diff options
| author | Johannes Weiner <hannes@cmpxchg.org> | 2009-03-31 15:19:35 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2009-04-01 08:59:12 -0700 |
| commit | 9786bf841da57fac3457a1dac41acb4c1f2eced6 (patch) | |
| tree | 763cb1dd3f6a3c4faf1c31b44ad2e7bef0d206d2 /mm | |
| parent | d979677c4c02f0a72db5a03ecd8184bd9d6695c8 (diff) | |
vmscan: clip swap_cluster_max in shrink_all_memory()
shrink_inactive_list() scans in sc->swap_cluster_max chunks until it hits
the scan limit it was passed.
shrink_inactive_list()
{
do {
isolate_pages(swap_cluster_max)
shrink_page_list()
} while (nr_scanned < max_scan);
}
This assumes that swap_cluster_max is not bigger than the scan limit
because the latter is checked only after at least one iteration.
In shrink_all_memory() sc->swap_cluster_max is initialized to the overall
reclaim goal in the beginning but not decreased while reclaim is making
progress which leads to subsequent calls to shrink_inactive_list()
reclaiming way too much in the one iteration that is done unconditionally.
Set sc->swap_cluster_max always to the proper goal before doing
shrink_all_zones()
shrink_list()
shrink_inactive_list().
While the current shrink_all_memory() happily reclaims more than actually
requested, this patch fixes it to never exceed the goal:
unpatched
wanted=10000 reclaimed=13356
wanted=10000 reclaimed=19711
wanted=10000 reclaimed=10289
wanted=10000 reclaimed=17306
wanted=10000 reclaimed=10700
wanted=10000 reclaimed=10004
wanted=10000 reclaimed=13301
wanted=10000 reclaimed=10976
wanted=10000 reclaimed=10605
wanted=10000 reclaimed=10088
wanted=10000 reclaimed=15000
patched
wanted=10000 reclaimed=10000
wanted=10000 reclaimed=9599
wanted=10000 reclaimed=8476
wanted=10000 reclaimed=8326
wanted=10000 reclaimed=10000
wanted=10000 reclaimed=10000
wanted=10000 reclaimed=9919
wanted=10000 reclaimed=10000
wanted=10000 reclaimed=10000
wanted=10000 reclaimed=10000
wanted=10000 reclaimed=10000
wanted=10000 reclaimed=9624
wanted=10000 reclaimed=10000
wanted=10000 reclaimed=10000
wanted=8500 reclaimed=8092
wanted=316 reclaimed=316
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: MinChan Kim <minchan.kim@gmail.com>
Acked-by: Nigel Cunningham <ncunningham@crca.org.au>
Acked-by: "Rafael J. Wysocki" <rjw@sisk.pl>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/vmscan.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/mm/vmscan.c b/mm/vmscan.c index b15dcbb9e174..9578063cd943 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -2109,7 +2109,6 @@ unsigned long shrink_all_memory(unsigned long nr_pages) struct scan_control sc = { .gfp_mask = GFP_KERNEL, .may_unmap = 0, - .swap_cluster_max = nr_pages, .may_writepage = 1, .isolate_pages = isolate_pages_global, }; @@ -2151,6 +2150,7 @@ unsigned long shrink_all_memory(unsigned long nr_pages) unsigned long nr_to_scan = nr_pages - sc.nr_reclaimed; sc.nr_scanned = 0; + sc.swap_cluster_max = nr_to_scan; shrink_all_zones(nr_to_scan, prio, pass, &sc); if (sc.nr_reclaimed >= nr_pages) goto out; |