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From: Tom Lane <tgl@sss.pgh.pa.us>
To: neeraj kumar <neeru.cse@gmail.com>
cc: Jeremy Schneider <schnjere@amazon.com>, 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>
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neeraj kumar <neeru.cse@gmail.com> writes:
> Also curious why query on pg_stat_activity is considering terminated
> process ?

The short answer to that is that this bug leaves shared memory in
a corrupt state.  It's not really useful to worry about whether
readers should react differently to that --- you could spend endless
amounts of time hypothesizing different kinds of corruption and
endless amounts of code/cycles trying to work around it.  But the
right answer is to fix it on the writing side.

			regards, tom lane