Messages in this thread | | | Subject | Re: [PATCH 0/4] Finer granularity and task/cgroup irq time accounting | From | Peter Zijlstra <> | Date | Tue, 24 Aug 2010 13:53:55 +0200 |
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On Tue, 2010-08-24 at 17:08 +0530, Balbir Singh wrote: > > The point is for containers it is more likely to give the right answer > and so on. Yes, the results are not 100% accurate.
Consider one group heavily dirtying pages, it stuffs the IO queues full and gets blocked on IO completion. Since the CPU is then free to schedule something else we start running things from another group, those IO completions will come in while we run other group and get accounted to other group -- FAIL.
s/group/task/ etc..
That just really doesn't work, accounting async work, esp stuff that is not under software control it very tricky indeed.
So what are you wanting to do, and why. Do you really need accounting madness?
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