Re: [PATCH v3 04/10] compaction: make isolate_lru_page with filter aware
From: Michal Hocko <hidden>
Date: 2011-06-12 14:50:07
Also in:
lkml
On Tue 07-06-11 23:38:17, Minchan Kim wrote:
In async mode, compaction doesn't migrate dirty or writeback pages. So, it's meaningless to pick the page and re-add it to lru list. Of course, when we isolate the page in compaction, the page might be dirty or writeback but when we try to migrate the page, the page would be not dirty, writeback. So it could be migrated. But it's very unlikely as isolate and migration cycle is much faster than writeout. So, this patch helps cpu and prevent unnecessary LRU churning.
I think you should introduce ISOLATE_CLEAN with this patch. Apart from that it makes perfect sense. Feel free to add my Reviewed-by: Michal Hocko <redacted>
quoted hunk ↗ jump to hunk
Cc: Andrea Arcangeli <redacted> Reviewed-by: KAMEZAWA Hiroyuki <redacted> Reviewed-by: KOSAKI Motohiro <redacted> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Mel Gorman <mgorman@suse.de> Acked-by: Rik van Riel <redacted> Signed-off-by: Minchan Kim <redacted> --- mm/compaction.c | 7 +++++-- 1 files changed, 5 insertions(+), 2 deletions(-)diff --git a/mm/compaction.c b/mm/compaction.c index f0d75e9..8079346 100644 --- a/mm/compaction.c +++ b/mm/compaction.c@@ -243,6 +243,7 @@ static unsigned long isolate_migratepages(struct zone *zone, unsigned long last_pageblock_nr = 0, pageblock_nr; unsigned long nr_scanned = 0, nr_isolated = 0; struct list_head *migratelist = &cc->migratepages; + enum ISOLATE_MODE mode = ISOLATE_ACTIVE|ISOLATE_INACTIVE; /* Do not scan outside zone boundaries */ low_pfn = max(cc->migrate_pfn, zone->zone_start_pfn);@@ -326,9 +327,11 @@ static unsigned long isolate_migratepages(struct zone *zone, continue; } + if (!cc->sync) + mode |= ISOLATE_CLEAN; + /* Try isolate the page */ - if (__isolate_lru_page(page, - ISOLATE_ACTIVE|ISOLATE_INACTIVE, 0) != 0) + if (__isolate_lru_page(page, mode, 0) != 0) continue; VM_BUG_ON(PageTransCompound(page));-- 1.7.0.4 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. 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=mailto:"dont@kvack.org"> email@kvack.org </a>
-- Michal Hocko SUSE Labs SUSE LINUX s.r.o. Lihovarska 1060/12 190 00 Praha 9 Czech Republic -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. 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=mailto:"dont@kvack.org"> email@kvack.org </a>