Messages in this thread | | | Date | Tue, 3 May 2011 09:29:59 +0900 | Subject | Re: [PATCH 2/2] Filter unevictable page out in deactivate_page | From | Minchan Kim <> |
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Hi KOSAKI,
On Mon, May 2, 2011 at 7:37 PM, KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> wrote: >> It's pointless that deactive_page's pagevec operation about >> unevictable page as it's nop. >> This patch removes unnecessary overhead which might be a bit problem >> in case that there are many unevictable page in system(ex, mprotect workload) >> >> Signed-off-by: Minchan Kim <minchan.kim@gmail.com> >> --- >> mm/swap.c | 9 +++++++++ >> 1 files changed, 9 insertions(+), 0 deletions(-) >> >> diff --git a/mm/swap.c b/mm/swap.c >> index 2e9656d..b707694 100644 >> --- a/mm/swap.c >> +++ b/mm/swap.c >> @@ -511,6 +511,15 @@ static void drain_cpu_pagevecs(int cpu) >> */ >> void deactivate_page(struct page *page) >> { >> + >> + /* >> + * In workload which system has many unevictable page(ex, mprotect), >> + * unevictalge page deactivation for accelerating reclaim >> + * is pointless. >> + */ >> + if (PageUnevictable(page)) >> + return; >> + > > Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> >
Thanks!
> > btw, I think we should check PageLRU too. >
Yes. I remember you advised it when we push this patch but I didn't. That's because I think most of pages in such context would be LRU as they are cached pages. So IMO, PageLRU checking in deactivate_page couldn't help much.
-- Kind regards, Minchan Kim -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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