uri array if more than one table is being used.
  */
-int
+static int
 create_uris(CONFIG *cfg)
 {
 	char *uri;
@@ -1134,12 +1145,7 @@ create_uris(CONFIG *cfg)
 	uint32_t i;
 
 	ret = 0;
-	if (cfg->table_count < 2) {
-		cfg->uris = NULL;
-		return (0);
-	}
-
-	base_uri_len = strlen(cfg->uri);
+	base_uri_len = strlen(cfg->base_uri);
 	cfg->uris = (char **)calloc(cfg->table_count, sizeof(char *));
 	if (cfg->uris == NULL) {
 		ret = ENOMEM;
@@ -1151,10 +1157,15 @@ create_uris(CONFIG *cfg)
 			ret = ENOMEM;
 			goto err;
 		}
-		memcpy(uri, cfg->uri, base_uri_len);
-		uri[base_uri_len] = uri[base_uri_len + 1] = '0';
-		uri[base_uri_len] = '0' + (i / 10);
-		uri[base_uri_len + 1] = '0' + (i % 10);
+		memcpy(uri, cfg->base_uri, base_uri_len);
+		/*
+		 * If there is only one table, just use base name.
+		 */
+		if (cfg->table_count > 1) {
+			uri[base_uri_len] = uri[base_uri_len + 1] = '0';
+			uri[base_uri_len] = '0' + (i / 10);
+			uri[base_uri_len + 1] = '0' + (i % 10);
+		}
 	}
 err:	if (ret != 0 && cfg->uris != NULL) {
 		for (i = 0; i < cfg->table_count; i++)
@@ -1165,7 +1176,7 @@ err:	if (ret != 0 && cfg->uris != NULL) {
 	return (ret);
 }
 
-int
+static int
 create_tables(CONFIG *cfg)
 {
 	WT_SESSION *session;
@@ -1177,7 +1188,7 @@ create_tables(CONFIG *cfg)
 	if (cfg->create == 0)
 		return (0);
 
-	uri = cfg->uri;
+	uri = cfg->base_uri;
 	if ((ret = cfg->conn->open_session(
 	    cfg->conn, NULL, cfg->sess_config, &session)) != 0) {
 		lprintf(cfg, ret, 0,
@@ -1185,12 +1196,11 @@ create_tables(CONFIG *cfg)
 		return (ret);
 	}
 	for (i = 0; i < cfg->table_count; i++) {
-		if (cfg->table_count > 1)
-			uri = cfg->uris[i];
+		uri = cfg->uris[i];
 		if ((ret = session->create(
 		    session, uri, cfg->table_config)) != 0) {
 			lprintf(cfg, ret, 0,
-			    "Error creating table %s", cfg->uri);
+			    "Error creating table %s", cfg->uris[i]);
 			return (ret);
 		}
 	}
@@ -1530,11 +1540,11 @@ main(int argc, char *argv[])
 	/* Build the URI from the table name. */
 	req_len = strlen("table:") +
 	    strlen(HELIUM_NAME) + strlen(cfg->table_name) + 2;
-	if ((cfg->uri = calloc(req_len, 1)) == NULL) {
+	if ((cfg->base_uri = calloc(req_len, 1)) == NULL) {
 		ret = enomem(cfg);
 		goto err;
 	}
-	snprintf(cfg->uri, req_len, "table:%s%s%s",
+	snprintf(cfg->base_uri, req_len, "table:%s%s%s",
 	    cfg->helium_mount == NULL ? "" : HELIUM_NAME,
 	    cfg->helium_mount == NULL ? "" : "/",
 	    cfg->table_name);
diff --git a/bench/wtperf/wtperf.h b/bench/wtperf/wtperf.h
index 15d296d00a0..c94ec10d8fd 100644
--- a/bench/wtperf/wtperf.h
+++ b/bench/wtperf/wtperf.h
@@ -83,7 +83,7 @@ typedef struct {
 struct __config {			/* Configuration struction */
 	const char *home;		/* WiredTiger home */
 	const char *monitor_dir;	/* Monitor output dir */
-	char *uri;			/* Object URI */
+	char *base_uri;			/* Object URI */
 	char **uris;			/* URIs if multiple tables */
 	const char *helium_mount;	/* Optional Helium mount point */
 
