Simon Banton wrote:
At 09:24 -0400 2/10/07, Ross S. W. Walker wrote:
Actually the real-real fix was to use the 'deadline' or
'noop' scheduler
with this card as the default 'cfq' scheduler was designed
to work with
a single drive and not a multiple drive RAID, so it acts as
a govenor on
the amount of IO that a single process can send to the
device and when
you do multiple overlapping IOs performance decreases instead of increases.
Ah - that wasn't actually a complete fix Ross, but it did give a noticeable improvement in certain situations. I'm still chasing a real real 'general purpose' fix.
I was unaware of that. I thought changing schedulers did it.
What is the recurring performance problem you are seeing?
-Ross
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