On 12 November 2015 at 15:23, Amit Kapila <amit.kapil...@gmail.com> wrote: > On Wed, Nov 11, 2015 at 11:29 PM, Pavel Stehule <pavel.steh...@gmail.com> > wrote: >> >> Hi >> >> I have a first query >> >> I looked on EXPLAIN ANALYZE output and the numbers of filtered rows are >> differen >> > > Thanks for the report. The reason for this problem is that instrumentation > information from workers is getting aggregated multiple times. In > ExecShutdownGatherWorkers(), we call ExecParallelFinish where it > will wait for workers to finish and then accumulate stats from workers. > Now ExecShutdownGatherWorkers() could be called multiple times > (once we read all tuples from workers, at end of node) and it should be > ensured that repeated calls should not try to redo the work done by first > call. > The same is ensured for tuplequeues, but not for parallel executor info. > I think we can safely assume that we need to call ExecParallelFinish() only > when there are workers started by the Gathers node, so on those lines > attached patch should fix the problem.
That fixes the count issue for me, although not the number of buffers hit, or the actual time taken. Thom -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
