PE2950, LSI SAS -> SATA very slow
adam.nielsen at uq.edu.au
Mon May 3 20:40:08 CDT 2010
> I've seen flaky/unpredictable performance with these LSI controllers.
> Also some Seagate 1TB drives have performance bugs which affect
> sequential reads - so you could try using alternative drive firmwares,
> as the bug seems to have been fixed in the non-Dell firmware (see my
> recent posts to this list - still no response from Dell on this issue!).
I just looked at the site in your post to the other thread and sure
enough, these disks are ST31000340NS, although they are only running
MA08 (the firmware released to stop them from dying after shutdown.)
Still, given that they top out at just over 50MB/sec with sequential
reads it would seem that they are affected by the issue. I've asked our
account manager when updated firmware will be released to fix the issue,
so I'll post again when I hear back.
I'm a bit reluctant to flash non-Dell firmware as it's a production
machine and I might need Dell support on it, but I'll try the NCQ fix
and see if it helps in the mean time.
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