From: Josh Berkus <josh@agliodbs.com>
To: Anish Kejariwal <anishkej@gmail.com>
Cc: Jeff Janes <jeff.janes@gmail.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: Expected performance of querying 5k records from 4 million records?
Date: Mon, 18 Jun 2012 12:08:37 -0700
Message-ID: <4FDF7CB5.4060207@agliodbs.com> (raw)
In-Reply-To: <CAOpcnr9MOa_CbB7pLOOry_710F4F27zeXjXqSYbf7kKvx5owwg@mail.gmail.com>
References: <CAOpcnr8S2hmV1z-=ZF1k+t+uWWyw82nUbwhpQmdf=8R_Kpv78g@mail.gmail.com>
<CAMkU=1zn+Z9iw96nEqJjqSzysv53DT8Y0Kba2GTw9a9qHtEC6w@mail.gmail.com>
<CAOpcnr9MOa_CbB7pLOOry_710F4F27zeXjXqSYbf7kKvx5owwg@mail.gmail.com>
On 6/18/12 9:39 AM, Anish Kejariwal wrote:
> Thanks for the help, Jeff and Josh. It looks reclustering the multi-column
> index might solve things. For my particular query, because I'm getting a
> range of records back, it makes sense that reclustering will benefit me if
> I have a slow disk even if I had expected that the indices would be
> sufficient . I now need to make sure that the speed up I'm seeing is not
> because things have been cached.
Well, other than that your performance is as expected because of your
much-larger-than-RAM database and your relatively slow disk.
--
Josh Berkus
PostgreSQL Experts Inc.
http://pgexperts.com
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To: pgsql-performance@postgresql.org
Cc: josh@agliodbs.com, anishkej@gmail.com, jeff.janes@gmail.com
Subject: Re: Expected performance of querying 5k records from 4 million records?
In-Reply-To: <4FDF7CB5.4060207@agliodbs.com>
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