Re: performance drop on RAID5

From: Frank Wiles
Subject: Re: performance drop on RAID5
Date: ,
Msg-id: 20050824105243.067f0ae5.frank@wiles.org
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In response to: performance drop on RAID5  (Alexandre Barros)
List: pgsql-performance

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performance drop on RAID5  (Alexandre Barros, )
 Re: performance drop on RAID5  (Frank Wiles, )
 Re: performance drop on RAID5  (Arjen van der Meijden, )
 Re: performance drop on RAID5  (Rosser Schwarz, )
 Re: performance drop on RAID5  ("Joshua D. Drake", )
 Re: performance drop on RAID5  ("Merlin Moncure", )

On Wed, 24 Aug 2005 11:43:05 -0300
Alexandre Barros <> wrote:

> I've googled a little, and maybe the cluster size might be one
> problem,  but despite that, the performance dropping when running on
> "server-class" hardware with RAID-5 SCSI-2 drives was way above my
> most  delirious expectations... i need some help to figure out what is
> **so**  wrong...

  RAID-5 isn't great for databases in general.  What would be better
  would be to mirror the disks to redundancy or do RAID 1+0.

  You could probably also increase your shared_buffers some, but
  that alone most likely won't make up your speed difference.

 ---------------------------------
   Frank Wiles <>
   http://www.wiles.org
 ---------------------------------



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