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

From: Waiman Long
Date: Tue Feb 16 2016 - 20:54:43 EST


On 02/16/2016 03:51 AM, Peter Zijlstra wrote:
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.


I will ran that benchmark on my patch.

Cheers,
Longman