Re: 2.6.25-rc1: volanoMark 45% regression

[Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>]

On Wed, Feb 13, 2008 at 03:15:16PM +0530, Balbir Singh wrote:
> Zhang, Yanmin wrote:
> > volanoMark has 45% regression with kernel 2.6.25-rc1 on my both 8-core
> > stoakley and 16-core Tigerton.
> > 
> > I used bisect to locate below patch.
> > 
> > commit 58e2d4ca581167c2a079f4ee02be2f0bc52e8729
> > Author: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
> > Date:   Fri Jan 25 21:08:00 2008 +0100
> > 
> >     sched: group scheduling, change how cpu load is calculated
> > 
> > 
> > 
> > hackbench has about 30% regression on 16-core tigerton, but has about 10% improvement
> > on 8-core stoakley.
> > 
> > In addition, tbench has about 6% regression on my 8-core stoakley and
> > 25% regression on 16-core stoakley. Some other benchmarks, like netperf/aim7
> > also have some regression. I will verify if they are all related to the
> > patch.
> > 
> > -yanmin
> 
> Hi, Yamin,
> 
> Thanks for reporting the issue? Any chance we could getthe Oprofile output for
> the run? The exact commandline and .config being used would also help.

Yamin,
	I would also like to know against which previous version is this
regression being compared with. Is it 2.6.24? Did you have
CONFIG_FAIR_USER_SCHED enabled in both cases? It would also help to know if you
see the same regression with FAIR_GROUP_SCHED turned off.

-- 
Regards,
vatsa