Michal Hocko wrote: > On Mon 12-12-16 12:49:03, Petr Mladek wrote: > > On Mon 2016-12-12 10:07:03, Michal Hocko wrote: > > > On Sat 10-12-16 20:24:57, Tetsuo Handa wrote: > [...] > > > > The introduction of uncontrolled > > > > > > > > warn_alloc(gfp_mask, "page allocation stalls for %ums, order:%u", ...); > > > > I am just curious that there would be so many messages. > > If I get it correctly, this warning is printed > > once every 10 second. Or am I wrong? > > Yes it is once per 10s per allocation context. Tetsuo's test case is > generating hundreds of such allocation paths which are hitting the > warn_alloc path. So they can meet there and generate a lot of output. Excuse me, but most processes in this testcase ( http://lkml.kernel.org/r/201612080029.IBD55588.OSOFOtHVMLQFFJ@xxxxxxxxxxxxxxxxxxx ) are blocked on locks. I guess at most few dozens of threads are in allocation paths. It would be possible to try to keep as many threads as possible inside allocation paths if I try different test cases. But not so interesting thing for a system with only 4 CPUs. Maybe interesting if 256 CPUs or more... -- 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>