Re: Hardware suggestions for high performance 8.3 - Mailing list pgsql-performance

From Henrik
Subject Re: Hardware suggestions for high performance 8.3
Date
Msg-id E8D1FB0E-93EE-42D4-BD06-19CB87E21494@mac.se
Whole thread Raw
In response to Re: Hardware suggestions for high performance 8.3  (Greg Smith <gsmith@gregsmith.com>)
Responses Re: Hardware suggestions for high performance 8.3
List pgsql-performance
I've seen some concerns about buying database performance hardware
from DELL. Are there at least some of the RAID cards that work well
with Linux or should I stay clear of DELL permanently?

Thanks!

//Henke
25 jun 2008 kl. 17.45 skrev Greg Smith:

> On Wed, 25 Jun 2008, Henrik wrote:
>
>> Would you turn off fsync if you had a controller with BBU? =)
>
> Turning off fsync has some potential to introduce problems even in
> that environment, so better not to do that.  The issue is that you
> might have, say, 1GB of OS-level cache but 256MB of BBU cache, and
> if you turn fsync off it won't force the OS cache out to the
> controller when it's supposed to and that can cause corruption.
>
> Also, if you've got a controller with BBU, the overhead of fsync for
> regular writes is low enough that you don't really need to turn it
> off. If writes are cached the fsync is almost free.
>
> --
> * Greg Smith gsmith@gregsmith.com http://www.gregsmith.com
> Baltimore, MD
>
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