Messages in this thread | | | Subject | Re: [PATCH] sched: wake-affine throttle | From | Mike Galbraith <> | Date | Thu, 11 Apr 2013 10:44:22 +0200 |
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On Thu, 2013-04-11 at 16:26 +0800, Michael Wang wrote:
> The 1:N is a good reason to explain why the chance that wakee's hot data > cached on curr_cpu is lower, and since it's just 'lower' not 'extinct', > after the throttle interval large enough, it will be balanced, this > could be proved, since during my test, when the interval become too big, > the improvement start to drop.
Magnitude of improvement drops just because there's less damage done methinks. You'll eventually run out of measurable damage :)
Yes, it's not really extinct, you _can_ reap a gain, it's just not at all likely to work out. A more symetric load will fare better, but any 1:N thing just has to spread far and wide to have any chance to perform. > Hmm...that's an interesting point, the workload contain different > 'priority' works, and depend on each other, if mother starving, all the > kids could do nothing but wait for her, may be that's the reason why the > benefit is so significant, since in such case, mother's little quicker > respond will make all the kids happy :)
Exactly. The entire load is server latency bound. Keep the server on cpu, the load performs as best it can given unavoidable data miss cost.
-Mike
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