On Tue, 6 May 2008, Craig James wrote:
> I/O Sched AVG Test1 Test2
> --------- ----- ----- -----
> cfq 705 695 715
> noop 758 769 747
> deadline 741 705 775
> anticipatory 494 477 511
Interesting. That contrasts with some tests I did a while back on a
16-disc RAID-0, where noop, deadline, and anticipatory were all identical
in performance, with cfq being significantly slower. Admittedly, the disc
test was single-process, which is probably why the anticipatory behaviour
didn't kick in. You are seeing a little bit of degradation with cfq - I
guess it's worse the bigger the disc subsystem you have.
Matthew
--
Matthew: That's one of things about Cambridge - all the roads keep changing
names as you walk along them, like Hills Road in particular.
Sagar: Yes, Sidney Street is a bit like that too.
Matthew: Sidney Street *is* Hills Road.
