database/postgres
database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-06-01 14:21:49 +03:00
Code

Prevent parallel index build in a standalone backend.

Browse Source 
This can't work if there's no postmaster, and indeed the code got an
assertion failure trying.  There should be a check on IsUnderPostmaster
gating the use of parallelism, as the planner has for ordinary
parallel queries.

Commit 40d964ec9 got this right, so follow its model of checking
IsUnderPostmaster at the same place where we check for
max_parallel_maintenance_workers == 0.  In general, new code
implementing parallel utility operations should do the same.

Report and patch by Yulin Pei, cosmetically adjusted by me.
Back-patch to v11 where this code came in.

Discussion: https://postgr.es/m/HK0PR01MB22747D839F77142D7E76A45DF4F50@HK0PR01MB2274.apcprd01.prod.exchangelabs.com
This commit is contained in:
Tom Lane 2020-11-30 14:38:00 -05:00
parent caecab229a
commit 942e441ee8
1 changed files with 6 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
src/backend/optimizer/plan/planner.c
View File

@ -6090,8 +6090,12 @@ plan_create_index_workers(Oid tableOid, Oid indexOid)
double reltuples;
double allvisfrac;
/* Return immediately when parallelism disabled */
if (dynamic_shared_memory_type == DSM_IMPL_NONE ||
/*
* We don't allow performing parallel operation in standalone backend or
* when parallelism is disabled.
*/
if (!IsUnderPostmaster ||
dynamic_shared_memory_type == DSM_IMPL_NONE ||
max_parallel_maintenance_workers == 0)
return 0;