On Sunday 15 of November 2015, Tetsuo Handa wrote: > 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. Here is log with this and all previous patches applied: http://ixion.pld-linux.org/~arekm/log-mm-5.txt.gz > > 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]) -- Arkadiusz Miśkiewicz, arekm / ( maven.pl | pld-linux.org ) _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs
