Re: EEVDF and NUMA balancing

Julia Lawall
2023-10-09T14:07:39Z

On Mon, 9 Oct 2023, Peter Zijlstra wrote:

> On Wed, Oct 04, 2023 at 08:04:34PM +0200, Julia Lawall wrote:
> > > I'll go build the benchmark thing tomorrow, if I can figure out how that
> > > works, this NAS stuff looked 'special'. Nothing simple like ./configure;
> > > make -j$lots :/
> >
> > Starting from git clone, I had to do:
> >
> > cd NPB3.4-OMP
> > mkdir bin
> > cd config
> > cp make.def.template make.def
> > cd ..
> > make ua CLASS=C
> >
> > You also need gfortran to be installed.
>
> W00t, that worked like a charm.
>
> The sad new is that I can't seem to reproduce the issue:
>
> So my (freshly re-installed with debian testing) 4 socket Intel(R)
> Xeon(R) CPU E7-8890 v3 machine gives me:
>
> root@hsw-ex:/usr/local/src/nas-parallel-benchmarks/NPB3.4-OMP/bin# uname -a
> Linux hsw-ex 6.6.0-rc4+ #2 SMP PREEMPT_DYNAMIC Mon Oct 9 11:14:21 CEST 2023 x86_64 GNU/Linux
> root@hsw-ex:/usr/local/src/nas-parallel-benchmarks/NPB3.4-OMP/bin# cat /proc/sys/kernel/numa_balancing
> 1
> root@hsw-ex:/usr/local/src/nas-parallel-benchmarks/NPB3.4-OMP/bin# ./ua.C.x | grep "Time in seconds"
> Time in seconds = 26.69
> root@hsw-ex:/usr/local/src/nas-parallel-benchmarks/NPB3.4-OMP/bin# ./ua.C.x | grep "Time in seconds"
> Time in seconds = 26.31
> root@hsw-ex:/usr/local/src/nas-parallel-benchmarks/NPB3.4-OMP/bin# ./ua.C.x | grep "Time in seconds"
> Time in seconds = 25.43

How many runs did you try? I would suggest 50.

25-26 looks like what I get when things go well.

julia

>
>
> And this is using a .config very near what Debian ships for 6.5 (make
> olddefconfig -CONFIG_DEBUG_INFO_BTF)
>
> I'll try again in a little bit, perhaps I'm suffering PEBKAC :-)
>
>
>