Re: EEVDF and NUMA balancing

Julia Lawall
2023-10-04T18:04:40Z

> 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.

>
> > The commit e8f331bcc270 starts with
> >
> > - if (sched_feat(PLACE_LAG) && cfs_rq->nr_running > 1) {
> > + if (sched_feat(PLACE_LAG) && cfs_rq->nr_running) {
> >
> > This seemed like a big change - cfs_rq->nr_running > 1 should be rarely
> > true in ua, while cfs_rq->nr_running should always be true. Adding back
> > the > 1 and simply replacing the test by 0 both had no effect, though.
>
> Yeah, this is because I flip the order of place_entity() and
> nr_running++ around later in the patch. Previously it would increment
> before place, now it does place before increment.

Ah, ok, not likely the source of the problem then.

Thanks,
julia