Messages in this thread | | | Date | Tue, 23 Jul 2013 14:05:01 +0200 | From | Peter Zijlstra <> | Subject | Re: [RFC PATCH v2] sched: Limit idle_balance() |
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On Tue, Jul 23, 2013 at 04:36:46PM +0530, Srikar Dronamraju wrote:
> May be the current max value is a limiting factor, but I think there > should be a limit to the maximum value. Peter and Ingo may help us > understand why they limited to the 1ms. But I dont think we should > introduce a new variable just for this.
/me blames it all on Mike.. I tried to remember why he did that, but alas.
> If idle balance did succeed, then it means that the system was indeed > imbalanced. So idle balance was the right thing to do. May be we chose > the wrong task to pull. May be after numa balancing enhancements go in, > we pick a better task to pull atleast across nodes. And there could be > other opportunities/strategies to select a right task to pull. > > Again, schedstats during the application run should give us hints here.
Not necessarily so, IIRC the newidle idx is 0 which means that its very aggressive at pulling load, there might not actually be an imbalance with higher idx averages.
> I was saying it the other way. > your suggestion is to run idle balance once in n runs .. where n is 10 > to 20. > My thinking was to not run idle balance once in n unsuccessful runs.
I think you're talking past each other. Each having a different N :-)
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