Re: [PATCH 00/33] AutoNUMA27

[Andrea Arcangeli <aarcange@redhat.com>]

Hi Srikar,

On Sun, Oct 14, 2012 at 12:10:19AM +0530, Srikar Dronamraju wrote:
> * Andrea Arcangeli <aarcange@redhat.com> [2012-10-04 01:50:42]:
> 
> > Hello everyone,
> > 
> > This is a new AutoNUMA27 release for Linux v3.6.
> > 
> 
> 
> Here results of autonumabenchmark on a 328GB 64 core with ht disabled
> comparing v3.6 with autonuma27.

*snip*

>                           numa01: 1805.19  1907.11  1866.39    -3.88%  

Interesting. So numa01 should be improved in autonuma28fast. Not sure
why the hard binds show any difference, but I'm more concerned in
optimizing numa01. I get the same results from hard bindings on
upstream or autonuma, strange.

Could you repeat only numa01 with the origin/autonuma28fast branch?
Also if you could post the two pdf convergence chart generated by
numa01 on autonuma27 and autonuma28fast, I think that would be
interesting to see the full effect and why it is faster.

I only had the time for a quick push after having the idea added in
autonuma28fast (which is yet improved compared to autonuma28), but
I've been told already that it's dealing with numa01 on the 8 node
very well as expected.

numa01 in the 8 node is a workload without a perfect solution (other
than MADV_INTERLEAVE). Full convergence preventing cross-node traffic
is impossible because there are 2 processes spanning over 8 nodes and
all process memory is touched by all threads constantly. Yet
autonuma28fast should deal optimally that scenario too.

As a side note: numa01 on the 2 node instead converges fully (2
processes + 2 nodes = full convergence). numa01 on 2 nodes or >2nodes
is a very different kind of test.

I'll release an autonuma29 behaving like 28fast if there are no
surprises. The new algorithm change in 28fast will also save memory
once I rewrite it properly.

Thanks!
Andrea