Redundant NFS storage setup (part 3) : The disappointing PERC5/E

[Matthias Saou]

Jimmy Christensen wrote :

> I would suggest testing with a stripe size of 64kb instead of 128kb. We 
> are currently testing our HP servers with a P800 with similar 
> dissapointment, but found out that anything above a stripe size of 64kb 
> absolutely kills the performance (ofcourse no one would tell us that). I 
> believe it's based on a similar chip that the PERC5/E has.

I've just tested with 64k stripe size. Read speed is still
disappointingly low... 50-60MB/s where software RAID gives 310-330MB/s.

It seems like this is even less than with 128k stripe size, with a
single non-cached file read I get 80-110MB/s now, had up to 250MB/s
with 128k stripe size and... 320MB/s with software RAID.

But to be 100% sure, I need to wait for the background initialization
to finish, which will take a few hours. I'm not holding my breath,
though.

Matthias

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