On Mon, 2006-12-04 at 01:17, Alex Turner wrote: > People recommend LSI MegaRAID controllers on here regularly, but I > have found that they do not work that well. I have bonnie++ numbers > that show the controller is not performing anywhere near the disk's > saturation level in a simple RAID 1 on RedHat Linux EL4 on two > seperate machines provided by two different hosting companies. In one > case I asked them to replace the card, and the numbers got a bit > better, but still not optimal. > > LSI MegaRAID has proved to be a bit of a disapointment. I have seen > better numbers from the HP SmartArray 6i, and from 3ware cards with > 7200RPM SATA drives. > > for the output: http://www.infoconinc.com/test/bonnie++.html (the > first line is a six drive RAID 10 on a 3ware 9500S, the next three are > all RAID 1s on LSI MegaRAID controllers, verified by lspci). Wait, you're comparing a MegaRAID running a RAID 1 against another controller running a 6 disk RAID10? That's hardly fair. My experience with the LSI was that with the 1.18 series drivers, they were slow but stable. With the version 2.x drivers, I found that the performance was very good with RAID-5 and fair with RAID-1 and that layered RAID was not any better than unlayered (i.e. layering RAID0 over RAID1 resulted in basic RAID-1 performance). OTOH, with the choice at my last place of employment being LSI or Adaptec, LSI was a much better choice. :) I'd ask which LSI megaraid you've tested, and what driver was used. Does RHEL4 have the megaraid 2 driver?
