>>>>> "Kai" == Kai Leibrandt <k_leibrandt@xxxxxxxxxxx> writes:
Kai> Dragos' question about the su,sw options led me to have another
Kai> look at my Mylex RAID setup, and I now am confused too... My
Kai> RAID controller tells me that the primary RAID volume (a 3-disk
Kai> RAID 5) has a Stripe Size of 64k and a Segment Size of 8k. So for
Kai> this setup should the sunit be set to 64k or to 8k (the segment
Kai> size)??? The manual fo the DAC says that the segment size is the
Kai> preferred io size for caching, but xfs has a preferred io size
Kai> equal to the stripe size - which to choose?
Hmmm. My guess would be that the Mylex uses 8k hardware sectors
internally and does read/modify/write on those.
Whether the 64K is stripe width or stripe unit, I don't know.
The real answer is the same as always: Try both settings with your
anticipated I/O load and see which one performs better.
--
Martin K. Petersen http://mkp.net/
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