Re: [PATCH v2 0/4] locking/mutex: Enable optimistic spinning of lock waiter

From: Peter Zijlstra
Date: Tue Feb 16 2016 - 03:51:21 EST


On Fri, Feb 12, 2016 at 12:32:11PM -0500, Waiman Long wrote:
> My own test on a 4-socket E7-4820 v3 system showed a regression of
> about 4% in the high_systime workload with Peter's patch which this
> new patch effectively eliminates.
>
> Testing on an 8-socket Westmere-EX server, however, has performance
> change from -9% to than +140% on the fserver workload of AIM7
> depending on how the system was set up.

Subject: [lkp] [locking/mutex] aaca135480: -72.9% fsmark.files_per_sec

My patch also generated the above email.

Please also test that benchmark against this approach.