Date: Tue, 1 Dec 2020 14:38:45 +0100
From: hubert depesz lubaczewski <depesz@depesz.com>
Sender: depesz@depesz.com
To: Walters Che Ndoh <chendohw@gmail.com>
Cc: pgsql-admin@postgresql.org
Subject: Re: killing idle_connections
Message-ID: <20201201133845.GC22431@depesz.com>
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On Mon, Nov 30, 2020 at 07:49:39PM -0700, Walters Che Ndoh wrote:
> I have two DB's in prod
> - DB 1 has pg12 and pgbouncer for connection pooling
> - DB 2 has pg10 and F5 for connection pooling
> 
> Both DB's have a max connection of 500.
> During pick hours i always run out of connections, even though i have 3
> superuser reserved, my connections still go beyond 500.

What is your pool_mode in pgbouncer?
If it's "session" - then it is the problem, and you should consider
reading https://www.depesz.com/2012/12/02/what-is-the-point-of-bouncing/

Please note that not all applications will work OK with transaction
pooling, but if they don't then (for me) it's a sign that they should
get fixed.

depesz