memcg: fix calculation of active_ratio
Currently, inactive_ratio of memcg is calculated at setting limit.
because page_alloc.c does so and current implementation is straightforward
porting.
However, memcg introduced hierarchy feature recently. In hierarchy
restriction, memory limit is not only decided memory.limit_in_bytes of
current cgroup, but also parent limit and sibling memory usage.
Then, The optimal inactive_ratio is changed frequently. So, everytime
calculation is better.
Tested-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index ab2ecbb..c7d78ec 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -166,9 +166,6 @@
unsigned int swappiness;
-
- unsigned int inactive_ratio;
-
/*
* statistics. This must be placed at the end of memcg.
*/
@@ -432,15 +429,43 @@
spin_unlock(&mem->reclaim_param_lock);
}
-int mem_cgroup_inactive_anon_is_low(struct mem_cgroup *memcg, struct zone *zone)
+static int calc_inactive_ratio(struct mem_cgroup *memcg, unsigned long *present_pages)
{
unsigned long active;
unsigned long inactive;
+ unsigned long gb;
+ unsigned long inactive_ratio;
inactive = mem_cgroup_get_all_zonestat(memcg, LRU_INACTIVE_ANON);
active = mem_cgroup_get_all_zonestat(memcg, LRU_ACTIVE_ANON);
- if (inactive * memcg->inactive_ratio < active)
+ gb = (inactive + active) >> (30 - PAGE_SHIFT);
+ if (gb)
+ inactive_ratio = int_sqrt(10 * gb);
+ else
+ inactive_ratio = 1;
+
+ if (present_pages) {
+ present_pages[0] = inactive;
+ present_pages[1] = active;
+ }
+
+ return inactive_ratio;
+}
+
+int mem_cgroup_inactive_anon_is_low(struct mem_cgroup *memcg)
+{
+ unsigned long active;
+ unsigned long inactive;
+ unsigned long present_pages[2];
+ unsigned long inactive_ratio;
+
+ inactive_ratio = calc_inactive_ratio(memcg, present_pages);
+
+ inactive = present_pages[0];
+ active = present_pages[1];
+
+ if (inactive * inactive_ratio < active)
return 1;
return 0;
@@ -1432,29 +1457,6 @@
return 0;
}
-/*
- * The inactive anon list should be small enough that the VM never has to
- * do too much work, but large enough that each inactive page has a chance
- * to be referenced again before it is swapped out.
- *
- * this calculation is straightforward porting from
- * page_alloc.c::setup_per_zone_inactive_ratio().
- * it describe more detail.
- */
-static void mem_cgroup_set_inactive_ratio(struct mem_cgroup *memcg)
-{
- unsigned int gb, ratio;
-
- gb = res_counter_read_u64(&memcg->res, RES_LIMIT) >> 30;
- if (gb)
- ratio = int_sqrt(10 * gb);
- else
- ratio = 1;
-
- memcg->inactive_ratio = ratio;
-
-}
-
static DEFINE_MUTEX(set_limit_mutex);
static int mem_cgroup_resize_limit(struct mem_cgroup *memcg,
@@ -1496,9 +1498,6 @@
if (!progress) retry_count--;
}
- if (!ret)
- mem_cgroup_set_inactive_ratio(memcg);
-
return ret;
}
@@ -1858,7 +1857,7 @@
}
#ifdef CONFIG_DEBUG_VM
- cb->fill(cb, "inactive_ratio", mem_cont->inactive_ratio);
+ cb->fill(cb, "inactive_ratio", calc_inactive_ratio(mem_cont, NULL));
{
int nid, zid;
@@ -2150,7 +2149,6 @@
res_counter_init(&mem->res, NULL);
res_counter_init(&mem->memsw, NULL);
}
- mem_cgroup_set_inactive_ratio(mem);
mem->last_scanned_child = NULL;
spin_lock_init(&mem->reclaim_param_lock);