Arkadiusz Miskiewicz wrote: > > > vmstat_update() and submit_flushes() remained pending for about 110 > > > seconds. If xlog_cil_push_work() were spinning inside GFP_NOFS > > > allocation, it should be reported as MemAlloc: traces, but no such lines > > > are recorded. I don't know why xlog_cil_push_work() did not call > > > schedule() for so long. Anyway, applying > > > http://lkml.kernel.org/r/20151111160336.GD1432@xxxxxxxxxxxxxx should > > > solve vmstat_update() part. > > > > To apply that patch on top of 4.1.13 I also had to apply patches listed > > below. > > > > So in summary appllied: > > http://sprunge.us/GYBb > > http://sprunge.us/XWUX > > http://sprunge.us/jZjV > > I've tried more to trigger "page allocation failure" with usual actions that > triggered it previously but couldn't reproduce. With these patches applied it > doesn't happen. > > Logs from my tests: > > http://ixion.pld-linux.org/~arekm/log-mm-3.txt.gz > http://ixion.pld-linux.org/~arekm/log-mm-4.txt.gz (with swap added) > Good. vmstat_update() and submit_flushes() are no longer pending for long. log-mm-4.txt:Nov 14 16:40:08 srv kernel: [167753.393960] pending: vmstat_shepherd, vmpressure_work_fn log-mm-4.txt:Nov 14 16:40:08 srv kernel: [167753.393984] pending: submit_flushes [md_mod] log-mm-4.txt:Nov 14 16:41:08 srv kernel: [167813.439405] pending: submit_flushes [md_mod] log-mm-4.txt:Nov 14 17:17:19 srv kernel: [169985.104806] pending: vmstat_shepherd I think that the vmstat statistics now have correct values. > But are these patches solving the problem or just hiding it? > Excuse me but I can't judge. If you are interested in monitoring how vmstat statistics are changing under stalled condition, you can try below patch. diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 35a46b4..3de3a14 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -2794,8 +2794,7 @@ static int kmallocwd(void *unused) rcu_read_unlock(); preempt_enable(); show_workqueue_state(); - if (dump_target_pid <= 0) - dump_target_pid = -pid; + show_mem(0); /* Wait until next timeout duration. */ schedule_timeout_interruptible(kmallocwd_timeout); if (memalloc_counter[index]) -- 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>