Re: 4.8.8 kernel trigger OOM killer repeatedly when I have lots of RAM that should be free

From: Greg Kroah-Hartman
Date: Tue Nov 22 2016 - 11:37:57 EST


On Tue, Nov 22, 2016 at 05:14:02PM +0100, Vlastimil Babka wrote:
> On 11/22/2016 05:06 PM, Marc MERLIN wrote:
> > On Mon, Nov 21, 2016 at 01:56:39PM -0800, Marc MERLIN wrote:
> >> On Mon, Nov 21, 2016 at 10:50:20PM +0100, Vlastimil Babka wrote:
> >>>> 4.9rc5 however seems to be doing better, and is still running after 18
> >>>> hours. However, I got a few page allocation failures as per below, but the
> >>>> system seems to recover.
> >>>> Vlastimil, do you want me to continue the copy on 4.9 (may take 3-5 days)
> >>>> or is that good enough, and i should go back to 4.8.8 with that patch applied?
> >>>> https://marc.info/?l=linux-mm&m=147423605024993
> >>>
> >>> Hi, I think it's enough for 4.9 for now and I would appreciate trying
> >>> 4.8 with that patch, yeah.
> >>
> >> So the good news is that it's been running for almost 5H and so far so good.
> >
> > And the better news is that the copy is still going strong, 4.4TB and
> > going. So 4.8.8 is fixed with that one single patch as far as I'm
> > concerned.
> >
> > So thanks for that, looks good to me to merge.
>
> Thanks a lot for the testing. So what do we do now about 4.8? (4.7 is
> already EOL AFAICS).
>
> - send the patch [1] as 4.8-only stable. Greg won't like that, I expect.
> - alternatively a simpler (againm 4.8-only) patch that just outright
> prevents OOM for 0 < order < costly, as Michal already suggested.
> - backport 10+ compaction patches to 4.8 stable
> - something else?

Just wait for 4.8-stable to go end-of-life in a few weeks after 4.9 is
released? :)

thanks,

greg k-h