postgres.git / summary / log / commit / refs
commit 8fa4a1ac61189efffb8b851ee77e1bc87360c445
Author: Noah Misch <noah@leadboat.com>
Date: Thu Feb 01 21:44:19 2024 +0000
First released in: 17.0, 15.6, 16.2
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 9c08aea6a3090a396be334cc58c511edab05776a introduced
STRATEGY=WAL_LOG and made it the default.
Discussion: https://postgr.es/m/20240130195003.0a.nmisch@google.com
doc/src/sgml/monitoring.sgml | 5 +++++
src/backend/commands/dbcommands.c | 8 ++++++++
src/backend/utils/activity/wait_event.c | 3 +++
src/include/utils/wait_event.h | 3 ++-
4 files changed, 18 insertions(+), 1 deletion(-)
diff --git a/doc/src/sgml/monitoring.sgml b/doc/src/sgml/monitoring.sgml
index c72ad60fa0e..84e65002ff3 100644
--- a/doc/src/sgml/monitoring.sgml
+++ b/doc/src/sgml/monitoring.sgml
@@ -1519,6 +1519,11 @@ postgres 27093 0.0 0.0 30096 2752 ? Ss 11:34 0:00 postgres: ser
<entry><literal>TwophaseFileWrite</literal></entry>
<entry>Waiting for a write of a two phase state file.</entry>
</row>
+ <row>
+ <entry><literal>VersionFileSync</literal></entry>
+ <entry>Waiting for the version file to reach durable storage while
+ creating a database.</entry>
+ </row>
<row>
<entry><literal>VersionFileWrite</literal></entry>
<entry>Waiting for the version file to be written while creating a database.</entry>
diff --git a/src/backend/commands/dbcommands.c b/src/backend/commands/dbcommands.c
index 79c59889633..5ced6da20b6 100644
--- a/src/backend/commands/dbcommands.c
+++ b/src/backend/commands/dbcommands.c
@@ -507,6 +507,14 @@ 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);
diff --git a/src/backend/utils/activity/wait_event.c b/src/backend/utils/activity/wait_event.c
index 87c15b9c6f3..787525754a2 100644
--- a/src/backend/utils/activity/wait_event.c
+++ b/src/backend/utils/activity/wait_event.c
@@ -702,6 +702,9 @@ pgstat_get_wait_io(WaitEventIO w)
case WAIT_EVENT_TWOPHASE_FILE_WRITE:
event_name = "TwophaseFileWrite";
break;
+ case WAIT_EVENT_VERSION_FILE_SYNC:
+ event_name = "VersionFileSync";
+ break;
case WAIT_EVENT_VERSION_FILE_WRITE:
event_name = "VersionFileWrite";
break;
diff --git a/src/include/utils/wait_event.h b/src/include/utils/wait_event.h
index b578e2ec757..c814918d6ce 100644
--- a/src/include/utils/wait_event.h
+++ b/src/include/utils/wait_event.h
@@ -229,7 +229,8 @@ typedef enum
WAIT_EVENT_WAL_READ,
WAIT_EVENT_WAL_SYNC,
WAIT_EVENT_WAL_SYNC_METHOD_ASSIGN,
- WAIT_EVENT_WAL_WRITE
+ WAIT_EVENT_WAL_WRITE,
+ WAIT_EVENT_VERSION_FILE_SYNC
} WaitEventIO;
[parent: d493bed28f7f]