Re: [stable] OOM-killer invoked but why ?

[Greg KH <greg@kroah.com>]

On Tue, Feb 05, 2008 at 04:33:03PM +0530, Dhaval Giani wrote:
> On Tue, Feb 05, 2008 at 02:07:37AM -0800, Andrew Morton wrote:
> > On Thu, 31 Jan 2008 13:53:05 +0100 Claude Frantz <r31dmaeu@pc0312b.rz.unibw-muenchen.de> wrote:
> > 
> > > Hello !
> > > 
> > > I'm faced to a problem where the OOM-killer is invoked but I cannot find
> > > the reason why. The machine is rather powerfull, the load is very moderate,
> > > the disk swap space is nearly unused. The only strange observation which
> > > appears to me is the slow but progressive decreasing of kbbuffers during
> > > many hours.
> > > 
> > > Can you help me to diagnose the problem and to find a good solution ?
> > > 
> > > ...
> > >
> > > Jan 28 03:50:49 toaster kernel: 177466 pages slab
> > > Jan 28 03:50:49 toaster kernel: 1915 pages pagetables
> > > Jan 28 03:50:49 toaster kernel: Out of memory: kill process 10859 (amavisd) score 36218 or a child
> > > Jan 28 03:50:49 toaster kernel: Killed process 19146 (amavisd)
> > 
> > slab.  Maybe you've been bitten by the quicklist leak.  If you're able to
> > patch your kernel then please try this fix:
> > 
> > commit 96990a4ae979df9e235d01097d6175759331e88c
> > Author: Christoph Lameter <clameter@sgi.com>
> > Date:   Mon Jan 14 00:55:14 2008 -0800
> > 
> >     quicklists: Only consider memory that can be used with GFP_KERNEL
> >     
> >     Quicklists calculates the size of the quicklists based on the number of
> >     free pages.  This must be the number of free pages that can be allocated
> >     with GFP_KERNEL.  node_page_state() includes the pages in ZONE_HIGHMEM and
> >     ZONE_MOVABLE which may lead the quicklists to become too large causing OOM.
> >     
> >     Signed-off-by: Christoph Lameter <clameter@sgi.com>
> >     Tested-by: Dhaval Giani <dhaval@linux.vnet.ibm.com>
> >     Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
> >     Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
> > 
> > diff --git a/mm/quicklist.c b/mm/quicklist.c
> > index ae8189c..3f703f7 100644
> > --- a/mm/quicklist.c
> > +++ b/mm/quicklist.c
> > @@ -26,9 +26,17 @@ DEFINE_PER_CPU(struct quicklist, quicklist)[CONFIG_NR_QUICK];
> >  static unsigned long max_pages(unsigned long min_pages)
> >  {
> >  	unsigned long node_free_pages, max;
> > +	struct zone *zones = NODE_DATA(numa_node_id())->node_zones;
> > +
> > +	node_free_pages =
> > +#ifdef CONFIG_ZONE_DMA
> > +		zone_page_state(&zones[ZONE_DMA], NR_FREE_PAGES) +
> > +#endif
> > +#ifdef CONFIG_ZONE_DMA32
> > +		zone_page_state(&zones[ZONE_DMA32], NR_FREE_PAGES) +
> > +#endif
> > +		zone_page_state(&zones[ZONE_NORMAL], NR_FREE_PAGES);
> > 
> > -	node_free_pages = node_page_state(numa_node_id(),
> > -			NR_FREE_PAGES);
> >  	max = node_free_pages / FRACTION_OF_NODE_MEM;
> >  	return max(max, min_pages);
> >  }
> > 
> > 
> > I note that this didn't have the stable@kernel.org cc.  Christoph, did we
> > deliberately decide not to backport?
> > 
> 
> According to
> http://archive.netbsd.se/?ml=linux-stable-commits&a=2008-01&m=6134301 ,
> its been added to the stable tree. I remember asking Greg to add it.

And then Christoph told me to remove it...

thanks,

greg k-h