Re: Receive side performance issue with multi-10-GigE and NUMA

[Jesse Barnes <jbarnes@virtuousgeek.org>]

On Wed, 12 Aug 2009 00:38:24 -0400
Bill Fink <billfink@mindspring.com> wrote:

> On Tue, 11 Aug 2009, Brandeburg, Jesse wrote:
> 
> > Bill Fink wrote:
> > > On Sat, 8 Aug 2009, Neil Horman wrote:
> > > 
> > >> On Sat, Aug 08, 2009 at 02:21:36PM -0400, Andrew Gallatin wrote:
> > >>> Neil Horman wrote:
> > >>>> On Sat, Aug 08, 2009 at 07:08:20AM -0400, Andrew Gallatin
> > >>>> wrote:
> > >>>>> Bill Fink wrote:
> > >>>>>> On Fri, 07 Aug 2009, Andrew Gallatin wrote:
> > >>>>>> 
> > >>>>>>> Bill Fink wrote:
> > >>>>>>> 
> > >>>>>>>> All sysfs local_cpus values are the same
> > >>>>>>>> (00000000,000000ff), so yes they are also wrong.
> > 
> > bill, I recently helped Jesse Barnes push a patch that addresses
> > this kind of issue on CoreI7, the root cause was the numa_node
> > variable was initialized based on slot on AMD systems, but needed
> > to be set to -1 by default on systems with a uniform IOH to slot
> > architecture.
> > 
> > here is the commit ID:
> > http://git.kernel.org/?p=linux/kernel/git/sfr/linux-next.git;a=commit;h=3c38
> > d674be519109696746192943a6d524019f7f
> > 
> > I'm not sure it is in linus' tree yet, this link is to net-next
> > 
> > Maybe see if it helps?
> 
> It's worth a shot.
> 
> Hopefully I can get a chance to build a new kernel tomorrow to check
> out some of the suggestions, like this one, the setting of ACPI_DEBUG,
> and the new ftrace module for checking NUMA affinity of skbs.

It's a fairly significant change so I wasn't planning on sending it to
Linus for 2.6.31.  If you think it *should* go into 2.6.31 (and stable
for that matter), please let me know soon.

Thanks,
-- 
Jesse Barnes, Intel Open Source Technology Center