pgsql: fsync pg_logical/mappings in CheckPointLogicalRewriteHeap().

fsync pg_logical/mappings in CheckPointLogicalRewriteHeap().

While individual logical rewrite files were synced to disk, the directory was
not. On some filesystems that could lead to loosing directory entries after a
crash.

Reported-By: Tom Lane <tgl@sss.pgh.pa.us>
Author: Nathan Bossart <bossartn@amazon.com>
Discussion: https://postgr.es/m/867F2E29-2782-4869-970E-B984C6D35A8F@amazon.com
Backpatch: 10-

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/1fabec7d7c389181424fa7881632a415584ca7b7

Modified Files
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src/backend/access/heap/rewriteheap.c | 3 +++
1 file changed, 3 insertions(+)