Scott Marlowe schrieb:
On Tue, Dec 2, 2008 at 2:22 AM, Mario Weilguni <mweilguni@xxxxxxxx> wrote:
Has anyone benchmarked this controller (PCIe/4x, 512 MB BBC)? We try to use
it with 8x SATA 1TB drives in RAID-5 mode under Linux, and measure strange
values. An individual drive is capable of delivering 91 MB/sec sequential
read performance, and we get values ~102MB/sec out of a 8-drive RAID5, seems
to be ridiculous slow. Write performance seems to be much better, ~300 MB
/sec - seems ok to me.
I guess I must be doing something wrong, I cannot believe that a 500 €
controller is delivering such poor performance.
A few suggestions... Try to find the latest driver for your card, try
using the card as nothing but a caching controller and run your RAID
on software in linux (or whatever IS you're on). Test a 2 drive
RAID-0 to see what kind of performance increase you get. If you can't
dd a big file off of a RAID-0 at about 2x the rate of a single drive
then something IS wrong with it. Try RAID 10. Try RAID-1 sets on the
controller and RAID 0 over that in software.
I've already tried Softraid with individual drives, performs much
better. However, it's no option to use softraid, so I'm stuck. The card
has the latest firmware installed, and there are no drivers needed,
they're already included in the linux kernel.
I still think we must be doing something wrong here, I googled the
controller and Linux, and did not find anything indicating a problem.
The HP SmartArray series is quite common, so a lot of users would have
the same problem.
Thanks!
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