database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-06-29 10:41:53 +03:00
Code Activity

Update parallel executor support to reuse the same DSM.

Browse Source 
Commit b0b0d84b3d purported to make it
possible to relaunch workers using the same parallel context, but it had
an unpleasant race condition: we might reinitialize after the workers
have sent their last control message but before they have dettached the
DSM, leaving to crashes.  Repair by introducing a new ParallelContext
operation, ReinitializeParallelDSM.

Adjust execParallel.c to use this new support, so that we can rescan a
Gather node by relaunching workers but without needing to recreate the
DSM.

Amit Kapila, with some adjustments by me.  Extracted from latest parallel
sequential scan patch.
This commit is contained in:
Robert Haas
2015-10-30 10:43:00 +01:00
parent c6baec92fc
commit 3a1f8611f2
6 changed files with 166 additions and 108 deletions
Download Patch File Download Diff File Expand all files Collapse all files

1
src/include/access/parallel.h
View File

@ -56,6 +56,7 @@ extern bool InitializingParallelWorker;
extern ParallelContext *CreateParallelContext(parallel_worker_main_type entrypoint, int nworkers);
extern ParallelContext *CreateParallelContextForExternalFunction(char *library_name, char *function_name, int nworkers);
extern void InitializeParallelDSM(ParallelContext *);
extern void ReinitializeParallelDSM(ParallelContext *pcxt);
extern void LaunchParallelWorkers(ParallelContext *);
extern void WaitForParallelWorkersToFinish(ParallelContext *);
extern void DestroyParallelContext(ParallelContext *);