From: Joshua D. Drake <jd@commandprompt.com>
To: Dmitry Potapov <fortune.fish@gmail.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: io storm on checkpoints, postgresql 8.2.4, linux
Date: Wed, 22 Aug 2007 09:01:43 -0700
Message-ID: <46CC5DE7.9010201@commandprompt.com> (raw)
In-Reply-To: <878c83960708220833l72dbd461k827aea77ec7d6c32@mail.gmail.com>
References: <878c83960708220833l72dbd461k827aea77ec7d6c32@mail.gmail.com>
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Dmitry Potapov wrote:
> Hello!
>
> We run a large (~66Gb) web-backend database on Postgresql 8.2.4 on
> Linux. The hardware is Dual Xeon 5130 with 16Gb ram, LSI Megaraid U320-2x
> scsi controller w/512Mb writeback cache and a BBU. Storage setup contains 3
> raid10 arrays (data, xlog, indexes, each on different array), 12 HDDs total.
> Frontend application uses jdbc driver, connection pooling and threads.
>
> We've run into an issue of IO storms on checkpoints. Once in 20min
> (which is checkpoint_interval) the database becomes unresponsive for about
> 4-8 seconds. Query processing is suspended, server does nothing but writing
What are your background writer settings?
Joshua D. Drake
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To: pgsql-performance@postgresql.org
Cc: jd@commandprompt.com, fortune.fish@gmail.com
Subject: Re: io storm on checkpoints, postgresql 8.2.4, linux
In-Reply-To: <46CC5DE7.9010201@commandprompt.com>
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