On Thu, 28 Apr 2011 10:49:12 +0900 KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx> wrote: > On Thu, 28 Apr 2011 10:37:05 +0900 > Daisuke Nishimura <nishimura@xxxxxxxxxxxxxxxxx> wrote: > > > + if (time_after(mem->next_scan_node_update, jiffies)) > > > + return; > > > + > > Shouldn't it be time_before() or time_after(jiffies, next_scan_node_update) ? > > > > Looks good to me, otherwise. > > > > time_after(a, b) returns true when a is after b.....you're right. > == > Now, memory cgroup's direct reclaim frees memory from the current node. > But this has some troubles. In usual, when a set of threads works in > cooperative way, they are tend to on the same node. So, if they hit > limits under memcg, it will reclaim memory from themselves, it may be > active working set. > > For example, assume 2 node system which has Node 0 and Node 1 > and a memcg which has 1G limit. After some work, file cacne remains and > and usages are > Node 0: 1M > Node 1: 998M. > > and run an application on Node 0, it will eats its foot before freeing > unnecessary file caches. > > This patch adds round-robin for NUMA and adds equal pressure to each > node. When using cpuset's spread memory feature, this will work very well. > > But yes, better algorithm is appreciated. > > From: Ying Han <yinghan@xxxxxxxxxx> > Signed-off-by: Ying Han <yinghan@xxxxxxxxxx> > Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx> > Acked-by: Daisuke Nishimura <nishimura@xxxxxxxxxxxxxxxxx> -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>