Date: Tue, 12 Mar 2019 15:11:02 -0500
From: Justin Pryzby <pryzby@telsasoft.com>
To: MichaelDBA <MichaelDBA@sqlexec.com>
Cc: Michael Lewis <mlewis@entrata.com>,
	Laurenz Albe <laurenz.albe@cybertec.at>,
	Daulat Ram <Daulat.Ram@exponential.com>,
	"pgsql-performance@lists.postgresql.org"
 <pgsql-performance@lists.postgresql.org>
Subject: Re: Shared_buffers
Message-ID: <20190312201102.GI23597@telsasoft.com>
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On Tue, Mar 12, 2019 at 04:03:11PM -0400, MichaelDBA wrote:
> Set shared_buffers more accurately by using pg_buffercache extension and the
> related queries during high load times.

I've tuned ~40 postgres instances, primarily using log_checkpoints and
pg_stat_bgwriter, with custom RRD graphs.  pg_buffercache does provide some
valuable insights, and I know it's commonly suggested to check histogram of
usagecounts, but I've never had any idea how to apply that to tune
shared_buffers.

Could you elaborate on what procedure you suggest ?

Justin