Re: io storm on checkpoints, postgresql 8.2.4, linux

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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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