postgres.git / summary / log / commit / refs

commit    d431644b43fcce9b7c2f677db18452b0ee216b42
Author:   Heikki Linnakangas <heikki.linnakangas@iki.fi>
Date:     Tue Jul 04 14:57:03 2023 +0000
First released in: 17.0, 11.21, 12.16, 13.12, 14.9, 15.4, 16.0

    Ensure that creation of an empty relfile is fsync'd at checkpoint.
    
    If you create a table and don't insert any data into it, the relation file
    is never fsync'd. You don't lose data, because an empty table doesn't have
    any data to begin with, but if you crash and lose the file, subsequent
    operations on the table will fail with "could not open file" error.
    
    To fix, register an fsync request in mdcreate(), like we do for mdwrite().
    
    Per discussion, we probably should also fsync the containing directory
    after creating a new file. But that's a separate and much wider issue.
    
    Backpatch to all supported versions.
    
    Reviewed-by: Andres Freund, Thomas Munro
    Discussion: https://www.postgresql.org/message-id/d47d8122-415e-425c-d0a2-e0160829702d%40iki.fi


 src/backend/storage/smgr/md.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/backend/storage/smgr/md.c b/src/backend/storage/smgr/md.c
index 30dbc02f823..fdecbad1709 100644
--- a/src/backend/storage/smgr/md.c
+++ b/src/backend/storage/smgr/md.c
@@ -239,6 +239,9 @@ mdcreate(SMgrRelation reln, ForkNumber forknum, bool isRedo)
 	mdfd = &reln->md_seg_fds[forknum][0];
 	mdfd->mdfd_vfd = fd;
 	mdfd->mdfd_segno = 0;
+
+	if (!SmgrIsTemp(reln))
+		register_dirty_segment(reln, forknum, mdfd);
 }
 
 /*


[parent: af8f9ec66bd1]