diff --git a/bench/wtperf/wtperf_opt.i b/bench/wtperf/wtperf_opt.i
index af50e7e9bf3..0fff7a14416 100644
--- a/bench/wtperf/wtperf_opt.i
+++ b/bench/wtperf/wtperf_opt.i
@@ -123,8 +123,8 @@ DEF_OPT_AS_CONFIG_STRING(table_config,
     "leaf_page_max=4kb,internal_page_max=64kb,allocation_size=4kb,",
     "table configuration string")
 DEF_OPT_AS_UINT32(table_count, 1,
-    "number of tables to run operations over. Operations are spread evenly "
-    "over the tables amongst all threads. Default 1, maximum 99.")
+    "number of tables to run operations over. Keys are divided evenly "
+    "over the tables. Default 1, maximum 99.")
 DEF_OPT_AS_STRING(threads, "", "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 "
diff --git a/dist/s_funcs.list b/dist/s_funcs.list
index b34564adda7..6ffb956f59e 100644
--- a/dist/s_funcs.list
+++ b/dist/s_funcs.list
@@ -22,6 +22,7 @@ __wt_log_scan
 __wt_nlpo2
 __wt_nlpo2_round
 __wt_print_huffman_code
+wiredtiger_config_parser_open
 wiredtiger_pack_int
 wiredtiger_pack_item
 wiredtiger_pack_str
diff --git a/dist/s_string.ok b/dist/s_string.ok
index a71cca62a8c..5f0d331e105 100644
--- a/dist/s_string.ok
+++ b/dist/s_string.ok
@@ -688,6 +688,7 @@ openfile
 os
 ovfl
 packv
+parserp
 patchp
 pathname
 pathnames
diff --git a/dist/s_symbols.list b/dist/s_symbols.list
index a66af1f8994..d3803bc3afa 100644
--- a/dist/s_symbols.list
+++ b/dist/s_symbols.list
@@ -1,4 +1,5 @@
 # List of OK external symbols.
+wiredtiger_config_parser_open
 wiredtiger_open
 wiredtiger_pack_close
 wiredtiger_pack_int
diff --git a/examples/c/Makefile.am b/examples/c/Makefile.am
index bd281df7130..5b43dcc2285 100644
--- a/examples/c/Makefile.am
+++ b/examples/c/Makefile.am
@@ -6,6 +6,7 @@ noinst_PROGRAMS = \
 	ex_all \
 	ex_call_center \
 	ex_config \
+	ex_config_parse \
 	ex_cursor \
 	ex_data_source \
 	ex_extending \
diff --git a/examples/c/ex_config_parse.c b/examples/c/ex_config_parse.c
new file mode 100644
index 00000000000..c6adc327c78
--- /dev/null
+++ b/examples/c/ex_config_parse.c
@@ -0,0 +1,166 @@
+/*-
+ * 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.
+ *
+ * ex_config_parse.c
+ *	This is an example demonstrating how to parse WiredTiger compatible
+ *	configuration strings.
+ */
+
+#include <stdio.h>
+#include <string.h>
+
+#include <wiredtiger.h>
+
+const char *home = NULL;
+
+int main(void)
+{
+	int ret;
+
+	/*! [Create a configuration parser] */
+	WT_CONFIG_ITEM k, v;
+	WT_CONFIG_PARSER *parser;
+	const char *config_string =
+	    "path=/dev/loop,page_size=1024,log=(archive=true,file_max=20MB)";
+
+	if ((ret = wiredtiger_config_parser_open(
+	    NULL, config_string, strlen(config_string), &parser)) != 0) {
+		fprintf(stderr, "Error creating configuration parser: %s\n",
+		    wiredtiger_strerror(ret));
+		return (ret);
+	}
+	if ((ret = parser->close(parser)) != 0) {
+		fprintf(stderr, "Error closing configuration parser: %s\n",
+		    wiredtiger_strerror(ret));
+		return (ret);
+	}
+	/*! [Create a configuration parser] */
+
+	if ((ret = wiredtiger_config_parser_open(
+	    NULL, config_string, strlen(config_string), &parser)) != 0) {
+		fprintf(stderr, "Error creating configuration parser: %s\n",
+		    wiredtiger_strerror(ret));
+		return (ret);
+	}
+
+	{
+	/*! [get] */
+	int64_t my_page_size;
+	/*
+	 * Retrieve the value of the integer configuration string "page_size".
+	 */
+	if ((ret = parser->get(parser, "page_size", &v)) != 0) {
+		fprintf(stderr,
+		    "page_size configuration: %s", wiredtiger_strerror(ret));
+		return (ret);
+	}
+	my_page_size = v.val;
+	/*! [get] */
+
+	ret = parser->close(parser);
+
+	(void)my_page_size;
+	}
+
+	{
+	if ((ret = wiredtiger_config_parser_open(
+	    NULL, config_string, strlen(config_string), &parser)) != 0) {
+		fprintf(stderr, "Error creating configuration parser: %s\n",
+		    wiredtiger_strerror(ret));
+		return (ret);
+	}
+	/*! [next] */
+	/*
+	 * Retrieve and print the values of the configuration strings.
+	 */
+	while ((ret = parser->next(parser, &k, &v)) == 0) {
+		printf("%.*s:", (int)k.len, k.str);
+		if (v.type == WT_CONFIG_ITEM_NUM)
+			printf("%d\n", (int)v.val);
+		else
+			printf("%.*s\n", (int)v.len, v.str);
+	}
+	/*! [next] */
+	ret = parser->close(parser);
+	}
+
+	if ((ret = wiredtiger_config_parser_open(
+	    NULL, config_string, strlen(config_string), &parser)) != 0) {
+		fprintf(stderr, "Error creating configuration parser: %s\n",
+		    wiredtiger_strerror(ret));
+		return (ret);
+	}
+
+	/*! [nested get] */
+	/*
+	 * Retrieve the value of the nested log file_max configuration string
+	 * using dot shorthand. Utilize the configuration parsing automatic
+	 * conversion of value strings into an integer.
+	 */
+	v.type = WT_CONFIG_ITEM_NUM;
+	if ((ret = parser->get(parser, "log.file_max", &v)) != 0) {
+		fprintf(stderr,
+		    "log.file_max configuration: %s", wiredtiger_strerror(ret));
+		return (ret);
+	}
+	printf("log file max: %d\n", (int)v.val);
+	/*! [nested get] */
+	ret = parser->close(parser);
+
+	if ((ret = wiredtiger_config_parser_open(
+	    NULL, config_string, strlen(config_string), &parser)) != 0) {
+		fprintf(stderr, "Error creating configuration parser: %s\n",
+		    wiredtiger_strerror(ret));
+		return (ret);
+	}
+	/*! [nested traverse] */
+	{
+	WT_CONFIG_PARSER *sub_parser;
+	while ((ret = parser->next(parser, &k, &v)) == 0) {
+		if (v.type == WT_CONFIG_ITEM_STRUCT) {
+			printf("Found nested configuration: %.*s\n",
+			    (int)k.len, k.str);
+			if ((ret = wiredtiger_config_parser_open(
+			    NULL, v.str, v.len, &sub_parser)) != 0) {
+				fprintf(stderr,
+				    "Error creating nested configuration "
+				    "parser: %s\n",
+				    wiredtiger_strerror(ret));
+				parser->close(parser);
+				return (ret);
+			}
+			while ((ret = sub_parser->next(
+			    sub_parser, &k, &v)) == 0)
+				printf("\t%.*s\n", (int)k.len, k.str);
+			sub_parser->close(sub_parser);
+		}
+	}
+	/*! [nested traverse] */
+	parser->close(parser);
+	}
+
+	return (0);
+}
diff --git a/examples/c/ex_data_source.c b/examples/c/ex_data_source.c
index daedce04075..953bb799340 100644
--- a/examples/c/ex_data_source.c
+++ b/examples/c/ex_data_source.c
@@ -339,30 +339,6 @@ my_open_cursor(WT_DATA_SOURCE *dsrc, WT_SESSION *session,
 	}
 
 	{
-	/*! [WT_EXTENSION config_strget] */
-	WT_CONFIG_ITEM v;
-	int64_t my_data_source_page_size;
-
-	/*
-	 * Retrieve the value of the integer type configuration string
-	 * "page_size" from a local string (as opposed to the provided
-	 * WT_CONFIG_ARG reference).
-	 */
-	const char *config_string = "path=/dev/loop,page_size=1024";
-
-	if ((ret = wt_api->config_strget(
-	    wt_api, session, config_string, "page_size", &v)) != 0) {
-		(void)wt_api->err_printf(wt_api, session,
-		    "page_size configuration: %s", wiredtiger_strerror(ret));
-		return (ret);
-	}
-	my_data_source_page_size = v.val;
-	/*! [WT_EXTENSION config_strget] */
-
-	(void)my_data_source_page_size;
-	}
-
-	{
 	/*! [WT_EXTENSION config_get] */
 	WT_CONFIG_ITEM v;
 	const char *my_data_source_key;
@@ -392,31 +368,6 @@ my_open_cursor(WT_DATA_SOURCE *dsrc, WT_SESSION *session,
 	}
 
 	{
-	/*! [WT_EXTENSION config scan] */
-	WT_CONFIG_ITEM k, v;
-	WT_CONFIG_SCAN *scan;
-
-	/*
-	 * Retrieve the value of the list type configuration string "paths".
-	 */
-	if ((ret = wt_api->config_get(
-	    wt_api, session, config, "paths", &v)) != 0) {
-		(void)wt_api->err_printf(wt_api, session,
-		    "paths configuration: %s", wiredtiger_strerror(ret));
-		return (ret);
-	}
-
-	/*
-	 * Step through the list of entries.
-	 */
-	ret = wt_api->config_scan_begin(wt_api, session, v.str, v.len, &scan);
-	while ((ret = wt_api->config_scan_next(wt_api, scan, &k, &v)) == 0)
-		printf("%.*s\n", (int)k.len, k.str);
-	ret = wt_api->config_scan_end(wt_api, scan);
-	/*! [WT_EXTENSION config scan] */
-	}
-
-	{
 	/*! [WT_EXTENSION collator config] */
 	/*
 	 * Configure the appropriate collator.
diff --git a/ext/datasources/helium/helium.c b/ext/datasources/helium/helium.c
index 1239c88befa..c8a6fe99bb0 100644
--- a/ext/datasources/helium/helium.c
+++ b/ext/datasources/helium/helium.c
@@ -2098,19 +2098,22 @@ helium_session_open_cursor(WT_DATA_SOURCE *wtds, WT_SESSION *session,
 	CURSOR *cursor;
 	DATA_SOURCE *ds;
 	WT_CONFIG_ITEM v;
+	WT_CONFIG_PARSER *config_parser;
 	WT_CURSOR *wtcursor;
 	WT_EXTENSION_API *wtext;
 	WT_SOURCE *ws;
-	int locked, ret = 0;
+	int locked, ret, t_ret;
 	const char *value;
 
