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Date: Wed, 17 Jul 2019 13:55:51 -0400
From: Alvaro Herrera <alvherre@2ndquadrant.com>
To: Justin Pryzby <pryzby@telsasoft.com>
Cc: Hugh Ranalli <hugh@whtc.ca>, pgsql-performance@lists.postgresql.org
Subject: Re: Perplexing, regular decline in performance
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On 2019-Jun-26, Justin Pryzby wrote:

> > Also, Should pg_buffercache perhaps be run at the beginning and end of the
> > week, to see if there is a significant difference?
> 
> Yes; buffercache can be pretty volatile, so I'd save it numerous times each at
> beginning and end of week.

Be careful with pg_buffercache though, as it can cause a hiccup in
operation.

-- 
Álvaro Herrera                https://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services