On Tue, 21 Sep 2010 12:18:18 -0400 Rik van Riel <riel@xxxxxxxxxx> wrote: > Atomic allocations cannot fall back to the page eviction code > and are expected to fail. In fact, in some network intensive > workloads, it is common to experience hundreds of GFP_ATOMIC > allocation failures. > > Printing out a backtrace for every one of those expected > allocation failures accomplishes nothing good. At multi-gigabit > network speeds with jumbo frames, a burst of allocation failure > backtraces could even slow down the system. > > We're better off not printing out backtraces on GFP_ATOMIC > allocation failures. > > Signed-off-by: Rik van Riel <riel@xxxxxxxxxx> > > diff --git a/include/linux/gfp.h b/include/linux/gfp.h > index 975609c..5a0bddb 100644 > --- a/include/linux/gfp.h > +++ b/include/linux/gfp.h > @@ -72,7 +72,7 @@ struct vm_area_struct; > /* This equals 0, but use constants in case they ever change */ > #define GFP_NOWAIT (GFP_ATOMIC & ~__GFP_HIGH) > /* GFP_ATOMIC means both !wait (__GFP_WAIT not set) and use emergency pool */ > -#define GFP_ATOMIC (__GFP_HIGH) > +#define GFP_ATOMIC (__GFP_HIGH | __GFP_NOWARN) > #define GFP_NOIO (__GFP_WAIT) > #define GFP_NOFS (__GFP_WAIT | __GFP_IO) > #define GFP_KERNEL (__GFP_WAIT | __GFP_IO | __GFP_FS) A much finer-tuned implementation would be to add __GFP_NOWARN just to the networking call sites. I asked about this in June and it got nixed: http://www.spinics.net/lists/netdev/msg131965.html -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>