From: Jeff Janes <jeff.janes@gmail.com>
To: Kevin Grittner <Kevin.Grittner@wicourts.gov>
Cc: Grant Masan <grant.massan@gmail.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: Problem with database performance, Debian 4gb ram ?
Date: Tue, 3 Nov 2009 09:23:33 -0800
Message-ID: <f67928030911030923i31663c7ew8d75b04874cb568d@mail.gmail.com> (raw)
In-Reply-To: <4AEFF447020000250002C19D@gw.wicourts.gov>
References: <c09b5d640911020616t7177a7b9sb4b5f285d99e7c05@mail.gmail.com>
<4AEFF447020000250002C19D@gw.wicourts.gov>
On Tue, Nov 3, 2009 at 7:13 AM, Kevin Grittner
<Kevin.Grittner@wicourts.gov> wrote:
> Grant Masan <grant.massan@gmail.com> wrote:
>
>
>> cpu_tuple_cost = 0.0030
>> cpu_index_tuple_cost = 0.0010
>> cpu_operator_cost = 0.0005
>
> Why did you make these adjustments? I usually have to change the
> ratio between page and cpu costs toward the other direction.
Is that because the database is mostly cached in memory? If I take the
documented descriptions of the costs parameters at face value, I find
that cpu_tuple_cost should be even lower yet.
Cheer,
Jeff
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To: pgsql-performance@postgresql.org
Cc: jeff.janes@gmail.com, Kevin.Grittner@wicourts.gov, grant.massan@gmail.com
Subject: Re: Problem with database performance, Debian 4gb ram ?
In-Reply-To: <f67928030911030923i31663c7ew8d75b04874cb568d@mail.gmail.com>
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