On Fri, Aug 18, 2017 at 9:53 AM, Liang, Kan <kan.liang@xxxxxxxxx> wrote: > >> On Fri, Aug 18, 2017 Mel Gorman wrote: >> >> That indicates that it may be a hot page and it's possible that the page is >> locked for a short time but waiters accumulate. What happens if you leave >> NUMA balancing enabled but disable THP? > > No, disabling THP doesn't help the case. Interesting. That particular code sequence should only be active for THP. What does the profile look like with THP disabled but with NUMA balancing still enabled? Just asking because maybe that different call chain could give us some other ideas of what the commonality here is that triggers out behavioral problem. I was really hoping that we'd root-cause this and have a solution (and then apply Tim's patch as a "belt and suspenders" kind of thing), but it's starting to smell like we may have to apply Tim's patch as a band-aid, and try to figure out what the trigger is longer-term. Linus -- 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>