Messages in this thread Patch in this message | | | From | KOSAKI Motohiro <> | Subject | Re: [PATCH] Prevent shrinking of active anon lru list in case of no swap space | Date | Thu, 14 May 2009 16:19:52 +0900 (JST) |
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> > Now shrink_active_list is called several places. > But if we don't have a swap space, we can't reclaim anon pages. > So, we don't need deactivating anon pages in anon lru list. > > Signed-off-by: Minchan Kim <minchan.kim@gmail.com> > Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> > Cc: Johannes Weiner <hannes@cmpxchg.org> > Cc: Rik van Riel <riel@redhat.com>
hm, The analysis seems right. but
In general branch should put into non frequency path. why caller modification as following patch is wrong?
/* * Do some background aging of the anon list, to give * pages a chance to be referenced before reclaiming. */ - if (inactive_anon_is_low(zone, &sc)) + if (inactive_anon_is_low(zone, &sc) && (nr_swap_pages <= 0)) shrink_active_list(SWAP_CLUSTER_MAX, zone, &sc, priority, 0);
> --- > mm/vmscan.c | 6 ++++++ > 1 files changed, 6 insertions(+), 0 deletions(-) > > diff --git a/mm/vmscan.c b/mm/vmscan.c > index 2f9d555..e4d71f4 100644 > --- a/mm/vmscan.c > +++ b/mm/vmscan.c > @@ -1238,6 +1238,12 @@ static void shrink_active_list(unsigned long nr_pages, struct zone *zone, > enum lru_list lru; > struct zone_reclaim_stat *reclaim_stat = get_reclaim_stat(zone, sc); > > + /* > + * we can't shrink anon list in case of no swap space. > + */ > + if (file == 0 && nr_swap_pages <= 0) > + return; > + > > lru_add_drain(); > spin_lock_irq(&zone->lru_lock); > pgmoved = sc->isolate_pages(nr_pages, &l_hold, &pgscanned, sc->order, > -- > 1.5.4.3 > > > -- > Kinds Regards > Minchan Kim
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