From: Heikki Linnakangas <heikki.linnakangas@iki.fi>
Date: Mon, 18 Nov 2013 07:51:09 +0000 (+0200)
Subject: Count locked pages that don't need vacuuming as scanned.
X-Git-Tag: REL9_2_6~26
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=3379263b6ded774acb96288d1e67caa37dcba0de;p=postgresql

Count locked pages that don't need vacuuming as scanned.

Previously, if VACUUM skipped vacuuming a page because it's pinned, it
didn't count that page as scanned. However, that meant that relfrozenxid
was not bumped up either, which prevented anti-wraparound vacuum from
doing its job.

Report by Миша Тюрин, analysis and patch by Sergey Burladyn and Jeff Janes.
Backpatch to 9.2, where the skip-locked-pages behavior was introduced.
---

diff --git a/src/backend/commands/vacuumlazy.c b/src/backend/commands/vacuumlazy.c
index 28f169e59c..782f59e64d 100644
--- a/src/backend/commands/vacuumlazy.c
+++ b/src/backend/commands/vacuumlazy.c
@@ -589,6 +589,7 @@ lazy_scan_heap(Relation onerel, LVRelStats *vacrelstats,
 			if (!lazy_check_needs_freeze(buf))
 			{
 				UnlockReleaseBuffer(buf);
+				vacrelstats->scanned_pages++;
 				continue;
 			}
 			LockBuffer(buf, BUFFER_LOCK_UNLOCK);