Re: [LKP] [sched/numa] a43455a1d57: +94.1% proc-vmstat.numa_hint_faults_local

[Jirka Hladky]

On 07/31/2014 05:57 PM, Peter Zijlstra wrote:
> On Thu, Jul 31, 2014 at 12:42:41PM +0200, Peter Zijlstra wrote:
> > On Tue, Jul 29, 2014 at 02:39:40AM -0400, Rik van Riel wrote:
> > > On Tue, 29 Jul 2014 13:24:05 +0800
> > > Aaron Lu <aaron.lu@xxxxxxxxx> wrote:
> > >
> > > > FYI, we noticed the below changes on
> > > >
> > > > git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master
> > > > commit a43455a1d572daf7b730fe12eb747d1e17411365 ("sched/numa: Ensure task_numa_migrate() checks the preferred node")
> > > >
> > > > ebe06187bf2aec1  a43455a1d572daf7b730fe12e
> > > > ---------------  -------------------------
> > > >       94500 ~ 3%    +115.6%     203711 ~ 6%  ivb42/hackbench/50%-threads-pipe
> > > >       67745 ~ 4%     +64.1%     111174 ~ 5%  lkp-snb01/hackbench/50%-threads-socket
> > > >      162245 ~ 3%     +94.1%     314885 ~ 6%  TOTAL proc-vmstat.numa_hint_faults_local
> > > Hi Aaron,
> > >
> > > Jirka Hladky has reported a regression with that changeset as
> > > well, and I have already spent some time debugging the issue.
> > Let me see if I can still find my SPECjbb2005 copy to see what that
> > does.
> Jirka, what kind of setup were you seeing SPECjbb regressions?
>
> I'm not seeing any on 2 sockets with a single SPECjbb instance, I'll go
> check one instance per socket now.
Peter, I'm seeing regressions for

SINGLE SPECjbb instance for number of warehouses being the same as total 
number of cores in the box.

Example: 4 NUMA node box, each CPU has 6 cores => biggest regression is 
for 24 warehouses.

See the attached snapshot.

Jirka

Attachment: SPECjbb2005_-127.el7numafixes9.png
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