[PATCH] vm: add per-zone writeout counter
The VM is supposed to minimise the number of pages which get written off the
LRU (for IO scheduling efficiency, and for high reclaim-success rates). But
we don't actually have a clear way of showing how true this is.
So add `nr_vmscan_write' to /proc/vmstat and /proc/zoneinfo - the number of
pages which have been written by the vm scanner in this zone and globally.
Cc: Christoph Lameter <clameter@engr.sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/mm/vmstat.c b/mm/vmstat.c
index 490d8c1..69c6571 100644
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -465,6 +465,7 @@
"nr_writeback",
"nr_unstable",
"nr_bounce",
+ "nr_vmscan_write",
#ifdef CONFIG_NUMA
"numa_hit",