Re: [PATCH 5/8] mm: compaction: avoid overwork in migrate sync mode

From: Rik van Riel
Date: Mon Nov 21 2011 - 17:00:00 EST


On 11/19/2011 02:54 PM, Andrea Arcangeli wrote:
Add a lightweight sync migration (sync == 2) mode that avoids overwork
so more suitable to be used by compaction to provide lower latency but

--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -552,7 +552,7 @@ static int compact_zone(struct zone *zone, struct compact_control *cc)
nr_migrate = cc->nr_migratepages;
err = migrate_pages(&cc->migratepages, compaction_alloc,
(unsigned long)cc, false,
- cc->sync);
+ cc->sync ? 2 : 0);

Great idea, but it would be good if these numbers got
a symbolic name so people trying to learn the code can
figure it out a little easier.

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/