Re: [PATCH 0/4] per anon_vma lock and turn anon_vma rwsem lock to rwlock_t

Tim Chen
2013-11-05T02:03:18Z

On Mon, 2013-11-04 at 17:44 -0800, Tim Chen wrote:
> On Mon, 2013-11-04 at 11:59 +0800, Yuanhan Liu wrote:
> > On Fri, Nov 01, 2013 at 08:15:13PM -0700, Davidlohr Bueso wrote:
> > > On Fri, 2013-11-01 at 18:16 +0800, Yuanhan Liu wrote:
> > > > On Fri, Nov 01, 2013 at 09:21:46AM +0100, Ingo Molnar wrote:
> > > > >
> > > > > * Yuanhan Liu <yuanhan.liu@linux.intel.com> wrote:
> > > > >
> > > > > > > Btw., another _really_ interesting comparison would be against
> > > > > > > the latest rwsem patches. Mind doing such a comparison?
> > > > > >
> > > > > > Sure. Where can I get it? Are they on some git tree?
> > > > >
> > > > > I've Cc:-ed Tim Chen who might be able to point you to the latest
> > > > > version.
> > > > >
> > > > > The last on-lkml submission was in this thread:
> > > > >
> > > > > Subject: [PATCH v8 0/9] rwsem performance optimizations
> > > > >
> > > >
> > > > Thanks.
> > > >
> > > > I queued bunchs of tests about one hour ago, and already got some
> > > > results(If necessary, I can add more data tomorrow when those tests are
> > > > finished):
> > >
> > > What kind of system are you using to run these workloads on?
> >
> > I queued jobs on 5 testboxes:
> > - brickland1: 120 core Ivybridge server
> > - lkp-ib03: 48 core Ivybridge server
> > - lkp-sb03: 32 core Sandybridge server
> > - lkp-nex04: 64 core NHM server
> > - lkp-a04: Atom server
> > >
> > > >
> > > >
> > > > v3.12-rc7 fe001e3de090e179f95d
> > > > ------------------------ ------------------------
> > > > -9.3% brickland1/micro/aim7/shared
> > > > +4.3% lkp-ib03/micro/aim7/fork_test
> > > > +2.2% lkp-ib03/micro/aim7/shared
> > > > -2.6% TOTAL aim7.2000.jobs-per-min
> > > >
> > >
> > > Sorry if I'm missing something, but could you elaborate more on what
> > > these percentages represent?
> >
> > v3.12-rc7 fe001e3de090e179f95d
> > ------------------------ ------------------------
> > -9.3% brickland1/micro/aim7/shared
> > ....
> > ....
> > -2.6% TOTAL aim7.2000.jobs-per-min
> >
> > The comparation base is v3.12-rc7, and we got 9.3 performance regression
> > at commit fe001e3de090e179f95d, which is the head of rwsem performance
> > optimizations patch set.
>
> Yunahan, thanks for the data. This I assume is with the entire rwsem
> v8 patchset. Any idea of the run variation on the workload?

Yunhan,

I haven't got a chance to make multiple runs to check the standard
deviation. From the few runs I did, I got a 5.1% increase in
performance for aim7 shared workload for the complete rwsem patchset
on a similar machine that you are using. The patches are applied
to the 3.12-rc7 and compared to the vanilla kernel.

Thanks.

Tim