At 09/20/2012 04:17 AM, Minchan Kim Wrote: > Hi KOSAKI, > > On Wed, Sep 19, 2012 at 02:05:20PM -0400, KOSAKI Motohiro wrote: >> On Wed, Sep 19, 2012 at 3:29 AM, Minchan Kim <minchan@xxxxxxxxxx> wrote: >>> During memory-hotplug stress test, I found NR_ISOLATED_[ANON|FILE] >>> are increasing so that kernel are hang out. >>> >>> The cause is that when we do memory-hotadd after memory-remove, >>> __zone_pcp_update clear out zone's ZONE_STAT_ITEMS in setup_pageset >>> without draining vm_stat_diff of all CPU. >>> >>> This patch fixes it. >> >> zone_pcp_update() is called from online pages path. but IMHO, >> the statistics should be drained offline path. isn't it? > > It isn't necessary because statistics is right until we reset it to zero > in online path. > Do you have something on your mind that we have to drain it in offline path? When a node is offlined and onlined again. We create node_data[i] in the function hotadd_new_pgdat(), and we will lost the statistics stored in zone->pageset. So we should drain it in offline path. Thanks Wen Congyang > >> >> thanks. > -- 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/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>