Re: + filemap-make-the-accounting-of-thrashing-more-consistent.patch added to mm-unstable branch

[CGEL]

On Fri, Aug 12, 2022 at 03:45:09PM +0900, Joonsoo Kim wrote:
> 2022년 8월 12일 (금) 오후 12:48, CGEL <cgel.zte@xxxxxxxxx>님이 작성:
> >
> > We have discussed related question before. See:
> > https://lore.kernel.org/all/Yio17pXawRuuVJFO@xxxxxxxxxxx/
> > The problem is that there is no suitable place to measure pagecache thrashing
> > in fs level likes swap_readpage(). We have to measure it in folio_wait_bit_common().
> >
> > If we measure swap thrashing just in swap_readpage(), we will miss pagecache
> > thrashing. If we measure swap thrashing in swap_readpage(), and measure
> > pagecache thrashing in folio_wait_bit_common(), it will be rerpeated calculation.
> 
> Maybe, repeated calculation issue could be easily solved by
> re-entrance detection on
> delayacct_thrashing_start().
>
If no other suggestion from others, I will commit another patch
to realize this.

And I think this patch will not conflict with the later patch.

Thanks.

> Thanks.