Re: [PATCH] locking/mutex: Avoid spinner vs waiter starvation

From	huang ying <huang.ying.caritas@gmail.com>
Newsgroups	linux.kernel
Subject	Re: [PATCH] locking/mutex: Avoid spinner vs waiter starvation
Date	2016-02-04 10:00 +0100
Message-ID	<qYnVF-6fU-13@gated-at.bofh.it> (permalink)
References	(7 earlier) <qUnUd-1Ui-1@gated-at.bofh.it> <qWe0r-OA-19@gated-at.bofh.it> <qWsmK-3ln-5@gated-at.bofh.it> <qXjAL-11X-7@gated-at.bofh.it> <qYh3P-1Sf-9@gated-at.bofh.it>
Organization	linux.* mail to news gateway

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Hi, Low,

On Thu, Feb 4, 2016 at 9:35 AM, Jason Low <jason.low2@hp.com> wrote:
> I've done some testing with this patch with some of the AIM7 workloads
> and found that this reduced throughput by about 10%. The reduction in
> throughput is expected since spinning as a waiter is less efficient.
>
> Another observation I made is that the top waiter spinners would often
> times require needing to reschedule before being able to acquire the
> lock from spinning when there was high contention. A waiter can go into
> the cycle of spin -> reschedule -> spin -> reschedule. So although the
> chance of starvation is reduced, this patch doesn't fully address the
> issue of waiter starvation.

Could you share your workload?  I want to reproduce it in 0day/LKP+ environment.

Best Regards,
Huang, Ying

Thread

Re: [PATCH RFC] locking/mutexes: don't spin on owner when wait list  is not NULL. Peter Zijlstra <peterz@infradead.org> - 2016-01-29 11:00 +0100
  Re: [PATCH RFC] locking/mutexes: don't spin on owner when wait list  is not NULL. Ding Tianhong <dingtianhong@huawei.com> - 2016-01-30 02:20 +0100
    Re: [PATCH RFC] locking/mutexes: don't spin on owner when wait list  is not NULL. huang ying <huang.ying.caritas@gmail.com> - 2016-02-01 04:30 +0100
      Re: [PATCH RFC] locking/mutexes: don't spin on owner when wait list is not NULL. "Huang\, Ying" <ying.huang@intel.com> - 2016-02-01 04:40 +0100
    [PATCH] locking/mutex: Avoid spinner vs waiter starvation Peter Zijlstra <peterz@infradead.org> - 2016-02-01 11:10 +0100
      Re: [PATCH] locking/mutex: Avoid spinner vs waiter starvation Davidlohr Bueso <dave@stgolabs.net> - 2016-02-02 22:20 +0100
        Re: [PATCH] locking/mutex: Avoid spinner vs waiter starvation Ding Tianhong <dingtianhong@huawei.com> - 2016-02-03 08:20 +0100
          Re: [PATCH] locking/mutex: Avoid spinner vs waiter starvation Davidlohr Bueso <dave@stgolabs.net> - 2016-02-03 20:30 +0100
            Re: [PATCH] locking/mutex: Avoid spinner vs waiter starvation Ding Tianhong <dingtianhong@huawei.com> - 2016-02-04 02:30 +0100
        Re: [PATCH] locking/mutex: Avoid spinner vs waiter starvation Waiman Long <waiman.long@hpe.com> - 2016-02-03 23:10 +0100
      Re: [PATCH] locking/mutex: Avoid spinner vs waiter starvation Jason Low <jason.low2@hp.com> - 2016-02-04 02:40 +0100
        Re: [PATCH] locking/mutex: Avoid spinner vs waiter starvation huang ying <huang.ying.caritas@gmail.com> - 2016-02-04 10:00 +0100
          Re: [PATCH] locking/mutex: Avoid spinner vs waiter starvation Jason Low <jason.low2@hp.com> - 2016-02-05 00:00 +0100

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