 	*new_cursor = NULL;
 
+	config_parser = NULL;
 	cursor = NULL;
 	ds = (DATA_SOURCE *)wtds;
 	wtext = ds->wtext;
 	ws = NULL;
 	locked = 0;
+	ret = t_ret = 0;
 	value = NULL;
 
 	/* Allocate and initialize a cursor. */
@@ -2164,23 +2167,28 @@ helium_session_open_cursor(WT_DATA_SOURCE *wtds, WT_SESSION *session,
 		if ((ret = master_uri_get(wtds, session, uri, &value)) != 0)
 			goto err;
 
-		if ((ret = wtext->config_strget(
-		    wtext, session, value, "key_format", &v)) != 0)
+		if ((ret = wtext->config_parser_open(wtext,
+		    session, value, strlen(value), &config_parser)) != 0)
+			EMSG_ERR(wtext, session, ret,
+			    "Configuration string parser: %s",
+			    wtext->strerror(ret));
+		if ((ret = config_parser->get(
+		    config_parser, "key_format", &v)) != 0)
 			EMSG_ERR(wtext, session, ret,
 			    "key_format configuration: %s",
 			    wtext->strerror(ret));
 		ws->config_recno = v.len == 1 && v.str[0] == 'r';
 
-		if ((ret = wtext->config_strget(
-		    wtext, session, value, "value_format", &v)) != 0)
+		if ((ret = config_parser->get(
+		    config_parser, "value_format", &v)) != 0)
 			EMSG_ERR(wtext, session, ret,
 			    "value_format configuration: %s",
 			    wtext->strerror(ret));
 		ws->config_bitfield =
 		    v.len == 2 && isdigit(v.str[0]) && v.str[1] == 't';
 
-		if ((ret = wtext->config_strget(
-		    wtext, session, value, "helium_o_compress", &v)) != 0)
+		if ((ret = config_parser->get(
+		    config_parser, "helium_o_compress", &v)) != 0)
 			EMSG_ERR(wtext, session, ret,
 			    "helium_o_compress configuration: %s",
 			    wtext->strerror(ret));
@@ -2219,6 +2227,9 @@ err:		if (ws != NULL && locked)
 			ESET(unlock(wtext, session, &ws->lock));
 		cursor_destroy(cursor);
 	}
+	if (config_parser != NULL && (t_ret =
+	    (void)config_parser->close(config_parser)) != 0 && ret == 0)
+		ret = t_ret;
 	free((void *)value);
 	return (ret);
 }
@@ -2882,19 +2893,19 @@ helium_config_read(WT_EXTENSION_API *wtext, WT_CONFIG_ITEM *config,
     char **devicep, HE_ENV *envp, int *env_setp, int *flagsp)
 {
 	WT_CONFIG_ITEM k, v;
-	WT_CONFIG_SCAN *scan;
+	WT_CONFIG_PARSER *config_parser;
 	int ret = 0, tret;
 
 	*env_setp = 0;
 	*flagsp = 0;
 
-	/* Set up the scan of the configuration arguments list. */
-	if ((ret = wtext->config_scan_begin(
-	    wtext, NULL, config->str, config->len, &scan)) != 0)
+	/* Traverse the configuration arguments list. */
+	if ((ret = wtext->config_parser_open(
+	    wtext, NULL, config->str, config->len, &config_parser)) != 0)
 		ERET(wtext, NULL, ret,
-		    "WT_EXTENSION_API.config_scan_begin: %s",
+		    "WT_EXTENSION_API.config_parser_open: %s",
 		    wtext->strerror(ret));
-	while ((ret = wtext->config_scan_next(wtext, scan, &k, &v)) == 0) {
+	while ((ret = config_parser->next(config_parser, &k, &v)) == 0) {
 		if (string_match("helium_devices", k.str, k.len)) {
 			if ((*devicep = calloc(1, v.len + 1)) == NULL)
 				return (os_errno());
@@ -2924,13 +2935,11 @@ helium_config_read(WT_EXTENSION_API *wtext, WT_CONFIG_ITEM *config,
 		ret = 0;
 	if (ret != 0)
 		EMSG_ERR(wtext, NULL, ret,
-		    "WT_EXTENSION_API.config_scan_next: %s",
-		    wtext->strerror(ret));
+		    "WT_CONFIG_PARSER.next: %s", wtext->strerror(ret));
 
-err:	if ((tret = wtext->config_scan_end(wtext, scan)) != 0)
+err:	if ((tret = config_parser->close(config_parser)) != 0)
 		EMSG(wtext, NULL, tret,
-		    "WT_EXTENSION_API.config_scan_end: %s",
-		    wtext->strerror(tret));
+		    "WT_CONFIG_PARSER.close: %s", wtext->strerror(tret));
 
 	return (ret);
 }
@@ -3320,11 +3329,12 @@ wiredtiger_extension_init(WT_CONNECTION *connection, WT_CONFIG_ARG *config)
 	DATA_SOURCE *ds;
 	HELIUM_SOURCE *hs;
 	WT_CONFIG_ITEM k, v;
-	WT_CONFIG_SCAN *scan;
+	WT_CONFIG_PARSER *config_parser;
 	WT_EXTENSION_API *wtext;
 	int vmajor, vminor, ret = 0;
 	const char **p;
 
+	config_parser = NULL;
 	ds = NULL;
 
 	wtext = connection->get_extension_api(connection);
@@ -3357,12 +3367,12 @@ wiredtiger_extension_init(WT_CONNECTION *connection, WT_CONFIG_ARG *config)
 		    wtext->strerror(ret));
 
 	/* Step through the list of Helium sources, opening each one. */
-	if ((ret =
-	    wtext->config_scan_begin(wtext, NULL, v.str, v.len, &scan)) != 0)
+	if ((ret = wtext->config_parser_open(
+	    wtext, NULL, v.str, v.len, &config_parser)) != 0)
 		EMSG_ERR(wtext, NULL, ret,
-		    "WT_EXTENSION_API.config_scan_begin: config: %s",
+		    "WT_EXTENSION_API.config_parser_open: config: %s",
 		    wtext->strerror(ret));
-	while ((ret = wtext->config_scan_next(wtext, scan, &k, &v)) == 0) {
+	while ((ret = config_parser->next(config_parser, &k, &v)) == 0) {
 		if (string_match("helium_verbose", k.str, k.len)) {
 			verbose = v.val == 0 ? 0 : 1;
 			continue;
@@ -3372,12 +3382,13 @@ wiredtiger_extension_init(WT_CONNECTION *connection, WT_CONFIG_ARG *config)
 	}
 	if (ret != WT_NOTFOUND)
 		EMSG_ERR(wtext, NULL, ret,
-		    "WT_EXTENSION_API.config_scan_next: config: %s",
+		    "WT_CONFIG_PARSER.next: config: %s",
 		    wtext->strerror(ret));
-	if ((ret = wtext->config_scan_end(wtext, scan)) != 0)
+	if ((ret = config_parser->close(config_parser)) != 0)
 		EMSG_ERR(wtext, NULL, ret,
-		    "WT_EXTENSION_API.config_scan_end: config: %s",
+		    "WT_CONFIG_PARSER.close: config: %s",
 		    wtext->strerror(ret));
+	config_parser = NULL;
 
