Add new function WaitForParallelWorkersToAttach. 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_6s3gctk...@mail.gmail.com Branch ------ master Details ------- https://git.postgresql.org/pg/commitdiff/9222c0d9ed9794d54fc3f5101498829eaec9e799 Modified Files -------------- src/backend/access/transam/parallel.c | 152 +++++++++++++++++++++++++++++++-- src/backend/executor/nodeGather.c | 9 +- src/backend/executor/nodeGatherMerge.c | 9 +- src/include/access/parallel.h | 4 +- 4 files changed, 163 insertions(+), 11 deletions(-)