postgres.git / summary / log / commit / refs

commit    c52e0e2afc0c8ca2de4e03fc8478d89b4d5e7fce
Author:   Simon Riggs <simon@2ndQuadrant.com>
Date:     Mon Dec 03 18:56:41 2012 +0000

    Avoid holding vmbuffer pin after VACUUM.
    During VACUUM if we pause to perform a cycle
    of index cleanup we drop the vmbuffer pin,
    so we should do the same thing when heap
    scan completes. This avoids holding vmbuffer
    pin across the main index cleanup in VACUUM,
    which could be minutes or hours longer than
    necessary for correctness.
    
    Bug report and suggested fix from Pavan Deolasee


 src/backend/commands/vacuumlazy.c | 16 +++++++++-------
 1 file changed, 9 insertions(+), 7 deletions(-)

diff --git a/src/backend/commands/vacuumlazy.c b/src/backend/commands/vacuumlazy.c
index 89de6693ae2..2d18c54a5e7 100644
--- a/src/backend/commands/vacuumlazy.c
+++ b/src/backend/commands/vacuumlazy.c
@@ -831,6 +831,15 @@ lazy_scan_heap(Relation onerel, LVRelStats *vacrelstats,
 														 vacrelstats->scanned_pages,
 														 num_tuples);
 
+	/*
+	 * Release any remaining pin on visibility map page.
+	 */
+	if (BufferIsValid(vmbuffer))
+	{
+		ReleaseBuffer(vmbuffer);
+		vmbuffer = InvalidBuffer;
+	}
+
 	/* If any tuples need to be deleted, perform final vacuum cycle */
 	/* XXX put a threshold on min number of tuples here? */
 	if (vacrelstats->num_dead_tuples > 0)
@@ -848,13 +857,6 @@ lazy_scan_heap(Relation onerel, LVRelStats *vacrelstats,
 		vacrelstats->num_index_scans++;
 	}
 
-	/* Release the pin on the visibility map page */
-	if (BufferIsValid(vmbuffer))
-	{
-		ReleaseBuffer(vmbuffer);
-		vmbuffer = InvalidBuffer;
-	}
-
 	/* Do post-vacuum cleanup and statistics update for each index */
 	for (i = 0; i < nindexes; i++)
 		lazy_cleanup_index(Irel[i], indstats[i], vacrelstats);


[parent: 17164ccdf870]