 	/* Find and open the database transaction store. */
 	if ((ret = helium_source_open_txn(ds)) != 0)
@@ -3414,6 +3425,8 @@ wiredtiger_extension_init(WT_CONNECTION *connection, WT_CONFIG_ARG *config)
 
 err:	if (ds != NULL)
 		ESET(helium_terminate((WT_DATA_SOURCE *)ds, NULL));
+	if (config_parser != NULL)
+		(void)config_parser->close(config_parser);
 	return (ret);
 }
 
diff --git a/lang/java/java_doc.i b/lang/java/java_doc.i
index fcb580ddbd4..83404b45508 100644
--- a/lang/java/java_doc.i
+++ b/lang/java/java_doc.i
@@ -40,3 +40,6 @@ COPYDOC(__wt_connection, WT_CONNECTION, add_data_source)
 COPYDOC(__wt_connection, WT_CONNECTION, add_collator)
 COPYDOC(__wt_connection, WT_CONNECTION, add_compressor)
 COPYDOC(__wt_connection, WT_CONNECTION, add_extractor)
+COPYDOC(__wt_config_parser, WT_CONFIG_PARSER, close)
+COPYDOC(__wt_config_parser, WT_CONFIG_PARSER, next)
+COPYDOC(__wt_config_parser, WT_CONFIG_PARSER, get)
diff --git a/src/btree/bt_discard.c b/src/btree/bt_discard.c
index 568e07f7fd1..c0c7a245a9f 100644
--- a/src/btree/bt_discard.c
+++ b/src/btree/bt_discard.c
@@ -317,6 +317,10 @@ __free_update_list(WT_SESSION_IMPL *session, WT_UPDATE *upd)
 
 	do {
 		next = upd->next;
+		/* Everything we free should be visible to everyone. */
+		WT_ASSERT(session,
+		    upd->txnid == WT_TXN_ABORTED ||
+		    __wt_txn_visible_all(session, upd->txnid));
 		__wt_free(session, upd);
 	} while ((upd = next) != NULL);
 }
diff --git a/src/btree/bt_evict.c b/src/btree/bt_evict.c
index d57162c06a9..fed52963de4 100644
--- a/src/btree/bt_evict.c
+++ b/src/btree/bt_evict.c
@@ -436,6 +436,9 @@ __wt_evict_file(WT_SESSION_IMPL *session, int syncop)
 	 */
 	__wt_evict_file_exclusive_on(session);
 
+	/* Make sure the oldest transaction ID is up-to-date. */
+	__wt_txn_update_oldest(session);
+
 	/*
 	 * We can't evict the page just returned to us, it marks our place in
 	 * the tree.  So, always walk one page ahead of the page being evicted.
diff --git a/src/config/config.c b/src/config/config.c
index c30c816de85..c0eb672015f 100644
--- a/src/config/config.c
+++ b/src/config/config.c
@@ -738,10 +738,8 @@ __wt_config_subgetraw(WT_SESSION_IMPL *session,
 __wt_config_subgets(WT_SESSION_IMPL *session,
     WT_CONFIG_ITEM *cfg, const char *key, WT_CONFIG_ITEM *value)
 {
-	WT_CONFIG_ITEM key_item;
-
-	key_item.str = key;
-	key_item.len = strlen(key);
+	WT_CONFIG_ITEM key_item =
+	    { key, strlen(key), 0, WT_CONFIG_ITEM_STRING };
 
 	return (__wt_config_subgetraw(session, cfg, &key_item, value));
 }
diff --git a/src/config/config_api.c b/src/config/config_api.c
index a5781a20c61..42f4c117b81 100644
--- a/src/config/config_api.c
+++ b/src/config/config_api.c
@@ -8,89 +8,98 @@
 #include "wt_internal.h"
 
 /*
- * wiredtiger_config_get --
- *	Given a NULL-terminated list of configuration strings, find the final
- * value for a given string key (external API version).
+ * __config_parser_close --
+ *      WT_CONFIG_PARSER->close method.
  */
-int
-wiredtiger_config_get(WT_SESSION *wt_session,
-     WT_CONFIG_ARG *cfg_arg, const char *key, WT_CONFIG_ITEM *cval)
+static int
+__config_parser_close(WT_CONFIG_PARSER *wt_config_parser)
 {
-	WT_SESSION_IMPL *session;
-	const char **cfg;
+	WT_CONFIG_PARSER_IMPL *config_parser;
 
-	session = (WT_SESSION_IMPL *)wt_session;
+	config_parser = (WT_CONFIG_PARSER_IMPL *)wt_config_parser;
 
-	if ((cfg = (const char **)cfg_arg) == NULL)
-		return (WT_NOTFOUND);
-	return (__wt_config_gets(session, cfg, key, cval));
+	if (config_parser == NULL)
+		return (EINVAL);
+
+	__wt_free(config_parser->session, config_parser);
+	return (0);
 }
 
 /*
- * wiredtiger_config_strget --
- *	Given a single configuration string, find the final value for a given
- * string key (external API version).
+ * __config_parser_get --
+ *      WT_CONFIG_PARSER->search method.
  */
-int
-wiredtiger_config_strget(WT_SESSION *wt_session,
-    const char *config, const char *key, WT_CONFIG_ITEM *cval)
+static int
+__config_parser_get(WT_CONFIG_PARSER *wt_config_parser,
+     const char *key, WT_CONFIG_ITEM *cval)
 {
-	const char *cfg_arg[] = { config, NULL };
+	WT_CONFIG_PARSER_IMPL *config_parser;
 
-	return (wiredtiger_config_get(
-	    wt_session, (WT_CONFIG_ARG *)cfg_arg, key, cval));
+	config_parser = (WT_CONFIG_PARSER_IMPL *)wt_config_parser;
+
+	if (config_parser == NULL)
+		return (EINVAL);
+
+	return (__wt_config_subgets(config_parser->session,
+	    &config_parser->config_item, key, cval));
 }
 
 /*
- * wiredtiger_config_scan_begin --
- *	Start a scan of a config string.
+ * __config_parser_next --
+ *	WT_CONFIG_PARSER->next method.
  */
-int
-wiredtiger_config_scan_begin(WT_SESSION *wt_session,
-    const char *str, size_t len, WT_CONFIG_SCAN **scanp)
+static int
+__config_parser_next(WT_CONFIG_PARSER *wt_config_parser,
+     WT_CONFIG_ITEM *key, WT_CONFIG_ITEM *cval)
 {
-	WT_CONFIG config, *scan;
-	WT_SESSION_IMPL *session;
+	WT_CONFIG_PARSER_IMPL *config_parser;
 
-	session = (WT_SESSION_IMPL *)wt_session;
+	config_parser = (WT_CONFIG_PARSER_IMPL *)wt_config_parser;
 
-	/* Note: allocate memory last to avoid cleanup. */
-	WT_CLEAR(config);
-	WT_RET(__wt_config_initn(session, &config, str, len));
-	WT_RET(__wt_calloc_def(session, 1, &scan));
-	*scan = config;
-	*scanp = (WT_CONFIG_SCAN *)scan;
-	return (0);
+	if (config_parser == NULL)
+		return (EINVAL);
+
+	return (__wt_config_next(&config_parser->config, key, cval));
 }
 
