Re: Latency tests with 2.6.12-rc1

Lee Revell
2005-03-23T22:13:08Z

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On Tue, 2005-03-22 at 09:22 +0100, Ingo Molnar wrote:
> hm, weird, and i have no solution for this yet. But i just found a
> related bug in the -RT patch in that it reverted a latency breaker in
> the ext3 path that your trace shows - affecting PREEMPT_DESKTOP. Could
> you try the 40-03 patch i just uploaded (assuming it's stable for you
> otherwise ...) and see whether you can still reproduce these latencies?
> (if yes then please also send me a full trace via private mail, or bzip
> -9 it in your public mail.)

Ingo,

The problem is fixed. Now the longest latency I see with "dbench 16"
and PREEMPT_DESKTOP is 591us in the ext3 reservation code. Trace is
attached (compressed) in case anyone is interested. But I do not
consider anything under a millisecond to be a problem with
PREEMPT_DESKTOP.

Lee

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