Re: [PATCH v5] mm: Add memory allocation watchdog kernel thread.

From: Michal Hocko
Date: Thu May 12 2016 - 12:38:32 EST


On Fri 13-05-16 00:09:07, Tetsuo Handa wrote:
[...]
> Michal, this version eliminated overhead of walking the process list
> when nothing is wrong. You are aware of the possibility of
> debug_show_all_locks() failing to report the culprit, aren't you?
> So, what are unacceptable major problems for you?

I do not remember complaining about anything unacceptable for this
patch. I just thought it was way too large the last time I have looked
at it. Johannes was suggesting to simply extend warn_alloc_failed to
also report too many retries with some extended information as a more
lightweight approach. It wouldn't give as much information as your
watchdog but maybe it would be sufficient to figure out that something
really bad is going on. Dunno but I would rather see a more lightweight
debugging aid than a lot of code which sit basically unused most of the
time.

That being said I cannot comment on this particular version as I haven't
checked it properly yet.
--
Michal Hocko
SUSE Labs