 /*
- * wiredtiger_config_scan_end --
- *	End a scan of a config string.
+ * wiredtiger_config_parser_open --
+ *	Create a configuration parser.
  */
 int
-wiredtiger_config_scan_end(WT_SESSION *wt_session, WT_CONFIG_SCAN *scan)
+wiredtiger_config_parser_open(WT_SESSION *wt_session,
+    const char *config, size_t len, WT_CONFIG_PARSER **config_parserp)
 {
-	WT_CONFIG *conf;
+	static const WT_CONFIG_PARSER stds = {
+		__config_parser_close,
+		__config_parser_next,
+		__config_parser_get
+	};
+	WT_CONFIG_ITEM config_item =
+	    { config, len, 0, WT_CONFIG_ITEM_STRING };
+	WT_CONFIG_PARSER_IMPL *config_parser;
+	WT_DECL_RET;
+	WT_SESSION_IMPL *session;
 
-	WT_UNUSED(wt_session);
+	*config_parserp = NULL;
+	session = (WT_SESSION_IMPL *)wt_session;
 
-	conf = (WT_CONFIG *)scan;
-	__wt_free(conf->session, scan);
-	return (0);
-}
+	WT_RET(__wt_calloc_def(session, 1, &config_parser));
+	config_parser->iface = stds;
+	config_parser->session = session;
 
-/*
- * wiredtiger_config_scan_next --
- *	Get the next key/value pair from a config scan.
- */
-int
-wiredtiger_config_scan_next(WT_SESSION *wt_session,
-    WT_CONFIG_SCAN *scan, WT_CONFIG_ITEM *key, WT_CONFIG_ITEM *value)
-{
-	WT_CONFIG *conf;
+	/*
+	 * Setup a WT_CONFIG_ITEM to be used for get calls and a WT_CONFIG
+	 * structure for iterations through the configuration string.
+	 */
+	memcpy(&config_parser->config_item, &config_item, sizeof(config_item));
+	WT_ERR(__wt_config_initn(
+	    session, &config_parser->config, config, len));
 
-	WT_UNUSED(wt_session);
+	if (ret == 0)
+		*config_parserp = (WT_CONFIG_PARSER *)config_parser;
+	else
+err:		__wt_free(session, config_parser);
 
-	conf = (WT_CONFIG *)scan;
-	return (__wt_config_next(conf, key, value));
+	return (ret);
 }
diff --git a/src/config/config_ext.c b/src/config/config_ext.c
index 7dd5445cc3c..26b3799d61c 100644
--- a/src/config/config_ext.c
+++ b/src/config/config_ext.c
@@ -8,6 +8,19 @@
 #include "wt_internal.h"
 
 /*
+ * __wt_ext_config_parser_open --
+ *	WT_EXTENSION_API->config_parser_open implementation
+ */
+int
+__wt_ext_config_parser_open(WT_EXTENSION_API *wt_ext, WT_SESSION *wt_session,
+    const char *config, size_t len, WT_CONFIG_PARSER **config_parserp)
+{
+	WT_UNUSED(wt_ext);
+	return (wiredtiger_config_parser_open(
+	    wt_session, config, len, config_parserp));
+}
+
+/*
  * __wt_ext_config_get --
  *	Given a NULL-terminated list of configuration strings, find the final
  * value for a given string key (external API version).
@@ -29,81 +42,3 @@ __wt_ext_config_get(WT_EXTENSION_API *wt_api,
 		return (WT_NOTFOUND);
 	return (__wt_config_gets(session, cfg, key, cval));
 }
-
-/*
- * __wt_ext_config_strget --
- *	Given a single configuration string, find the final value for a given
- * string key (external API version).
- */
-int
-__wt_ext_config_strget(WT_EXTENSION_API *wt_api,
-    WT_SESSION *wt_session, const char *config, const char *key,
-    WT_CONFIG_ITEM *cval)
-{
-	const char *cfg_arg[] = { config, NULL };
-
-	return (__wt_ext_config_get(
-	    wt_api, wt_session, (WT_CONFIG_ARG *)cfg_arg, key, cval));
-}
-
-/*
- * __wt_ext_config_scan_begin --
- *	Start a scan of a config string.
- * (external API only).
- */
-int
-__wt_ext_config_scan_begin(
-    WT_EXTENSION_API *wt_api, WT_SESSION *wt_session,
-    const char *str, size_t len, WT_CONFIG_SCAN **scanp)
-{
-	WT_CONFIG config, *scan;
-	WT_CONNECTION_IMPL *conn;
-	WT_SESSION_IMPL *session;
-
-	conn = (WT_CONNECTION_IMPL *)wt_api->conn;
-	if ((session = (WT_SESSION_IMPL *)wt_session) == NULL)
-		session = conn->default_session;
-
-	/* Note: allocate memory last to avoid cleanup. */
-	WT_CLEAR(config);
-	WT_RET(__wt_config_initn(session, &config, str, len));
-	WT_RET(__wt_calloc_def(session, 1, &scan));
-	*scan = config;
-	*scanp = (WT_CONFIG_SCAN *)scan;
-	return (0);
-}
-
-/*
- * __wt_ext_config_scan_end --
- *	End a scan of a config string.
- * (external API only).
- */
-int
-__wt_ext_config_scan_end(WT_EXTENSION_API *wt_api, WT_CONFIG_SCAN *scan)
-{
-	WT_CONFIG *conf;
-
-	WT_UNUSED(wt_api);
-
-	conf = (WT_CONFIG *)scan;
-	__wt_free(conf->session, scan);
-	return (0);
-}
-
-/*
- * __wt_ext_config_scan_next --
- *	Get the next key/value pair from a config scan.
- * (external API only).
- */
-int
-__wt_ext_config_scan_next(
-    WT_EXTENSION_API *wt_api, WT_CONFIG_SCAN *scan,
-    WT_CONFIG_ITEM *key, WT_CONFIG_ITEM *value)
-{
-	WT_CONFIG *conf;
-
-	WT_UNUSED(wt_api);
-
-	conf = (WT_CONFIG *)scan;
-	return (__wt_config_next(conf, key, value));
-}
diff --git a/src/conn/conn_api.c b/src/conn/conn_api.c
index 780ae6f6be5..bcbb8e3ceb8 100644
--- a/src/conn/conn_api.c
+++ b/src/conn/conn_api.c
@@ -105,11 +105,8 @@ __conn_get_extension_api(WT_CONNECTION *wt_conn)
 	conn->extension_api.scr_free = __wt_ext_scr_free;
 	conn->extension_api.collator_config = ext_collator_config;
 	conn->extension_api.collate = ext_collate;
+	conn->extension_api.config_parser_open = __wt_ext_config_parser_open;
 	conn->extension_api.config_get = __wt_ext_config_get;
-	conn->extension_api.config_strget = __wt_ext_config_strget;
-	conn->extension_api.config_scan_begin = __wt_ext_config_scan_begin;
-	conn->extension_api.config_scan_end = __wt_ext_config_scan_end;
-	conn->extension_api.config_scan_next = __wt_ext_config_scan_next;
 	conn->extension_api.metadata_insert = __wt_ext_metadata_insert;
 	conn->extension_api.metadata_remove = __wt_ext_metadata_remove;
 	conn->extension_api.metadata_search = __wt_ext_metadata_search;
@@ -123,6 +120,7 @@ __conn_get_extension_api(WT_CONNECTION *wt_conn)
 	conn->extension_api.transaction_notify = __wt_ext_transaction_notify;
 	conn->extension_api.transaction_oldest = __wt_ext_transaction_oldest;
 	conn->extension_api.transaction_visible = __wt_ext_transaction_visible;
+	conn->extension_api.version = wiredtiger_version;
 
 	return (&conn->extension_api);
 }
@@ -498,6 +496,20 @@ __conn_close(WT_CONNECTION *wt_conn, const char *config)
 	CONNECTION_API_CALL(conn, session, close, config, cfg);
 	WT_UNUSED(cfg);
 
