From: Tom Lane <tgl@sss.pgh.pa.us>
To: neeraj kumar <neeru.cse@gmail.com>
cc: pgsql-admin@postgresql.org, pgsql-general@postgresql.org
Subject: Re: Query on pg_stat_activity table got stuck
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Comments: In-reply-to neeraj kumar <neeru.cse@gmail.com>
	message dated "Mon, 06 May 2019 11:24:31 -0700"
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Date: Mon, 06 May 2019 17:33:06 -0400
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neeraj kumar <neeru.cse@gmail.com> writes:
> We are using PG 10.6. We have one cron job that queries pg_stat_activity
> table to find out how many queries are running longer than X minutes and
> generate metrics.

> Query look like this :
> SELECT * FROM pg_stat_activity WHERE state=3D'active'

> After some days, this query get stuck and doesn't finish. We tried to ru=
n
> this query manually and same result.

> We looked into pg_locks table and there this query is not blocked on any
> lock :
> https://justpaste.it/48rpe

Interesting.  Can you get a stack trace to show where in the code it's
stuck?

https://wiki.postgresql.org/wiki/Generating_a_stack_trace_of_a_PostgreSQL_=
backend

			regards, tom lane