Messages in this thread | | | Date | Tue, 9 Aug 2011 08:51:30 +0900 | From | KAMEZAWA Hiroyuki <> | Subject | Re: [PATCH 1/2] vmscan: promote shared file mapped pages |
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On Mon, 8 Aug 2011 15:06:58 +0400 Konstantin Khlebnikov <khlebnikov@openvz.org> wrote:
> Commit v2.6.33-5448-g6457474 (vmscan: detect mapped file pages used only once) > greatly decreases lifetime of single-used mapped file pages. > Unfortunately it also decreases life time of all shared mapped file pages. > Because after commit v2.6.28-6130-gbf3f3bc (mm: don't mark_page_accessed in fault path) > page-fault handler does not mark page active or even referenced. > > Thus page_check_references() activates file page only if it was used twice while > it stays in inactive list, meanwhile it activates anon pages after first access. > Inactive list can be small enough, this way reclaimer can accidentally > throw away any widely used page if it wasn't used twice in short period. > > After this patch page_check_references() also activate file mapped page at first > inactive list scan if this page is already used multiple times via several ptes. > > Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
As other guys pointed out, it's better to show performance score change by this patch in changelog.
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
> --- > mm/vmscan.c | 2 +- > 1 files changed, 1 insertions(+), 1 deletions(-) > > diff --git a/mm/vmscan.c b/mm/vmscan.c > index 47403c9..3cd766d 100644 > --- a/mm/vmscan.c > +++ b/mm/vmscan.c > @@ -724,7 +724,7 @@ static enum page_references page_check_references(struct page *page, > */ > SetPageReferenced(page); > > - if (referenced_page) > + if (referenced_page || referenced_ptes > 1) > return PAGEREF_ACTIVATE; > > return PAGEREF_KEEP; > >
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