+	/*
+	 * Rollback all running transactions.
+	 * We do this as a separate pass because an active transaction in one
+	 * session could cause trouble when closing a file, even if that
+	 * session never referenced that file.
+	 */
+	for (s = conn->sessions, i = 0; i < conn->session_cnt; ++s, ++i)
+		if (s->active && !F_ISSET(s, WT_SESSION_INTERNAL) &&
+		    F_ISSET(&s->txn, TXN_RUNNING)) {
+			wt_session = &s->iface;
+			WT_TRET(wt_session->rollback_transaction(
+			    wt_session, NULL));
+		}
+
 	/* Close open, external sessions. */
 	for (s = conn->sessions, i = 0; i < conn->session_cnt; ++s, ++i)
 		if (s->active && !F_ISSET(s, WT_SESSION_INTERNAL)) {
diff --git a/src/docs/Doxyfile b/src/docs/Doxyfile
index 5f7e5016892..d8f753b269b 100644
--- a/src/docs/Doxyfile
+++ b/src/docs/Doxyfile
@@ -1576,6 +1576,7 @@ PREDEFINED             = DOXYGEN \
                          __wt_compressor:=WT_COMPRESSOR \
                          __wt_config_arg:=WT_CONFIG_ARG \
                          __wt_config_item:=WT_CONFIG_ITEM \
+                         __wt_config_parser:=WT_CONFIG_PARSER \
                          __wt_config_scan:=WT_CONFIG_SCAN \
                          __wt_connection:=WT_CONNECTION \
                          __wt_cursor:=WT_CURSOR \
diff --git a/src/docs/command-line.dox b/src/docs/command-line.dox
index 52be68a1074..04daa4050cd 100644
--- a/src/docs/command-line.dox
+++ b/src/docs/command-line.dox
@@ -291,9 +291,6 @@ engine, or, if specified, for the URI on the command-line.
 <code>wt [-Vv] [-C config] [-h directory] stat [-a] [uri]</code>
 
 @subsection util_stat_options Options
-The \c stat command has no command-specific options.
-
-@subsection util_stat_options Options
 The following are command-specific options for the \c stat command:
 
 @par <code>-a</code>
diff --git a/src/docs/custom_data.dox b/src/docs/custom_data.dox
index b1ee8dfbd9e..22dd75dcc26 100644
--- a/src/docs/custom_data.dox
+++ b/src/docs/custom_data.dox
@@ -165,11 +165,6 @@ of a configuration string as follows:
 
 @snippet ex_data_source.c WT_EXTENSION config_get
 
-The WT_DATA_SOURCE::open_cursor method might retrieve the list value
-of a configuration string as follows:
-
-@snippet ex_data_source.c WT_EXTENSION config scan
-
 @subsection custom_ds_config_add Creating data-specific configuration strings
 
 Applications can add their own configuration strings to WiredTiger
diff --git a/src/docs/helium.dox b/src/docs/helium.dox
index cd6b47fb968..35e3886a8d6 100644
--- a/src/docs/helium.dox
+++ b/src/docs/helium.dox
@@ -103,7 +103,7 @@ WT_SESSION *session;
 
 /* Create and truncate the access table. */
 ret = session->create(session, "table:dev1/access",
-    "key_format=S,value_format=S,type=helium,helium_open_o_truncate=1");
+    "key_format=S,value_format=S,type=helium,helium_o_truncate=1");
 @endcode
 
 @section helium_notes Helium notes
diff --git a/src/include/cache.h b/src/include/cache.h
index 055041b7e6c..abbc2189f9d 100644
--- a/src/include/cache.h
+++ b/src/include/cache.h
@@ -9,7 +9,7 @@
  * Tuning constants: I hesitate to call this tuning, but we want to review some
  * number of pages from each file's in-memory tree for each page we evict.
  */
-#define	WT_EVICT_INT_SKEW  (1<<12)	/* Prefer leaf pages over internal
+#define	WT_EVICT_INT_SKEW  (1<<20)	/* Prefer leaf pages over internal
 					   pages by this many increments of the
 					   read generation. */
 #define	WT_EVICT_WALK_PER_FILE	10	/* Pages to visit per file */
diff --git a/src/include/config.h b/src/include/config.h
index d8837f0f368..c83d96c8a5e 100644
--- a/src/include/config.h
+++ b/src/include/config.h
@@ -33,6 +33,14 @@ struct __wt_config_entry {
 	const WT_CONFIG_CHECK *checks;		/* check array */
 };
 
+struct __wt_config_parser_impl {
+	WT_CONFIG_PARSER iface;
+
+	WT_SESSION_IMPL *session;
+	WT_CONFIG config;
+	WT_CONFIG_ITEM config_item;
+};
+
 /*
  * DO NOT EDIT: automatically built by dist/api_config.py.
  * configuration section: BEGIN
diff --git a/src/include/extern.h b/src/include/extern.h
index d1662717345..bd24cb02d61 100644
--- a/src/include/extern.h
+++ b/src/include/extern.h
@@ -529,27 +529,16 @@ extern int __wt_config_concat( WT_SESSION_IMPL *session,
     const char **config_ret);
 extern int __wt_conn_config_init(WT_SESSION_IMPL *session);
 extern void __wt_conn_config_discard(WT_SESSION_IMPL *session);
+extern int __wt_ext_config_parser_open(WT_EXTENSION_API *wt_ext,
+    WT_SESSION *wt_session,
+    const char *config,
+    size_t len,
+    WT_CONFIG_PARSER **config_parserp);
 extern int __wt_ext_config_get(WT_EXTENSION_API *wt_api,
     WT_SESSION *wt_session,
     WT_CONFIG_ARG *cfg_arg,
     const char *key,
     WT_CONFIG_ITEM *cval);
-extern int __wt_ext_config_strget(WT_EXTENSION_API *wt_api,
-    WT_SESSION *wt_session,
-    const char *config,
-    const char *key,
-    WT_CONFIG_ITEM *cval);
-extern int __wt_ext_config_scan_begin( WT_EXTENSION_API *wt_api,
-    WT_SESSION *wt_session,
-    const char *str,
-    size_t len,
-    WT_CONFIG_SCAN **scanp);
-extern int __wt_ext_config_scan_end(WT_EXTENSION_API *wt_api,
-    WT_CONFIG_SCAN *scan);
-extern int __wt_ext_config_scan_next( WT_EXTENSION_API *wt_api,
-    WT_CONFIG_SCAN *scan,
-    WT_CONFIG_ITEM *key,
-    WT_CONFIG_ITEM *value);
 extern int __wt_collator_config( WT_SESSION_IMPL *session,
     const char **cfg,
     WT_COLLATOR **collatorp);
diff --git a/src/include/txn.i b/src/include/txn.i
index cdfe697ee51..8ec1f52bff4 100644
--- a/src/include/txn.i
+++ b/src/include/txn.i
@@ -167,19 +167,23 @@ __wt_txn_visible(WT_SESSION_IMPL *session, uint64_t id)
 /*
  * __wt_txn_read_skip --
  *	Get the first visible update in a list (or NULL if none are visible),
- *	and report whether uncommitted changes were skipped.
+ *	and report whether there are an uncommitted changes in the list.
  */
 static inline WT_UPDATE *
 __wt_txn_read_skip(WT_SESSION_IMPL *session, WT_UPDATE *upd, int *skipp)
 {
+	WT_UPDATE *first_upd;
+
 	*skipp = 0;
-	while (upd != NULL && !__wt_txn_visible(session, upd->txnid)) {
-		if (upd->txnid != WT_TXN_ABORTED)
-			*skipp = 1;
-		upd = upd->next;
-	}
+	for (first_upd = NULL; upd != NULL; upd = upd->next)
+		if (upd->txnid != WT_TXN_ABORTED) {
+			if (!__wt_txn_visible(session, upd->txnid))
+				*skipp = 1;
+			else if (first_upd == NULL)
+				first_upd = upd;
+		}
 
