Messages in this thread | | | Date | Mon, 24 Sep 2012 19:46:19 +0530 | From | Raghavendra K T <> | Subject | Re: [PATCH RFC 0/2] kvm: Improving undercommit,overcommit scenarios in PLE handler |
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On 09/24/2012 07:24 PM, Peter Zijlstra wrote: > On Mon, 2012-09-24 at 18:59 +0530, Raghavendra K T wrote: >> However Rik had a genuine concern in the cases where runqueue is not >> equally distributed and lockholder might actually be on a different run >> queue but not running. > > Load should eventually get distributed equally -- that's what the > load-balancer is for -- so this is a temporary situation. > > We already try and favour the non running vcpu in this case, that's what > yield_to_task_fair() is about. If its still not eligible to run, tough > luck.
Yes, I agree.
> >> Do you think instead of using rq->nr_running, we could get a global >> sense of load using avenrun (something like avenrun/num_onlinecpus) > > To what purpose? Also, global stuff is expensive, so you should try and > stay away from it as hard as you possibly can.
Yes, that concern only had made me to fall back to rq->nr_running.
Will come back with the result soon.
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