mirror/postgresql
2
0
Fork 0
mirror of https://git.postgresql.org/git/postgresql.git synced 2025-01-06 15:24:56 +08:00
Code Issues Packages Projects Releases Wiki Activity

Add a bit more locking to vac_update_relstats and vac_update_dbstats

Browse Source 
to make them comparable to what UpdateStats does in the same situation.
I'm not certain two instances of vac_update_relstats could run in
parallel for the same relation, but parallel invocations of vac_update_dbstats
do seem possible.
This commit is contained in:
Tom Lane 2003-10-02 23:19:44 +00:00
parent bea8af9152
commit 19c90bcc25
1 changed files with 11 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
src/backend/commands/vacuum.c
View File

@ -13,7 +13,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/commands/vacuum.c,v 1.262 2003/09/29 00:05:25 petere Exp $
* $Header: /cvsroot/pgsql/src/backend/commands/vacuum.c,v 1.263 2003/10/02 23:19:44 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -520,6 +520,9 @@ vac_update_relstats(Oid relid, BlockNumber num_pages, double num_tuples,
elog(ERROR, "pg_class entry for relid %u vanished during vacuuming",
relid);
/* ensure no one else does this at the same time */
LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
/* overwrite the existing statistics in the tuple */
pgcform = (Form_pg_class) GETSTRUCT(&rtup);
pgcform->relpages = (int32) num_pages;
@ -533,6 +536,8 @@ vac_update_relstats(Oid relid, BlockNumber num_pages, double num_tuples,
if (!hasindex)
pgcform->relhaspkey = false;
LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
/*
* Invalidate the tuple in the catcaches; this also arranges to flush
* the relation's relcache entry. (If we fail to commit for some
@ -588,12 +593,17 @@ vac_update_dbstats(Oid dbid,
if (!HeapTupleIsValid(tuple))
elog(ERROR, "could not find tuple for database %u", dbid);
/* ensure no one else does this at the same time */
LockBuffer(scan->rs_cbuf, BUFFER_LOCK_EXCLUSIVE);
dbform = (Form_pg_database) GETSTRUCT(tuple);
/* overwrite the existing statistics in the tuple */
dbform->datvacuumxid = vacuumXID;
dbform->datfrozenxid = frozenXID;
LockBuffer(scan->rs_cbuf, BUFFER_LOCK_UNLOCK);
/* invalidate the tuple in the cache and write the buffer */
CacheInvalidateHeapTuple(relation, tuple);
WriteNoReleaseBuffer(scan->rs_cbuf);