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commit    488f826c729bd570c36df369fa8ac90c9a5a1b46
Author:   Andres Freund <andres@anarazel.de>
Date:     Tue Oct 08 15:37:45 2024 +0000

    bufmgr: Return early in ScheduleBufferTagForWriteback() if fsync=off
    
    As pg_flush_data() doesn't do anything with fsync disabled, there's no point
    in tracking the buffer for writeback. Arguably the better fix would be to
    change pg_flush_data() to flush data even with fsync off, but that's a
    behavioral change, whereas this is just a small optimization.
    
    Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
    Reviewed-by: Noah Misch <noah@leadboat.com>
    Discussion: https://postgr.es/m/1f6b50a7-38ef-4d87-8246-786d39f46ab9@iki.fi


 src/backend/storage/buffer/bufmgr.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/backend/storage/buffer/bufmgr.c b/src/backend/storage/buffer/bufmgr.c
index 48520443001..b8680cc8fd4 100644
--- a/src/backend/storage/buffer/bufmgr.c
+++ b/src/backend/storage/buffer/bufmgr.c
@@ -5899,7 +5899,12 @@ ScheduleBufferTagForWriteback(WritebackContext *wb_context, IOContext io_context
 {
 	PendingWriteback *pending;
 
-	if (io_direct_flags & IO_DIRECT_DATA)
+	/*
+	 * As pg_flush_data() doesn't do anything with fsync disabled, there's no
+	 * point in tracking in that case.
+	 */
+	if (io_direct_flags & IO_DIRECT_DATA ||
+		!enableFsync)
 		return;
 
 	/*


[parent: c01fd93088da]