On Wed 14-01-15 17:06:59, Vinayak Menon wrote: [...] > In one such instance, zone_page_state(zone, NR_ISOLATED_FILE) > had returned 14, zone_page_state(zone, NR_INACTIVE_FILE) > returned 92, and GFP_IOFS was set, and this resulted > in too_many_isolated returning true. But one of the CPU's > pageset vm_stat_diff had NR_ISOLATED_FILE as "-14". So the > actual isolated count was zero. As there weren't any more > updates to NR_ISOLATED_FILE and vmstat_update deffered work > had not been scheduled yet, 7 tasks were spinning in the > congestion wait loop for around 4 seconds, in the direct > reclaim path. Not syncing for such a long time doesn't sound right. I am not familiar with the vmstat syncing but sysctl_stat_interval is HZ so it should happen much more often that every 4 seconds. -- Michal Hocko SUSE Labs -- 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>