Add counts of the pages reviewed, skipped and written during a compaction

pass, report those statistics and the overall state of the file when the
compaction pass completes.

2 files changed, 55 insertions, 6 deletions

diff --git a/src/block/block_compact.c b/src/block/block_compact.c
index 3030a6bcfa9..cd304b848d4 100644
--- a/src/block/block_compact.c
+++ b/src/block/block_compact.c
@@ -8,7 +8,7 @@
 
 #include "wt_internal.h"
 
-static int __block_dump_avail(WT_SESSION_IMPL *, WT_BLOCK *);
+static int __block_dump_avail(WT_SESSION_IMPL *, WT_BLOCK *, bool);
 
 /*
  * __wt_block_compact_start --
@@ -32,12 +32,21 @@ __wt_block_compact_start(WT_SESSION_IMPL *session, WT_BLOCK *block)
 int
 __wt_block_compact_end(WT_SESSION_IMPL *session, WT_BLOCK *block)
 {
+	WT_DECL_RET;
+
 	WT_UNUSED(session);
 
 	/* Restore the original allocation plan. */
 	__wt_block_configure_first_fit(block, false);
 
-	return (0);
+	/* Dump the results of the compaction pass. */
+	if (WT_VERBOSE_ISSET(session, WT_VERB_COMPACT)) {
+		__wt_spin_lock(session, &block->live_lock);
+		ret = __block_dump_avail(session, block, false);
+		__wt_spin_unlock(session, &block->live_lock);
+	}
+
+	return (ret);
 }
 
 /*
@@ -66,12 +75,23 @@ __wt_block_compact_skip(WT_SESSION_IMPL *session, WT_BLOCK *block, bool *skipp)
 	if (fh->size <= WT_MEGABYTE)
 		return (0);
 
+	/*
+	 * Reset the compaction state information. This is done here, not in the
+	 * compaction "start" routine, because this function is called first to
+	 * determine if compaction is useful.
+	 */
+	block->compact_pct_tenths = 0;
+	block->compact_pages_reviewed = 0;
+	block->compact_pages_skipped = 0;
+	block->compact_pages_written = 0;
+
 	__wt_spin_lock(session, &block->live_lock);
 
+	/* Dump the current state of the file. */
 	if (WT_VERBOSE_ISSET(session, WT_VERB_COMPACT))
-		WT_ERR(__block_dump_avail(session, block));
+		WT_ERR(__block_dump_avail(session, block, true));
 
-	/* Sum the available bytes in the first 80% and 90% of the file. */
+	/* Sum the available bytes in the initial 80% and 90% of the file. */
 	avail_eighty = avail_ninety = 0;
 	ninety = fh->size - fh->size / 10;
 	eighty = fh->size - ((fh->size / 10) * 2);
@@ -173,6 +193,14 @@ __wt_block_compact_page_skip(WT_SESSION_IMPL *session,
 	}
 	__wt_spin_unlock(session, &block->live_lock);
 
+	if (WT_VERBOSE_ISSET(session, WT_VERB_COMPACT)) {
+		++block->compact_pages_reviewed;
+		if (*skipp)
+			++block->compact_pages_skipped;
+		else
+			++block->compact_pages_written;
+	}
+
 	return (ret);
 }
 
@@ -181,7 +209,7 @@ __wt_block_compact_page_skip(WT_SESSION_IMPL *session,
  *	Dump out the avail list so we can see what compaction will look like.
  */
 static int
-__block_dump_avail(WT_SESSION_IMPL *session, WT_BLOCK *block)
+__block_dump_avail(WT_SESSION_IMPL *session, WT_BLOCK *block, bool start)
 {
 	WT_EXTLIST *el;
 	WT_EXT *ext;
@@ -192,6 +220,20 @@ __block_dump_avail(WT_SESSION_IMPL *session, WT_BLOCK *block)
 	size = block->fh->size;
 
 	WT_RET(__wt_verbose(session, WT_VERB_COMPACT,
+	    "============ %s",
+	    start ? "testing for compaction" : "ending compaction pass"));
+
+	if (!start) {
+		WT_RET(__wt_verbose(session, WT_VERB_COMPACT,
+		    "pages reviewed: %" PRIuMAX,
+		    block->compact_pages_reviewed));
+		WT_RET(__wt_verbose(session, WT_VERB_COMPACT,
+		    "pages skipped: %" PRIuMAX, block->compact_pages_skipped));
+		WT_RET(__wt_verbose(session, WT_VERB_COMPACT,
+		    "pages written: %" PRIuMAX, block->compact_pages_written));
+	}
+
+	WT_RET(__wt_verbose(session, WT_VERB_COMPACT,
 	    "file size %" PRIuMAX "MB (%" PRIuMAX ") with %" PRIuMAX
 	    "%% space available %" PRIuMAX "MB (%" PRIuMAX ")",
 	    (uintmax_t)size / WT_MEGABYTE, (uintmax_t)size,
@@ -215,6 +257,10 @@ __block_dump_avail(WT_SESSION_IMPL *session, WT_BLOCK *block)
 		}
 
 #ifdef __VERBOSE_OUTPUT_PERCENTILE
+	/*
+	 * The verbose output always displays 10% buckets, running this code
+	 * as well also displays 1% buckets.
+	 */
 	for (i = 0; i < WT_ELEMENTS(percentile); ++i) {
 		v = percentile[i] * 512;
 		WT_RET(__wt_verbose(session, WT_VERB_COMPACT,
diff --git a/src/include/block.h b/src/include/block.h
index 4bff6c82783..f398ff494fd 100644
--- a/src/include/block.h
+++ b/src/include/block.h
@@ -244,7 +244,10 @@ struct __wt_block {
 	bool		ckpt_inprogress;/* Live checkpoint in progress */
 
 				/* Compaction support */
-	int	compact_pct_tenths;	/* Percent to compact */
+	int	 compact_pct_tenths;	/* Percent to compact */
+	uint64_t compact_pages_reviewed;/* Pages reviewed */
+	uint64_t compact_pages_skipped;	/* Pages skipped */
+	uint64_t compact_pages_written;	/* Pages rewritten */
 
 				/* Salvage support */
 	wt_off_t	slvg_off;	/* Salvage file offset */