Make vm statistics update interval configurable

Make it configurable.  Code in mm makes the vm statistics intervals
independent from the cache reaper use that opportunity to make it
configurable.

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

1 files changed, 3 insertions, 1 deletions

diff --git a/mm/vmstat.c b/mm/vmstat.c
index 9d824643a22f..006eb7621869 100644
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -641,11 +641,13 @@ const struct seq_operations vmstat_op = {
 
 #ifdef CONFIG_SMP
 static DEFINE_PER_CPU(struct delayed_work, vmstat_work);
+int sysctl_stat_interval __read_mostly = HZ;
 
 static void vmstat_update(struct work_struct *w)
 {
         refresh_cpu_vm_stats(smp_processor_id());
-        schedule_delayed_work(&__get_cpu_var(vmstat_work), HZ);
+        schedule_delayed_work(&__get_cpu_var(vmstat_work),
+                sysctl_stat_interval);
 }
 
 static void __devinit start_cpu_timer(int cpu)