Re: Vanilla-Kernel 3 - page allocation failure

[Philipp Herz - Profihost AG <p.herz@profihost.ag>]

Am 19.10.2011 03:58, schrieb David Rientjes:
> On Tue, 18 Oct 2011, Andi Kleen wrote:
>
>> Philipp Herz - Profihost AG<p.herz@profihost.ag>  writes:
>>
>>> After updating kernel (x86_64) to stable version 3 there are a few
>>> messages appearing in the kernel log such as
>>>
>>> kworker/0:1: page allocation failure: order:1, mode:0x20
>>> mysql: page allocation failure: order:1, mode:0x20
>>> php5: page allocation failure: order:1, mode:0x20
>>
>> You just ran out of memory.
>>
>
> He ran out of order-1 physically contiguous memory and was unable to
> compact or reclaim because of the atomic context.
>
> Philipp, based on your pastes from another post, it's evident you're using
> CONFIG_SLAB and, unfortunately, it's not possible to change to single
> page allocations (which would only result in a page allocation failure if
> you were completely out of memory) without recompiling.
>
> You have a couple options:
>
>   - recompile with BREAK_GFP_ORDER_HI redefined to 0 in mm/slab.c, or
>
>   - recompile with CONFIG_SLUB instead of CONFIG_SLAB.
>
> It's very possible that neither of these will help, but it will tell you
> whether you need to go out and buy more RAM or not.  If you try to
> recompile with BREAK_GFP_ORDER_HI, these may turn into order-0
> allocations.  If you can't reboot, send the output of
> /proc/<pid>/net/protocols where<pid>  is the pid of one of the above tasks
> (kworker, mysql, php5) when they are running and we'll know.
>
>   [ Changing slab_break_gfp_order should really be a CONFIG_SLAB command-
>     line option.  It can't be runtime because slab depends on the order for
>     caches remaining constant, but we can certainly change it on boot. ]
>
> If you try CONFIG_SLUB instead of CONFIG_SLAB, you can pass
> slub_max_order=0 on the command line and see if it helps.

Hi David,

we have recompiled the kernel of one machine with CONFIG_SLUB instead of 
CONFIG_SLAB, but it is showing similar message.

Now it's showing failure at "order:5, mode:0x4020".

Call trace can be found at:
* http://pastebin.com/uGJiwvG1

Comparing kernel 2.6.32 (mm/page_alloc.c) there seams to be the same way 
of dealing with page allocation.

Do you have an idea why these (warning) messages do never appear running 
2.6.32?

Regards,
Philipp