mem_cgroup_force_empty() tries to free only 32 (SWAP_CLUSTER_MAX) pages on each iteration, if a memory cgroup has lots of page cache, it will take many iterations to empty all page cache, so increase the reclaimed number per iteration to speed it up. same as in mem_cgroup_resize_limit() a simple test show: $dd if=aaa of=bbb bs=1k count=3886080 $rm -f bbb $time echo 100000000 >/cgroup/memory/test/memory.limit_in_bytes Before: 0m0.252s ===> after: 0m0.178s Signed-off-by: Li RongQing <lirongqing@xxxxxxxxx> --- mm/memcontrol.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 670e99b68aa6..8910d9e8e908 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -2480,7 +2480,7 @@ static int mem_cgroup_resize_limit(struct mem_cgroup *memcg, if (!ret) break; - if (!try_to_free_mem_cgroup_pages(memcg, 1, + if (!try_to_free_mem_cgroup_pages(memcg, 1024, GFP_KERNEL, !memsw)) { ret = -EBUSY; break; @@ -2610,7 +2610,7 @@ static int mem_cgroup_force_empty(struct mem_cgroup *memcg) if (signal_pending(current)) return -EINTR; - progress = try_to_free_mem_cgroup_pages(memcg, 1, + progress = try_to_free_mem_cgroup_pages(memcg, 1024, GFP_KERNEL, true); if (!progress) { nr_retries--; -- 2.11.0 -- To unsubscribe from this list: send the line "unsubscribe cgroups" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html