Re: Debugging a backend stuck consuming CPU

On 05/19/2016 06:46 AM, ktm(at)rice(dot)edu wrote:
> Hi PostgreSQL community,
>
> I am investigating a problem with a backend that appears to be stuck
> and spinning while performing a "DISCARD ALL" command. The system is
> running an older release 9.2.2. Are there any bugs that could be
> causing this behavior? How can I tell what the process is actually
> doing? It does not respond to either pg_cancel_backend() or to
> pg_terminate_backend() so it is acting like it is not receiving the
> signals. Any ideas on how to debug this would be appriciated.

What does the Postgres log show around the time of the command and/or
currently?

What OS and does it's system log show anything?

Can you query pg_stat_activity?

http://www.postgresql.org/docs/9.2/static/monitoring-stats.html#PG-STAT-ACTIVITY-VIEW

>
> Regards,
> Ken
>
>

--
Adrian Klaver
adrian(dot)klaver(at)aklaver(dot)com