On Mon, Dec 27, 2021 at 11:19:32AM +0800, Huang, Ying wrote:
> cgel.zte@xxxxxxxxx writes:
>
> > From: Yang Yang <yang.yang29@xxxxxxxxxx>
> >
> > There are interfaces to adjust max_ptes_none, max_ptes_swap,
> > max_ptes_shared values, see
> > /sys/kernel/mm/transparent_hugepage/khugepaged/.
> >
> > But system administrator maynot know which value is the best. So
> > Add those events to support adjusting max_ptes_* to suitable values.
> >
> > For example, if default max_ptes_swap value causes too much failures,
> > and system uses zram whose IO is fast, administrator could increase
> > max_ptes_swap until THP_SCAN_EXCEED_SWAP_PTE not increase anymore.
> >
> > Signed-off-by: Yang Yang <yang.yang29@xxxxxxxxxx>
> > ---
> > include/linux/vm_event_item.h | 3 +++
> > mm/khugepaged.c | 7 +++++++
> > mm/vmstat.c | 3 +++
> > 3 files changed, 13 insertions(+)
> >
> > diff --git a/include/linux/vm_event_item.h b/include/linux/vm_event_item.h
> > index a185cc75ff52..7b2363388bfa 100644
> > --- a/include/linux/vm_event_item.h
> > +++ b/include/linux/vm_event_item.h
> > @@ -98,6 +98,9 @@ enum vm_event_item { PGPGIN, PGPGOUT, PSWPIN, PSWPOUT,
> > THP_SPLIT_PAGE_FAILED,
> > THP_DEFERRED_SPLIT_PAGE,
> > THP_SPLIT_PMD,
> > + THP_SCAN_EXCEED_NONE_PTE,
> > + THP_SCAN_EXCEED_SWAP_PTE,
> > + THP_SCAN_EXCEED_SHARED_PTE,
>
> "SCAN" appears too general, how about
>
> THP_COLLAPSE_EXCEED_SWAP_PTE
>
> ?
>
Thanks for your suggesting.
But I think SCAN is easy to understand, it is SCAN behaviour cause the event,
and we know this event is comes from SCAN_EXCEED_*_PTE.
> Best Regards,
> Huang, Ying
>
> [snip]
