0001-Reset-LH_PAGE_HAS_DEAD_TUPLES-flag-on-standby-when.patch

From aa9e0c0fbb3d15b440b53d8e038e381f673f7fda Mon Sep 17 00:00:00 2001
From: ashu <ashu@localhost.localdomain>
Date: Thu, 16 Mar 2017 12:05:59 +0530
Subject: [PATCH] Reset LH_PAGE_HAS_DEAD_TUPLES flag on standby when replaying
 XLOG_HASH_VACUUM_ONE_PAGE record.

---
 src/backend/access/hash/hash_xlog.c  | 8 ++++++++
 src/backend/access/hash/hashinsert.c | 8 ++++++++
 2 files changed, 16 insertions(+)

diff --git a/src/backend/access/hash/hash_xlog.c b/src/backend/access/hash/hash_xlog.c
index cabf0fd..53f2dbc 100644
--- a/src/backend/access/hash/hash_xlog.c
+++ b/src/backend/access/hash/hash_xlog.c
@@ -1078,6 +1078,7 @@ hash_xlog_vacuum_one_page(XLogReaderState *record)
 	Buffer metabuf;
 	Page page;
 	XLogRedoAction action;
+	HashPageOpaque pageopaque;
 
 	xldata = (xl_hash_vacuum_one_page *) XLogRecGetData(record);
 
@@ -1126,6 +1127,13 @@ hash_xlog_vacuum_one_page(XLogReaderState *record)
 				PageIndexMultiDelete(page, unused, unend - unused);
 		}
 
+		/*
+		 * Mark the page as not containing any LP_DEAD items. See comments
+		 * in _hash_vacuum_one_page().
+		 */
+		pageopaque = (HashPageOpaque) PageGetSpecialPointer(page);
+		pageopaque->hasho_flag &= ~LH_PAGE_HAS_DEAD_TUPLES;
+
 		PageSetLSN(page, lsn);
 		MarkBufferDirty(buffer);
 	}
diff --git a/src/backend/access/hash/hashinsert.c b/src/backend/access/hash/hashinsert.c
index 8b6d0a0..8640e85 100644
--- a/src/backend/access/hash/hashinsert.c
+++ b/src/backend/access/hash/hashinsert.c
@@ -374,6 +374,14 @@ _hash_vacuum_one_page(Relation rel, Buffer metabuf, Buffer buf,
 
 		PageIndexMultiDelete(page, deletable, ndeletable);
 
+		/*
+		 * Mark the page as not containing any LP_DEAD items. This is not
+		 * certainly true (there might be some that have recently been marked,
+		 * but weren't included in our target-item list), but it will almost
+		 * always be true and it doesn't seem worth an additional page scan
+		 * to check it. Remember that LH_PAGE_HAS_DEAD_TUPLES is only a hint
+		 * anyway.
+		 */
 		pageopaque = (HashPageOpaque) PageGetSpecialPointer(page);
 		pageopaque->hasho_flag &= ~LH_PAGE_HAS_DEAD_TUPLES;
 
-- 
1.8.3.1