Messages in this thread | | | Subject | Re: Performance regression from switching lock to rw-sem for anon-vma tree | From | Davidlohr Bueso <> | Date | Mon, 17 Jun 2013 16:35:20 -0700 |
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On Tue, 2013-06-18 at 07:20 +0800, Alex Shi wrote: > On 06/18/2013 12:22 AM, Davidlohr Bueso wrote: > > After a lot of benchmarking, I finally got the ideal results for aim7, > > so far: this patch + optimistic spinning with preemption disabled. Just > > like optimistic spinning, this patch by itself makes little to no > > difference, yet combined is where we actually outperform 3.10-rc5. In > > addition, I noticed extra throughput when disabling preemption in > > try_optimistic_spin(). > > > > With i_mmap as a rwsem and these changes I could see performance > > benefits for alltests (+14.5%), custom (+17%), disk (+11%), high_systime > > (+5%), shared (+15%) and short (+4%), most of them after around 500 > > users, for fewer users, it made little to no difference. > > A pretty good number. what's the cpu number in your machine? :)
8-socket, 80 cores (ht off)
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