Re: Hack bench regression with CONFIG_SLUB_CPU_PARTIAL disabled (infoonly)

[Raghavendra K T]

On 07/25/2013 04:35 PM, Eric Dumazet wrote:
> On Thu, 2013-07-25 at 13:30 +0530, Raghavendra K T wrote:
> > Hi,
> >
> > While testing hackbench with 3.11-rc1 I observed hackbench testcase
> > took too long to complete (32 vcpu kvm guest on 32 core HT off machine).
> >
> > hackbench 1x degraded by 3 time (40sec vs 112sec)
> > hackbench 2x degraded by around 20time (90sec vs 1800 sec)
> >
> > When I bisected, I found that I had CONFIG_SLUB_CPU_PARTIAL
> > accidentally disabled.
> > I understand that  CONFIG_SLUB_CPU_PARTIAL=y by default and the config
> > option is to provide determinism for RT kernels and thus it is not a
> > problem.
> > But thought of sharing this here so that if somebody runs into same
> > issue accidently, it would save their time.
>
> Incidentally, what difference do you currently get with SLUB and SLAB ?

tested now,
hackbench 1x is  almost 2 times slower (40 vs 93)
hackbench 2x is almost 6times slower   (90sec vs 528)

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