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Date: Wed, 30 Nov 2016 10:21:44 -0800
From: Marc MERLIN <marc@merlins.org>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Kent Overstreet <kent.overstreet@gmail.com>, Tejun Heo <tj@kernel.org>,
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Subject: Re: 4.8.8 kernel trigger OOM killer repeatedly when I have lots of
 RAM that should be free
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On Wed, Nov 30, 2016 at 10:14:50AM -0800, Linus Torvalds wrote:
> Anyway, none of this seems new per se. I'm adding Kent and Jens to the
> cc (Tejun already was), in the hope that maybe they have some idea how
> to control the nasty worst-case behavior wrt workqueue lockup (it's
> not really a "lockup", it looks like it's just hundreds of workqueues
> all waiting for IO to complete and much too deep IO queues).
 
I'll take your word for it, all I got in the end was
Kernel panic - not syncing: Hard LOCKUP
and the system stone dead when I woke up hours later.

> And I think your NMI watchdog then turns the "system is no longer
> responsive" into an actual kernel panic.

Ah, I see.

Thanks for the reply, and sorry for bringing in that separate thread
from the btrfs mailing list, which effectively was a suggestion similar
to what you're saying here too.

Marc
-- 
"A mouse is a device used to point at the xterm you want to type in" - A.S.R.
Microsoft is to operating systems ....
                                      .... what McDonalds is to gourmet cooking
Home page: http://marc.merlins.org/                         | PGP 1024R/763BE901