On Fri, Oct 16, 2015 at 2:10 PM, Haribabu Kommi <kommi.harib...@gmail.com> wrote: > On Thu, Oct 15, 2015 at 11:45 PM, Amit Kapila <amit.kapil...@gmail.com> wrote: >> On Thu, Oct 15, 2015 at 5:39 PM, Haribabu Kommi <kommi.harib...@gmail.com> >> wrote: >>> >>> >>> >>> On Thu, Oct 15, 2015 at 6:32 PM, Amit Kapila <amit.kapil...@gmail.com> >>> wrote: >>> > On Wed, Oct 14, 2015 at 3:29 AM, Robert Haas <robertmh...@gmail.com> >>> > wrote: >>> > I think this got messed up while rebasing on top of Gather node >>> > changes, but nonetheless, I have changed it such that PartialSeqScan >>> > node handling is after SeqScan. >>> >>> Currently, the explain analyze of parallel seq scan plan is not showing >>> the allocated number of workers >>> including the planned workers.I feel this information is good for users in >>> understanding the performance >>> difference that is coming with parallel seq scan. It may be missed in >>> recent patch series. It was discussed >>> in[1]. >>> >> >> I am aware of that and purposefully kept it for a consecutive patch. >> There are other things as well which I have left out from this patch >> and those are: >> a. Early stop of executor for Rescan purpose >> b. Support of pushdown for plans containing InitPlan and SubPlans >> >> Then there is more related work like >> a. Support for prepared statements >> > > OK. > > During the test with latest patch, I found a dead lock between worker > and backend > on relation lock. To minimize the test scenario, I changed the number > of pages required > to start one worker to 1 and all parallel cost parameters as zero. > > Backend is waiting for the tuples from workers, workers are waiting on > lock of relation. > Attached is the sql script that can reproduce this issue.
Some more tests that failed in similar configuration settings. 1. Table that is created under a begin statement is not visible in the worker. 2. permission problem in worker side for set role command. Regards, Hari Babu Fujitsu Australia
parallel_table_doesn't_exist_problem.sql
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parallel_set_role_permission_problem.sql
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