Sync PG_VERSION file in CREATE DATABASE.

An OS crash could leave PG_VERSION empty or missing.  The same symptom
appeared in a backup by block device snapshot, taken after the next
checkpoint and before the OS flushes the PG_VERSION blocks.  Device
snapshots are not a documented backup method, however.  Back-patch to
v15, where commit 9c08aea6a3 introduced
STRATEGY=WAL_LOG and made it the default.

Discussion: https://postgr.es/m/20240130195003.0a.nmisch@google.com
This commit is contained in:
Noah Misch 2024-02-01 13:44:19 -08:00
parent df220714e5
commit 0b6517a3b7
2 changed files with 9 additions and 0 deletions

View File

@ -508,6 +508,14 @@ CreateDirAndVersionFile(char *dbpath, Oid dbid, Oid tsid, bool isRedo)
}
pgstat_report_wait_end();
pgstat_report_wait_start(WAIT_EVENT_VERSION_FILE_SYNC);
if (pg_fsync(fd) != 0)
ereport(data_sync_elevel(ERROR),
(errcode_for_file_access(),
errmsg("could not fsync file \"%s\": %m", versionfile)));
fsync_fname(dbpath, true);
pgstat_report_wait_end();
/* Close the version file. */
CloseTransientFile(fd);

View File

@ -236,6 +236,7 @@ TIMELINE_HISTORY_WRITE "Waiting for a write of a newly created timeline history
TWOPHASE_FILE_READ "Waiting for a read of a two phase state file."
TWOPHASE_FILE_SYNC "Waiting for a two phase state file to reach durable storage."
TWOPHASE_FILE_WRITE "Waiting for a write of a two phase state file."
VERSION_FILE_SYNC "Waiting for the version file to reach durable storage while creating a database."
VERSION_FILE_WRITE "Waiting for the version file to be written while creating a database."
WALSENDER_TIMELINE_HISTORY_READ "Waiting for a read from a timeline history file during a walsender timeline command."
WAL_BOOTSTRAP_SYNC "Waiting for WAL to reach durable storage during bootstrapping."