Re: OOM killer invoked during btrfs send/recieve on otherwise idle machine

From: Michal Hocko
Date: Fri Aug 19 2016 - 09:29:30 EST


On Tue 02-08-16 09:48:01, Chris Murphy wrote:
> On Tue, Aug 2, 2016 at 9:38 AM, Chris Murphy <lists@xxxxxxxxxxxxxxxxx> wrote:
> > Yesterday I saw oom killer knocking off processes during a simple cp
> > -a from one Btrfs to another, in a VM, with kernel
> > 4.8.0-0.rc0.git3.1.fc25.x86_64. The call trace looks different than
> > Markus' so I'm not sure it's the same problem. It's not always
> > reproducible. It hasn't happened on 4.7.0 though. According ot koji
> > this is Linux v4.7-6438-gc624c86
> >
> > This is 'journalctl -o short-monotonic -b-4 -k'
> >
> > https://drive.google.com/open?id=0B_2Asp8DGjJ9ZC1JSDJnaWpnSEE
>
> Btrfs volume 2 is created at [ 625.769736] and mounted at [
> 640.119150], with the copy starting shortly after that. OOM happens at
> [ 856.212658] . There are a bunch of earlier bug messages, BUG:
> sleeping function called from invalid context at mm/slab.h:393.

It seems that the current linux-next +
http://lkml.kernel.org/r/f7a9ea9d-bb88-bfd6-e340-3a933559305a@xxxxxxx
seems like helped other users. Could you try this as well please?
--
Michal Hocko
SUSE Labs