Re: [HACKERS] Weaker shmem interlock w/o postmaster.pid - Mailing list pgsql-hackers

From Thomas Munro
Subject Re: [HACKERS] Weaker shmem interlock w/o postmaster.pid
Date
Msg-id CA+hUKGKZncyFcQ95VQOXiTBPiyxhiJ-9YKTso=SHMQikyKhJyg@mail.gmail.com
Whole thread Raw
In response to Re: [HACKERS] Weaker shmem interlock w/o postmaster.pid  (Noah Misch <noah@leadboat.com>)
Responses Re: [HACKERS] Weaker shmem interlock w/o postmaster.pid
List pgsql-hackers
On Mon, Apr 8, 2019 at 6:42 PM Noah Misch <noah@leadboat.com> wrote:
> - lorikeet's FailedAssertion("!(vmq->mq_sender == ((void *)0))" looked
>   suspicious, but this happened six other times in the past year[2], always on
>   v10 lorikeet.

It happens on v11 too:

https://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=lorikeet&dt=2018-09-25%2010%3A06%3A31

The text changed slightly because we dropped an unnecessary extra
pointer-to-volatile:

FailedAssertion("!(mq->mq_sender == ((void *)0))"

So either two workers started with the same parallel worker number, or
something unexpectedly overwrote the shm_mq struct?

-- 
Thomas Munro
https://enterprisedb.com



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