On Fri, Apr 27, 2012 at 3:14 PM, Ying Han <yinghan@xxxxxxxxxx> wrote: > We have the nr_mlock stat both in meminfo as well as vmstat system wide, this > patch adds the mlock field into per-memcg memory stat. The stat itself enhances > the metrics exported by memcg since the unevictable lru includes more than > mlock()'d page like SHM_LOCK'd. > > Why we need to count mlock'd pages while they are unevictable and we can not > do much on them anyway? > > This is true. The mlock stat I am proposing is more helpful for system admin > and kernel developer to understand the system workload. The same information > should be helpful to add into OOM log as well. Many times in the past that we > need to read the mlock stat from the per-container meminfo for different > reason. Afterall, we do have the ability to read the mlock from meminfo and > this patch fills the info in memcg. > > Note: > Here are the places where I didn't add the hook: > 1. in the mlock_migrate_page() since the owner of oldpage and newpage is the same. > 2. in the freeing path since page shouldn't get to there at the first place. Looks good. (even though I don't like unreliable mlock statistics) Acked-by: KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx> -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. 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>