From: Josh Close <narshe@gmail.com>
To: POSTGRES-PERFORMANCE <pgsql-performance@postgresql.org>
Subject: Re: slow queries, possibly disk io
Date: Fri, 27 May 2005 07:52:16 -0500
Message-ID: <4a0cafe205052705526fccfe75@mail.gmail.com> (raw)
In-Reply-To: <42963C3F.4000905@arbash-meinel.com>
References: <4a0cafe205052613242e0d4d10@mail.gmail.com>
<42963C3F.4000905@arbash-meinel.com>
> Setting shared buffers above something like 10-30% of memory is counter
> productive.
What is the reason behind it being counter productive? If shared
buffers are at 30%, should effective cache size be at 70%? How do
those two relate?
>
> Increasing sort_mem can help with various activities, but increasing it
> too much can cause you to swap, which kills performance. The caution is
> that you will likely use at least 1 sort_mem per connection, and can
> likely use more than one if the query is complicated.
I have a max of 100 connections and 2 gigs of mem. Right now the sort
mem is a 4 megs. How much higher could I put that?
-Josh
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To: pgsql-performance@postgresql.org
Cc: narshe@gmail.com
Subject: Re: slow queries, possibly disk io
In-Reply-To: <4a0cafe205052705526fccfe75@mail.gmail.com>
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