Hi Rik On Fri, Jan 27, 2012 at 3:59 AM, Rik van Riel <riel@xxxxxxxxxx> wrote: > When built with CONFIG_COMPACTION, kswapd should not try to free > contiguous pages, because it is not trying hard enough to have > a real chance at being successful, but still disrupts the LRU > enough to break other things. > > Do not do higher order page isolation unless we really are in > lumpy reclaim mode. > > Stop reclaiming pages once we have enough free pages that > compaction can deal with things, and we hit the normal order 0 > watermarks used by kswapd. > > Also remove a line of code that increments balanced right before > exiting the function. > > Signed-off-by: Rik van Riel <riel@xxxxxxxxxx> > --- > -v4: further cleanups suggested by Mel Gorman > mm/vmscan.c | 43 +++++++++++++++++++++++++++++-------------- > 1 files changed, 29 insertions(+), 14 deletions(-) > > diff --git a/mm/vmscan.c b/mm/vmscan.c > index 2880396..2e2e43d 100644 > --- a/mm/vmscan.c > +++ b/mm/vmscan.c > @@ -1139,7 +1139,7 @@ int __isolate_lru_page(struct page *page, isolate_mode_t mode, int file) > * @mz: The mem_cgroup_zone to pull pages from. > * @dst: The temp list to put pages on to. > * @nr_scanned: The number of pages that were scanned. > - * @order: The caller's attempted allocation order > + * @sc: The scan_control struct for this reclaim session > * @mode: One of the LRU isolation modes > * @active: True [1] if isolating active pages > * @file: True [1] if isolating file [!anon] pages > @@ -1148,8 +1148,8 @@ int __isolate_lru_page(struct page *page, isolate_mode_t mode, int file) > */ > static unsigned long isolate_lru_pages(unsigned long nr_to_scan, > struct mem_cgroup_zone *mz, struct list_head *dst, > - unsigned long *nr_scanned, int order, isolate_mode_t mode, > - int active, int file) > + unsigned long *nr_scanned, struct scan_control *sc, > + isolate_mode_t mode, int active, int file) > { > struct lruvec *lruvec; > struct list_head *src; > @@ -1195,7 +1195,7 @@ static unsigned long isolate_lru_pages(unsigned long nr_to_scan, > BUG(); > } > > - if (!order) > + if (!sc->order || !(sc->reclaim_mode & RECLAIM_MODE_LUMPYRECLAIM)) > continue; > Just a tiny advice 8-) mind to move checking lumpy reclaim out of the loop, something like unsigned long nr_lumpy_failed = 0; unsigned long scan; int lru = LRU_BASE; + int order = sc->order; + + if (!(sc->reclaim_mode & RECLAIM_MODE_LUMPYRECLAIM)) + order = 0; lruvec = mem_cgroup_zone_lruvec(mz->zone, mz->mem_cgroup); if (active) lru += LRU_ACTIVE; with a line of comment? Hillf -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href