From: Simon Riggs <simon@2ndquadrant.com>
To: josh@agliodbs.com
Cc: pgsql-performance@postgresql.org
Subject: Re: 2GB or not 2GB
Date: Sat, 31 May 2008 08:44:57 +0100
Message-ID: <1212219897.4120.195.camel@ebony.site> (raw)
In-Reply-To: <200805281659.26945.josh@agliodbs.com>
References: <200805281659.26945.josh@agliodbs.com>
On Wed, 2008-05-28 at 16:59 -0700, Josh Berkus wrote:
> sort_mem: My tests with 8.2 and DBT3 seemed to show that, due to
> limitations of our tape sort algorithm, allocating over 2GB for a single
> sort had no benefit. However, Magnus and others have claimed otherwise.
> Has this improved in 8.3?
There is an optimum for each specific sort.
Your results cannot be used to make a global recommendation about the
setting of work_mem. So not finding any benefit in your tests *and*
Magnus seeing an improvement are not inconsistent events.
--
Simon Riggs www.2ndQuadrant.com
PostgreSQL Training, Services and Support
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To: pgsql-performance@postgresql.org
Cc: simon@2ndquadrant.com, josh@agliodbs.com
Subject: Re: 2GB or not 2GB
In-Reply-To: <1212219897.4120.195.camel@ebony.site>
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