Re: Integrated perc 5/i - Mailing list pgsql-performance

From Merlin Moncure
Subject Re: Integrated perc 5/i
Date
Msg-id b42b73150708160559h18502bb9ved421ec4b7be7c1a@mail.gmail.com
Whole thread Raw
In response to Integrated perc 5/i  ("Michael Ben-Nes" <miki@epoch.co.il>)
List pgsql-performance
On 8/16/07, Michael Ben-Nes <miki@epoch.co.il> wrote:
> Hi
>
> I wanted to know if the integrated perc 5/i which come with Dell 2950 will
> yield maximum performance from RAID 10 ( 15K SAS ).
> Or should I ask for different card ?
>
> I read an old post that shows that RAID 10 does not work eficently under
> perc 5/i
>
http://groups.google.com/group/pgsql.performance/browse_thread/thread/b85926fe6de1f6c2/38837995887b6033?lnk=st&q=perc+5%2Fi+performance&rnum=6&hl=en#38837995887b6033
>
> Does any one have any experience with RAID 10 & perc 5/i ?

no, I've tested raid 10 on a few different perc 5/i and never had
those results. raid 10 often gives poor sequential read performance
relative to a raid 5 but better random performance generally, which is
usually more important.  That said, the perc 5/e (never done raid 5 on
the 5/i) has posted some of the best raid 5 numbers I've ever seen in
terms of random performance on sata.

merlin

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