On Mon, Sep 06, 2010 at 06:47:31PM +0800, Mel Gorman wrote: > From: KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx> > > isolate_lru_pages() does not just isolate LRU tail pages, but also isolate > neighbour pages of the eviction page. The neighbour search does not stop even > if neighbours cannot be isolated which is excessive as the lumpy reclaim will > no longer result in a successful higher order allocation. This patch stops > the PFN neighbour pages if an isolation fails and moves on to the next block. > > Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx> > Signed-off-by: Mel Gorman <mel@xxxxxxxxx> > --- > mm/vmscan.c | 24 ++++++++++++++++-------- > 1 files changed, 16 insertions(+), 8 deletions(-) > > diff --git a/mm/vmscan.c b/mm/vmscan.c > index 64f9ca5..ff52b46 100644 > --- a/mm/vmscan.c > +++ b/mm/vmscan.c > @@ -1047,14 +1047,18 @@ static unsigned long isolate_lru_pages(unsigned long nr_to_scan, > continue; > > /* Avoid holes within the zone. */ > - if (unlikely(!pfn_valid_within(pfn))) > + if (unlikely(!pfn_valid_within(pfn))) { > + nr_lumpy_failed++; > break; > + } > > cursor_page = pfn_to_page(pfn); > > /* Check that we have not crossed a zone boundary. */ > - if (unlikely(page_zone_id(cursor_page) != zone_id)) > - continue; > + if (unlikely(page_zone_id(cursor_page) != zone_id)) { > + nr_lumpy_failed++; > + break; > + } > > /* > * If we don't have enough swap space, reclaiming of > @@ -1062,8 +1066,10 @@ static unsigned long isolate_lru_pages(unsigned long nr_to_scan, > * pointless. > */ > if (nr_swap_pages <= 0 && PageAnon(cursor_page) && > - !PageSwapCache(cursor_page)) > - continue; > + !PageSwapCache(cursor_page)) { > + nr_lumpy_failed++; > + break; > + } > > if (__isolate_lru_page(cursor_page, mode, file) == 0) { > list_move(&cursor_page->lru, dst); > @@ -1074,9 +1080,11 @@ static unsigned long isolate_lru_pages(unsigned long nr_to_scan, > nr_lumpy_dirty++; > scan++; > } else { > - if (mode == ISOLATE_BOTH && > - page_count(cursor_page)) > - nr_lumpy_failed++; > + /* the page is freed already. */ > + if (!page_count(cursor_page)) > + continue; > + nr_lumpy_failed++; > + break; > } > } The many nr_lumpy_failed++ can be moved here: if (pfn < end_pfn) nr_lumpy_failed++; Reviewed-by: Wu Fengguang <fengguang.wu@xxxxxxxxx> -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html