-	return (upd);
+	return (first_upd);
 }
 
 /*
diff --git a/src/include/wiredtiger.in b/src/include/wiredtiger.in
index ac776e31ecd..c08b4d37206 100644
--- a/src/include/wiredtiger.in
+++ b/src/include/wiredtiger.in
@@ -71,9 +71,9 @@ extern "C" {
  *******************************************/
 struct __wt_collator;	    typedef struct __wt_collator WT_COLLATOR;
 struct __wt_compressor;	    typedef struct __wt_compressor WT_COMPRESSOR;
-struct __wt_config_arg;     typedef struct __wt_config_arg WT_CONFIG_ARG;
 struct __wt_config_item;    typedef struct __wt_config_item WT_CONFIG_ITEM;
-struct __wt_config_scan;    typedef struct __wt_config_scan WT_CONFIG_SCAN;
+struct __wt_config_parser;
+	typedef struct __wt_config_parser WT_CONFIG_PARSER;
 struct __wt_connection;	    typedef struct __wt_connection WT_CONNECTION;
 struct __wt_cursor;	    typedef struct __wt_cursor WT_CURSOR;
 struct __wt_data_source;    typedef struct __wt_data_source WT_DATA_SOURCE;
@@ -1910,7 +1910,7 @@ struct __wt_config_item {
 	 * list or string), the \c str field will reference the value of the
 	 * configuration string.
 	 *
-	 * The bytes referenced by \c str are <b>not</b> be nul-terminated,
+	 * The bytes referenced by \c str are <b>not</b> nul-terminated,
 	 * use the \c len field instead of a terminating nul byte.
 	 */
 	const char *str;
@@ -1951,93 +1951,94 @@ struct __wt_config_item {
 };
 
 /*!
- * @typedef WT_CONFIG_ARG
- *
- * A configuration object passed to some extension interfaces.  This is an
- * opaque type: configuration values can be queried using
- * WT_EXTENSION_API::config_get and wiredtiger_config_get.
- */
-
-/*!
- * @typedef WT_CONFIG_SCAN
- *
- * A handle for a scan through a configuration string.
- * This is an opaque type returned by WT_EXTENSION_API::config_scan_begin and
- * wiredtiger_config_scan_begin. Configuration values can be queried using
- * WT_EXTENSION_API::config_scan_next or wiredtiger_config_scan_next. Call
- * WT_EXTENSION_API::config_scan_end or wiredtiger_config_scan_end when
- * finished to release resources.
+ * Create a handle that can be used to parse or create configuration strings
+ * compatible with WiredTiger APIs.
+ * This API is outside the scope of a WiredTiger connection handle, since
+ * applications may need to generate configuration strings prior to calling
+ * ::wiredtiger_open.
+ * @param session the session handle (or NULL if none available), used for
+ *        error reporting if provided
+ * @param config the configuration string being parsed. The string must
+ *        remain valid for the lifetime of the parser handle.
+ * @param len the number of valid bytes in \c config
+ * @param[out] config_parserp A pointer to the newly opened handle
+ * @errors
  */
+int wiredtiger_config_parser_open(WT_SESSION *session,
+    const char *config, size_t len, WT_CONFIG_PARSER **config_parserp);
 
 /*!
- * Return the value of a configuration string.
+ * A handle that can be used to search and traverse configuration strings
+ * compatible with WiredTiger APIs.
+ * To parse the contents of a list or nested configuration string use a new
+ * configuration parser handle based on the content of the ::WT_CONFIG_ITEM
+ * retrieved from the parent configuration string.
  *
- * @param session the session handle (or NULL if none available)
- * @param key configuration key string
- * @param config the configuration information passed to an application
- * @param value the returned value
- * @errors
+ * @section config_parse_examples Configuration String Parsing examples
  *
- */
-int wiredtiger_config_get(WT_SESSION *session,
-    WT_CONFIG_ARG *config, const char *key, WT_CONFIG_ITEM *value);
-
-/*!
- * Return the value of a configuration string.
+ * This could be used in C to create a configuration parser as follows:
  *
- * @param session the session handle (or NULL if none available)
- * @param config a configuration string
- * @param key configuration key string
- * @param value the returned value
- * @errors
+ * @snippet ex_config_parse.c Create a configuration parser
  *
- */
-int wiredtiger_config_strget(WT_SESSION *session,
-    const char *config, const char *key, WT_CONFIG_ITEM *value);
-
-/*!
- * Return the list entries of a configuration string value.
- * This method steps through the entries found in the last returned
- * value from wiredtiger_config_get.  The last returned value
- * should be of type "list".
- *
- * @param session the session handle (or NULL if none available)
- * @param str the configuration string to scan
- * @param len the number of valid bytes in \c str
- * @param[out] scanp a handle used to scan the config string
- * @errors
+ * Once the parser has been created the content can be queried directly:
  *
- */
-int wiredtiger_config_scan_begin(WT_SESSION *session,
-    const char *str, size_t len, WT_CONFIG_SCAN **scanp);
-
-/*!
- * Release any resources allocated by
- * wiredtiger_config_scan_begin.
+ * @snippet ex_config_parse.c get
  *
- * @param session the session handle (or NULL if none available)
- * @param scan the configuration scanner, invalid after this call
- * @errors
+ * Or the content can be traversed linearly:
  *
- */
-int wiredtiger_config_scan_end(WT_SESSION *session, WT_CONFIG_SCAN *scan);
-
-/*!
- * Return the next key/value pair from a config string scan.
+ * @snippet ex_config_parse.c next
  *
- * If the string contains a list of items with no assigned value, the
- * items will be returned in \c key and the \c value will be set to the
- * boolean \c "true" value.
+ * Nested configuration values can be queried using a shorthand notation:
  *
- * @param session the session handle (or NULL if none available)
- * @param scan the configuration scanner
- * @param key the returned key
- * @param value the returned value
- * @errors
+ * @snippet ex_config_parse.c nested get
  *
+ * Nested configuration values can be traversed using multiple
+ * ::WT_CONFIG_PARSER handles:
+ *
+ * @snippet ex_config_parse.c nested traverse
  */
-int wiredtiger_config_scan_next(WT_SESSION *session,
-    WT_CONFIG_SCAN *scan, WT_CONFIG_ITEM *key, WT_CONFIG_ITEM *value);
+struct __wt_config_parser {
+
+	/*!
+	 * Close the configuration scanner releasing any resources.
+	 *
+	 * @param config_parser the configuration parser handle
+	 * @errors
+	 *
+	 */
+	int __F(close)(WT_CONFIG_PARSER *config_parser);
+
+	/*!
+	 * Return the next key/value pair.
+	 *
+	 * When iteration would pass the end of the configuration string
+	 * ::WT_NOTFOUND will be returned.
+	 *
+	 * If an item has no explicitly assigned value, the item will be
+	 * returned in \c key and the \c value will be set to the boolean
+	 * \c "true" value.
+	 *
+	 * @param config_parser the configuration parser handle
+	 * @param key the returned key
+	 * @param value the returned value
+	 * @errors
+	 *
+	 */
+	int __F(next)(WT_CONFIG_PARSER *config_parser,
+	    WT_CONFIG_ITEM *key, WT_CONFIG_ITEM *value);
+
+	/*!
+	 * Return the value of an item in the configuration string.
+	 *
+	 * @param config_parser the configuration parser handle
+	 * @param key configuration key string
+	 * @param value the returned value
+	 * @errors
+	 *
+	 */
+	int __F(get)(WT_CONFIG_PARSER *config_parser,
+	    const char *key, WT_CONFIG_ITEM *value);
+};
 
