0003-Remove-unnecessary-smgrimmedsync-when-creating-unlog.patch

From 409c47797b3beba03f88e9386b0f0967ba28bf41 Mon Sep 17 00:00:00 2001
From: Heikki Linnakangas <heikki.linnakangas@iki.fi>
Date: Thu, 27 Jan 2022 21:24:04 +0200
Subject: [PATCH 3/3] Remove unnecessary smgrimmedsync() when creating unlogged
 table.

In the passing, fix a comment in smgrDoPendingSyncs().

TODO: only push this after we have fixed smgrcreate() to register the new
relation for fsyncing at next checkpoint.
---
 src/backend/access/heap/heapam_handler.c | 8 +-------
 src/backend/catalog/storage.c            | 2 +-
 2 files changed, 2 insertions(+), 8 deletions(-)

diff --git a/src/backend/access/heap/heapam_handler.c b/src/backend/access/heap/heapam_handler.c
index 39ef8a0b77d..a7259936fec 100644
--- a/src/backend/access/heap/heapam_handler.c
+++ b/src/backend/access/heap/heapam_handler.c
@@ -597,12 +597,7 @@ heapam_relation_set_new_filenode(Relation rel,
 
 	/*
 	 * If required, set up an init fork for an unlogged table so that it can
-	 * be correctly reinitialized on restart.  An immediate sync is required
-	 * even if the page has been logged, because the write did not go through
-	 * shared_buffers and therefore a concurrent checkpoint may have moved the
-	 * redo pointer past our xlog record.  Recovery may as well remove it
-	 * while replaying, for example, XLOG_DBASE_CREATE or XLOG_TBLSPC_CREATE
-	 * record. Therefore, logging is necessary even if wal_level=minimal.
+	 * be correctly reinitialized on restart.
 	 */
 	if (persistence == RELPERSISTENCE_UNLOGGED)
 	{
@@ -611,7 +606,6 @@ heapam_relation_set_new_filenode(Relation rel,
 			   rel->rd_rel->relkind == RELKIND_TOASTVALUE);
 		smgrcreate(srel, INIT_FORKNUM, false);
 		log_smgrcreate(newrnode, INIT_FORKNUM);
-		smgrimmedsync(srel, INIT_FORKNUM);
 	}
 
 	smgrclose(srel);
diff --git a/src/backend/catalog/storage.c b/src/backend/catalog/storage.c
index 9b8075536a7..468b6dafcb6 100644
--- a/src/backend/catalog/storage.c
+++ b/src/backend/catalog/storage.c
@@ -726,7 +726,7 @@ smgrDoPendingSyncs(bool isCommit, bool isParallelWorker)
 		/*
 		 * We emit newpage WAL records for smaller relations.
 		 *
-		 * Small WAL records have a chance to be emitted along with other
+		 * Small WAL records have a chance to be flushed along with other
 		 * backends' WAL records.  We emit WAL records instead of syncing for
 		 * files that are smaller than a certain threshold, expecting faster
 		 * commit.  The threshold is defined by the GUC wal_skip_threshold.
-- 
2.30.2