Re: BUG #15036: Un-killable queries Hanging in BgWorkerShutdown

AMANHÃ BEREMOS

Em 07/02/2018 8:35 PM, "Thomas Munro" <thomas(dot)munro(at)enterprisedb(dot)com>
escreveu:

> On Thu, Feb 8, 2018 at 7:06 AM, David Kohn <djk447(at)gmail(dot)com> wrote:
> > I'm not clear on when we do a SetLatch on those message queues during a
> > cancel of parallel workers, and a number of other things that could
> > definitely invalidate this analysis, but I think there could be a
> plausible
> > explanation in there somewhere.
>
> shm_mq_detach_internal() does SetLatch(&victim->procLatch) ("victim"
> being the counterparty process) after setting mq_detached. So ideally
> no one should ever be able to wait forever on a queue from which the
> other end has detached, but perhaps there is some race condition style
> bug lurking in here. I'm going to do some testing and see if I can
> break this...
>
> > Thanks for the help on this, I hope this is helpful and do let me know
> if a
> > stacktrace or anything else would be helpful on my end.
>
> Yeah stack traces would be great, if you can.
>
> --
> Thomas Munro
> http://www.enterprisedb.com
>
>