 #endif /* !defined(SWIG) */
 /*!
@@ -2134,6 +2135,7 @@ const char *wiredtiger_version(int *majorp, int *minorp, int *patchp);
 /*******************************************
  * Forward structure declarations for the extension API
  *******************************************/
+struct __wt_config_arg;     typedef struct __wt_config_arg WT_CONFIG_ARG;
 
 /*!
  * The interface implemented by applications to provide custom ordering of
diff --git a/src/include/wiredtiger_ext.h b/src/include/wiredtiger_ext.h
index 1f66c421027..acf7efad3d9 100644
--- a/src/include/wiredtiger_ext.h
+++ b/src/include/wiredtiger_ext.h
@@ -184,6 +184,12 @@ struct __wt_extension_api {
 	    WT_ITEM *first, WT_ITEM *second, int *cmp);
 
 	/*!
+	 * @copydoc wiredtiger_config_parser_open
+	 */
+	int (*config_parser_open)(WT_EXTENSION_API *wt_api, WT_SESSION *session,
+	    const char *config, size_t len, WT_CONFIG_PARSER **config_parserp);
+
+	/*!
 	 * Return the value of a configuration string.
 	 *
 	 * @param wt_api the extension handle
@@ -199,69 +205,6 @@ struct __wt_extension_api {
 	    WT_CONFIG_ARG *config, const char *key, WT_CONFIG_ITEM *value);
 
 	/*!
-	 * Return the value of a configuration string.
-	 *
-	 * @param wt_api the extension handle
-	 * @param session the session handle (or NULL if none available)
-	 * @param config a configuration string
-	 * @param key configuration key string
-	 * @param value the returned value
-	 * @errors
-	 *
-	 * @snippet ex_data_source.c WT_EXTENSION config_strget
-	 */
-	int (*config_strget)(WT_EXTENSION_API *wt_api, WT_SESSION *session,
-	    const char *config, const char *key, WT_CONFIG_ITEM *value);
-
-	/*!
-	 * Return the list entries of a configuration string value.
-	 * This method steps through the entries found in the last returned
-	 * value from WT_EXTENSION_API::config_get.  The last returned value
-	 * should be of type "list".
-	 *
-	 * @param wt_api the extension handle
-	 * @param session the session handle (or NULL if none available)
-	 * @param str the configuration string to scan
-	 * @param len the number of valid bytes in \c str
-	 * @param[out] scanp a handle used to scan the config string
-	 * @errors
-	 *
-	 * @snippet ex_data_source.c WT_EXTENSION config scan
-	 */
-	int (*config_scan_begin)(WT_EXTENSION_API *wt_api, WT_SESSION *session,
-	    const char *str, size_t len, WT_CONFIG_SCAN **scanp);
-
-	/*!
-	 * Release any resources allocated by
-	 * WT_EXTENSION_API::config_scan_begin.
-	 *
-	 * @param wt_api the extension handle
-	 * @param scan the configuration scanner, invalid after this call
-	 * @errors
-	 *
-	 * @snippet ex_data_source.c WT_EXTENSION config scan
-	 */
-	int (*config_scan_end)(WT_EXTENSION_API *wt_api, WT_CONFIG_SCAN *scan);
-
-	/*!
-	 * Return the next key/value pair from a config string scan.
-	 *
-	 * If the string contains a list of items with no assigned value, the
-	 * items will be returned in \c key and the \c value will be set to the
-	 * boolean \c "true" value.
-	 *
-	 * @param wt_api the extension handle
-	 * @param scan the configuration scanner
-	 * @param key the returned key
-	 * @param value the returned value
-	 * @errors
-	 *
-	 * @snippet ex_data_source.c WT_EXTENSION config scan
-	 */
-	int (*config_scan_next)(WT_EXTENSION_API *wt_api,
-	    WT_CONFIG_SCAN *scan, WT_CONFIG_ITEM *key, WT_CONFIG_ITEM *value);
-
-	/*!
 	 * Insert a row into the metadata if it does not already exist.
 	 *
 	 * @param wt_api the extension handle
@@ -428,8 +371,21 @@ struct __wt_extension_api {
 	 */
 	int (*transaction_visible)(WT_EXTENSION_API *wt_api,
 	    WT_SESSION *session, uint64_t transaction_id);
+
+	/*!
+	 * @copydoc wiredtiger_version
+	 */
+	const char *(*version)(int *majorp, int *minorp, int *patchp);
 };
 
+/*!
+ * @typedef WT_CONFIG_ARG
+ *
+ * A configuration object passed to some extension interfaces.  This is an
+ * opaque type: configuration values can be queried using
+ * WT_EXTENSION_API::config_get
+ */
+
 /*! @} */
 #endif /* SWIG */
 
diff --git a/src/include/wt_internal.h b/src/include/wt_internal.h
index 3ae89fc211e..19a805aa25f 100644
--- a/src/include/wt_internal.h
+++ b/src/include/wt_internal.h
@@ -93,6 +93,8 @@ struct __wt_config_check;
     typedef struct __wt_config_check WT_CONFIG_CHECK;
 struct __wt_config_entry;
     typedef struct __wt_config_entry WT_CONFIG_ENTRY;
+struct __wt_config_parser_impl;
+    typedef struct __wt_config_parser_impl WT_CONFIG_PARSER_IMPL;
 struct __wt_connection_impl;
     typedef struct __wt_connection_impl WT_CONNECTION_IMPL;
 struct __wt_connection_stats;
diff --git a/src/lsm/lsm_cursor.c b/src/lsm/lsm_cursor.c
index b51c9deeade..5076343bc4b 100644
--- a/src/lsm/lsm_cursor.c
+++ b/src/lsm/lsm_cursor.c
@@ -385,7 +385,7 @@ retry:	if (F_ISSET(clsm, WT_CLSM_MERGE)) {
 		 * generation number and retry if it has changed under us.
 		 */
 		if (clsm->cursors != NULL && (ngood < clsm->nchunks ||
-		    (F_ISSET(clsm, WT_CLSM_OPEN_READ) && nupdates > 0))) {
+		    (!F_ISSET(clsm, WT_CLSM_OPEN_READ) && nupdates > 0))) {
 			saved_gen = lsm_tree->dsk_gen;
 			locked = 0;
 			WT_ERR(__wt_lsm_tree_unlock(session, lsm_tree));
diff --git a/tools/wtperf_stats.py b/tools/wtperf_stats.py
index 388eb9fe24b..d9743055fff 100644
--- a/tools/wtperf_stats.py
+++ b/tools/wtperf_stats.py
@@ -76,6 +76,19 @@ def munge_dict(values_dict, abstime):
             next_val[title] = value
         ret.append(next_val)
 
+    # After building the series, eliminate constants
+    d0 = ret[0]
+    for t0, v0 in d0.items():
+        skip = True
+        for d in ret:
+            v = d[t0]
+            if v != v0:
+                skip = False
+                break
+        if skip:
+            for dicts in ret:
+                del dicts[t0]
+
     return ret
 
 def addPlotsToChart(chart, graph_data, wtstat_chart = False):