Re: Lots of stuck queries after upgrade to 9.4 - Mailing list pgsql-general

From Spiros Ioannou
Subject Re: Lots of stuck queries after upgrade to 9.4
Date
Msg-id CACKh8C_AFY5QvG4hwxwLruJQb9f9Q4rV-YijX-k+zYkCvGKX9A@mail.gmail.com
Whole thread Raw
In response to Re: Lots of stuck queries after upgrade to 9.4  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: Lots of stuck queries after upgrade to 9.4
List pgsql-general
Hi Tom,
thank you for your input. The DB was stuck again, I attach all logs and stack traces.

A stack trace from a COMMIT, an INSERT, an UPDATE, the wal writer, the writer, and a sequence.

Stracing the commit was stuck at: semop(3145761, {{12, -1, 0}}, 1

Please tell me what else could I do to help debugging.

Is there a way to downgrade postgresql ?

 

Spiros Ioannou 
IT Manager, inAccess
www.inaccess.com

M: +30 6973-903808
T: +30 210-6802-358


On 20 July 2015 at 01:01, Tom Lane <tgl@sss.pgh.pa.us> wrote:
Spiros Ioannou <sivann@inaccess.com> writes:
> We upgraded to 9.4.4 from 8.4 We have tried 9.3.x in the past with success.
> Unfortunately in 9.4 gets stuck 2-3 times a week.

> Lots of queries seem stuck, that is they have waiting:false. Queries can be
> COMMIT or INSERT.
> No blocking locks seem to exist.
> strace reveals that all stuck processes they are in semop
> semop(2064417, {{0, -1, 0}}, 1^C <unfinished ...>

Stack traces of the stuck processes might help determine what's going on.

https://wiki.postgresql.org/wiki/Generating_a_stack_trace_of_a_PostgreSQL_backend

Please try to capture traces for both the COMMIT and INSERT cases,
as they're almost certainly different.

                        regards, tom lane

Attachment

pgsql-general by date:

Previous
From: Francisco Olarte
Date:
Subject: Re: INSERT ... ON CONFLICT DO UPDATE
Next
From: Alvaro Herrera
Date:
Subject: Re: Lots of stuck queries after upgrade to 9.4