From: mark@mark.mielke.cc
To: Luke Lonergan <llonergan@greenplum.com>
Cc: Bucky Jordan <bjordan@lumeta.com>
Cc: Spiegelberg, Greg <gspiegelberg@cranel.com>
Cc: Joshua Drake <jd@commandprompt.com>
Cc: Craig A. James <cjames@modgraph-usa.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: Large tables (was: RAID 0 not as fast as expected)
Date: Mon, 18 Sep 2006 23:45:47 -0400
Message-ID: <20060919034547.GA24692@mark.mielke.cc> (raw)
In-Reply-To: <C1349185.316F4%llonergan@greenplum.com>
References: <78ED28FACE63744386D68D8A9D1CF5D42099C7@MAIL.corp.lumeta.com>
<C1349185.316F4%llonergan@greenplum.com>
On Mon, Sep 18, 2006 at 06:10:13PM -0700, Luke Lonergan wrote:
> Also be sure to set the random_page_cost parameter in
> postgresql.conf to 100 or even higher when you use indexes, as the actual
> seek rate for random access ranges between 50 and 300 for modern disk
> hardware. If this parameter is left at the default of 4, indexes will often
> be used inappropriately.
Does a tool exist yet to time this for a particular configuration?
Cheers,
mark
--
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To: pgsql-performance@postgresql.org
Cc: mark@mark.mielke.cc, llonergan@greenplum.com, bjordan@lumeta.com, gspiegelberg@cranel.com, jd@commandprompt.com, cjames@modgraph-usa.com
Subject: Re: Large tables (was: RAID 0 not as fast as expected)
In-Reply-To: <20060919034547.GA24692@mark.mielke.cc>
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