Re: Is it safe for kthreadd to drain_all_pages?

From: Michal Hocko
Date: Fri Apr 07 2017 - 12:39:44 EST


On Fri 07-04-17 09:25:33, Hugh Dickins wrote:
[...]
> 24 hours so far, and with a clean /var/log/messages. Not conclusive
> yet, and of course I'll leave it running another couple of days, but
> I'm increasingly sure that it works as you intended: I agree that
>
> mm-move-pcp-and-lru-pcp-drainging-into-single-wq.patch
> mm-move-pcp-and-lru-pcp-drainging-into-single-wq-fix.patch
>
> should go to Linus as soon as convenient. Though I think the commit
> message needs something a bit stronger than "Quite annoying though".
> Maybe add a line:
>
> Fixes serious hang under load, observed repeatedly on 4.11-rc.

Yeah, it is much less theoretical now. I will rephrase and ask Andrew to
update the chagelog and send it to Linus once I've got your final go.

Thanks!

--
Michal Hocko
SUSE Labs