Re: [RFC PATCH 0/6] mm: thp: use generic THP migration for NUMA hinting fault

[Yang Shi]

On Wed, Mar 31, 2021 at 6:20 AM Mel Gorman <mgorman@xxxxxxx> wrote:
>
> On Tue, Mar 30, 2021 at 04:42:00PM +0200, Gerald Schaefer wrote:
> > Could there be a work-around by splitting THP pages instead of marking them
> > as migrate pmds (via pte swap entries), at least when THP migration is not
> > supported? I guess it could also be acceptable if THP pages were simply not
> > migrated for NUMA balancing on s390, but then we might need some extra config
> > option to make that behavior explicit.
> >
>
> The split is not done on other architectures simply because the loss
> from splitting exceeded the gain of improved locality in too many cases.
> However, it might be ok as an s390-specific workaround.
>
> (Note, I haven't read the rest of the series due to lack of time but this
> query caught my eye).

Will wait for your comments before I post v2. Thanks.

>
> --
> Mel Gorman
> SUSE Labs