Re: [RFC PATCH 00/19] Cleanup and optimise the page allocator V2

Pekka Enberg
2009-02-26T11:19:21Z

On Thu, 2009-02-26 at 11:03 +0000, Mel Gorman wrote:
> On Thu, Feb 26, 2009 at 05:10:27PM +0800, Lin Ming wrote:
> > We tested this v2 patch series with 2.6.29-rc6 on different machines.
> >
>
> Wonderful, thanks.
>
> > 4P qual-core 2P qual-core 2P qual-core HT
> > tigerton stockley Nehalem
> > ------------------------------------------------
> > tbench +3% +2% 0%
>
> Nice.
>
> > oltp -2% 0% 0%
>
> This is a big disappointment and somewhat confusing that it is so
> severe. For sysbench I was seeing on six different machines;
>
> 50834.14 51763.08 1.79%
> 61852.08 61966.58 0.18%
> 5935.98 5980.06 0.74%
> 29227.78 30167.72 3.12%
> 66702.67 66534.76 -0.25%
> 26643.18 26542.59 -0.38%
>
> So, two smallish regressions but mainly gains. Then again, I'm becoming
> more and more convinced that sysbench doesn't really represent a proper
> OLTP workload.
>
> I'd like to understand more how the page allocator at least was being used
> during your tests. Would it be possible to get a full profile (including
> instruction if possible and the vmlinux file) for both kernels please?
>
> If you can get the profiles, confirm the regression is still there as
> sometimes profiling can alter the outcome. Even if this happens, the
> profile will tell me where time is being spent.
>
> > aim7 0% 0% 0%
> > specjbb2005 +3% 0% 0%
> > hackbench 0% 0% 0%
> >
> > netperf:
> > TCP-S-112k 0% -1% 0%
> > TCP-S-64k 0% -1% +1%
> > TCP-RR-1 0% 0% +1%
> > UDP-U-4k -2% 0% -2%
>
> Pekka, for this test was SLUB or the page allocator handling the 4K
> allocations?

The page allocator. The pass-through revert is not in 2.6.29-rc6 and I
won't be sending it until 2.6.30 opens up.

>
> > UDP-U-1k +3% 0% 0%
> > UDP-RR-1 0% 0% 0%
> > UDP-RR-512 -1% 0% +1%
> >
> > Lin Ming
> >
>
> Thanks a million for testing.
>