database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-06-30 21:42:05 +03:00
Code Activity

Add new function WaitForParallelWorkersToAttach.

Browse Source 
Once this function has been called, we know that all workers have
started and attached to their error queues -- so if any of them
subsequently exit uncleanly, we'll be sure to throw an ERROR promptly.
Otherwise, users of the ParallelContext machinery must be careful not
to wait forever for a worker that has failed to start.  Parallel query
manages to work without needing this for reasons explained in new
comments added by this patch, but it's a useful primitive for other
parallel operations, such as the pending patch to make creating a
btree index run in parallel.

Amit Kapila, revised by me.  Additional review by Peter Geoghegan.

Discussion: http://postgr.es/m/CAA4eK1+e2MzyouF5bg=OtyhDSX+=Ao=3htN=T-r_6s3gCtKFiw@mail.gmail.com
This commit is contained in:
Robert Haas
2018-02-02 09:00:59 -05:00
parent a2a2205761
commit 9222c0d9ed
4 changed files with 163 additions and 11 deletions
Download Patch File Download Diff File Expand all files Collapse all files

4
src/include/access/parallel.h
View File

@ -43,7 +43,8 @@ typedef struct ParallelContext
void *private_memory;
shm_toc *toc;
ParallelWorkerInfo *worker;
bool *any_message_received;
int nknown_attached_workers;
bool *known_attached_workers;
} ParallelContext;
typedef struct ParallelWorkerContext
@ -62,6 +63,7 @@ extern ParallelContext *CreateParallelContext(const char *library_name, const ch
extern void InitializeParallelDSM(ParallelContext *pcxt);
extern void ReinitializeParallelDSM(ParallelContext *pcxt);
extern void LaunchParallelWorkers(ParallelContext *pcxt);
extern void WaitForParallelWorkersToAttach(ParallelContext *pcxt);
extern void WaitForParallelWorkersToFinish(ParallelContext *pcxt);
extern void DestroyParallelContext(ParallelContext *pcxt);
extern bool ParallelContextActive(void);