Re: balance storm

From: Borislav Petkov
Date: Wed May 28 2014 - 06:52:49 EST


On Wed, May 28, 2014 at 12:30:19PM +0200, Peter Zijlstra wrote:
> On Wed, May 28, 2014 at 11:08:40AM +0200, Thomas Gleixner wrote:
> > On Wed, 28 May 2014, Libo Chen wrote:
> >
> > > On 2014/5/28 9:53, Mike Galbraith wrote:
> > > > On Wed, 2014-05-28 at 09:04 +0800, Libo Chen wrote:
> > > >
> > > >> oh yes, no tsc only hpet in my box.
> > > >
> > > > Making poor E5-2658 box a crippled wreck.
> > >
> > > yes,it is. But cpu usage will be down from 15% to 5% when binding
> > > cpu, so maybe read_hpet is not the root cause.
> >
> > Definitely hpet _IS_ the root cause on a machine as large as this,
> > simply because everything gets serialized on the hpet access.
> >
> > Binding stuff to cpus just makes the timing behaviour different, so
> > the hpet serialization is not that prominent, but still bad enough.
> >
> > Talk to your HW/BIOS vendor. The kernel cannot do anything about
> > defunct hardware.
>
> ---
> Subject: x86: FW_BUG when the TSC goes funny on hardware where it really should be stable
>
> It happens far too often on 'consumer' grade hardware, and sometimes on
> 'enterprise' too that the TSC gets marked unstable due to FW fuckage,
> complain more loudly in this case.
>
> Signed-off-by: Peter Zijlstra <peterz@xxxxxxxxxxxxx>

Acked-by: Borislav Petkov <bp@xxxxxxx>

--
Regards/Gruss,
Boris.

Sent from a fat crate under my desk. Formatting is fine.
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