Amit, Rafia, nodeIndexscan.c, unlike nodeSeqscan.c, thinks that a parallel-aware scan will always be executed in parallel mode. But that's not true: an Execute message with a non-zero row count could cause us to abandon planned parallelism and execute the plan serially. I believe this would cause a core dump. We definitely core dump with the following small patch, which causes parallelism to always be abandoned:
diff --git a/src/backend/executor/execMain.c b/src/backend/executor/execMain.c index f5cd65d..fc4de48 100644 --- a/src/backend/executor/execMain.c +++ b/src/backend/executor/execMain.c @@ -1596,8 +1596,7 @@ ExecutePlan(EState *estate, * when writing into a relation, because no database changes are allowed * in parallel mode. */ - if (numberTuples || dest->mydest == DestIntoRel) - use_parallel_mode = false; + use_parallel_mode = false; if (use_parallel_mode) EnterParallelMode(); I believe this defect was introduced by 5262f7a4fc44f651241d2ff1fa688dd664a34874 and that nodeIndexonlyscan.c has the same defect as of 0414b26bac09379a4cbf1fbd847d1cee2293c5e4. Please fix. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers