On Mon, Aug 11, 2008 at 6:08 AM, Henrik <henke@xxxxxx> wrote: > 11 aug 2008 kl. 12.35 skrev Glyn Astill: > >>>> >>>>> It feels like there is something fishy going on. >>> >>> Maybe the RAID 10 >>>>> >>>>> implementation on the PERC/6e is crap? >>>> >> >> It's possible. We had a bunch of perc/5i SAS raid cards in our servers >> that performed quite well in Raid 5 but were shite in Raid 10. I switched >> them out for Adaptec 5808s and saw a massive improvement in Raid 10. > > I suspected that. Maybe I should just put the PERC/6 cards in JBOD mode and > then make a RAID10 with linux software raid MD? You can also try making mirror sets with the hardware RAID controller and then doing SW RAID 0 on top of that. Since RAID0 requires little or no CPU overhead, this is a good compromise because the OS has the least work to do, and the RAID controller is doing what it's probably pretty good at, mirror sets.
