| From | Vincent Guittot <> | Date | Thu, 10 Jul 2014 16:03:51 +0200 | Subject | Re: [PATCH v3 08/12] sched: move cfs task on a CPU with higher capacity |
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On 10 July 2014 13:18, Peter Zijlstra <peterz@infradead.org> wrote: > On Mon, Jun 30, 2014 at 06:05:39PM +0200, Vincent Guittot wrote: >> + /* >> + * If the CPUs share their cache and the src_cpu's capacity is >> + * reduced because of other sched_class or IRQs, we trig an >> + * active balance to move the task >> + */ >> + if ((sd->flags & SD_SHARE_PKG_RESOURCES) >> + && ((capacity_orig_of(src_cpu) * 100) > (capacity_of(src_cpu) * >> + sd->imbalance_pct))) >> return 1; > > Why is this tied to shared caches?
It's just to limit the change of the policy to a level that can have benefit without performance regression. I'm not sure that we can do that at any level without risk
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