[PATCH] zoned vm counters: zone_reclaim: remove /proc/sys/vm/zone_reclaim_interval

The zone_reclaim_interval was necessary because we were not able to determine
how many unmapped pages exist in a zone.  Therefore we had to scan in
intervals to figure out if any pages were unmapped.

With the zoned counters and NR_ANON_PAGES we now know the number of pagecache
pages and the number of mapped pages in a zone.  So we can simply skip the
reclaim if there is an insufficient number of unmapped pages.  We use
SWAP_CLUSTER_MAX as the boundary.

Drop all support for /proc/sys/vm/zone_reclaim_interval.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

2 files changed, 0 insertions, 7 deletions

diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index 4833abd4458b..839e9a04fd49 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -178,12 +178,6 @@ struct zone {
 
         /* Zone statistics */
         atomic_long_t           vm_stat[NR_VM_ZONE_STAT_ITEMS];
-        /*
-         * timestamp (in jiffies) of the last zone reclaim that did not
-         * result in freeing of pages. This is used to avoid repeated scans
-         * if all memory in the zone is in use.
-         */
-        unsigned long           last_unsuccessful_zone_reclaim;
 
         /*
          * prev_priority holds the scanning priority for this zone.  It is
diff --git a/include/linux/swap.h b/include/linux/swap.h
index c41e2d6d1acc..cf6ca6e377bd 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -189,7 +189,6 @@ extern long vm_total_pages;
 
 #ifdef CONFIG_NUMA
 extern int zone_reclaim_mode;
-extern int zone_reclaim_interval;
 extern int zone_reclaim(struct zone *, gfp_t, unsigned int);
 #else
 #define zone_reclaim_mode 0