On Wed, May 18, 2011 at 10:30 PM, KAMEZAWA Hiroyuki
[off-list ref] wrote:

On Wed, 18 May 2011 22:15:53 -0400
Andrew Lutomirski [off-list ref] wrote:

quoted

On Wed, May 18, 2011 at 1:17 AM, Minchan Kim [off-list ref] wrote:

quoted

On Wed, May 18, 2011 at 4:22 AM, Andrew Lutomirski [off-list ref] wrote:

quoted

quoted

Andrew, Could you test this patch with !pgdat_balanced patch?
I think we shouldn't see OOM message if we have lots of free swap space.

== CUT_HERE ==

diff --git a/mm/vmscan.c b/mm/vmscan.c
index f73b865..cc23f04 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c

@@ -1341,10 +1341,6 @@ static inline bool

should_reclaim_stall(unsigned long nr_taken,
       if (current_is_kswapd())
               return false;

-       /* Only stall on lumpy reclaim */
-       if (sc->reclaim_mode & RECLAIM_MODE_SINGLE)
-               return false;
-
       /* If we have relaimed everything on the isolated list, no stall */
       if (nr_freed == nr_taken)
               return false;



Then, if you don't see any unnecessary OOM but still see the hangup,
could you apply this patch based on previous?

With this patch, I started GNOME and Firefox, turned on swap, and ran
test_mempressure.sh 1500 1400 1.  Instant panic (or OOPS and hang or
something -- didn't get the top part).  Picture attached -- it looks
like memcg might be involved.  I'm running F15, so it might even be
doing something.

Hmm, what kernel version do you use ?
I think memcg is not guilty because RIP is shrink_page_list().
But ok, I'll dig this. Could you give us your .config ?

Attached.

The address in shrink_page_list is ud2, from (I think)
VM_BUG_ON(PageActive(page));.  The sequence is:

   0xffffffff810d24cc <+202>:	callq  0xffffffff810cf930 <test_and_set_bit>
   0xffffffff810d24d1 <+207>:	test   %eax,%eax
   0xffffffff810d24d3 <+209>:	jne    0xffffffff810d2aa5 <shrink_page_list+1699>
   0xffffffff810d24d9 <+215>:	mov    -0x28(%rbx),%rax
   0xffffffff810d24dd <+219>:	test   $0x40,%al
   0xffffffff810d24df <+221>:	je     0xffffffff810d24e3 <shrink_page_list+225>
   0xffffffff810d24e1 <+223>:	ud2


--Andy