Re: [PATCH 4/4] mm: make every pte dirty on do_swap_page

Rik van Riel
2015-04-10T00:14:57Z

On 04/09/2015 04:59 PM, Andrew Morton wrote:
> On Thu, 9 Apr 2015 08:50:25 +0900 Minchan Kim <minchan@kernel.org> wrote:
>
>> Bump.
>
> I'm getting the feeling that MADV_FREE is out of control.
>
> Below is the overall rollup of
>
> mm-support-madvisemadv_free.patch
> mm-support-madvisemadv_free-fix.patch
> mm-support-madvisemadv_free-fix-2.patch
> mm-dont-split-thp-page-when-syscall-is-called.patch
> mm-dont-split-thp-page-when-syscall-is-called-fix.patch
> mm-dont-split-thp-page-when-syscall-is-called-fix-2.patch
> mm-free-swp_entry-in-madvise_free.patch
> mm-move-lazy-free-pages-to-inactive-list.patch
> mm-move-lazy-free-pages-to-inactive-list-fix.patch
> mm-move-lazy-free-pages-to-inactive-list-fix-fix.patch
> mm-move-lazy-free-pages-to-inactive-list-fix-fix-fix.patch
> mm-make-every-pte-dirty-on-do_swap_page.patch
>
>
> It's pretty large and has its sticky little paws in all sorts of places.
>
>
> The feature would need to be pretty darn useful to justify a mainline
> merge. Has any such usefulness been demonstrated?

The performance increase of MADV_FREE over MADV_DONTNEED is
quite significant. I suspect this is especially important for
mobile devices, which are more memory starved than desktop
systems and servers.

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