Re: RAID5 chunksize?

[Jakob Oestergaard]

On Tue, Dec 10, 2002 at 10:23:30AM -0500, Robert L. Harris wrote:
> 
> 
> Ok, say I'm building a 4 disk raid5 array.  Performance is going to be
> critical as this system is going to be very IO intensive.  We had to go
> RAID5 though due to filesystem requirements.
> 
> According to the manufacturer the disks have:
> 
>   8Meg DataBuffer
>   10K RPM Rotational speed
>   SCSI Ultra 160
> 
> (Drive is:
> http://www.fel.fujitsu.com/home/product.asp?L=en&PID=248&INFO=fsp)
> 
> What is the ideal Chunksize?  

Measure.

Try 4k, 32k, 128k, and see which is best.

Please post the results to the list  :)

It is important that you benchmark not with tiotest or bonnie, but with
the actual applications that need to use this server.

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