arm1136 with 2.6.29.5 running out of memory with 32k cache only, 16k and below is fine

arm1136 with 2.6.29.5 running out of memory with 32k cache only, 16k and below is fine

[koen velle]

Hi,

I've got a (simulated) system where I can select my cache sizes.  Boot
goes fine with 4, 8, and 16k cache, but goes boink with 32k cache.
While debugging, I'm able to find out that in __do_page_fault, I end
up at the label out_of_memory, as handle_mm_fault returns
VM_FAULT_OOM.

This does not happen with caches <32k.  Otherwise, both my system and
my linux config are identical, only the cache size is different.

Is there anything that can explain this ? Do I need to modify the
kernel configuration somehow if I want to use 32k caches ? Does the
kernel consume more memory when using 32k caches due to dealing with
cache coloring ?

In short, any easy answers ?

Thanks,

Koen.

Re: arm1136 with 2.6.29.5 running out of memory with 32k cache only, 16k and below is fine

[koen velle]

That should read ARM1176, not ARM1136, sorry for that... (but probably
does not make much difference)

Koen.

On Thu, Jul 29, 2010 at 10:14 AM, koen velle <koen.velle@gmail.com> wrote:
> Hi,
>
> I've got a (simulated) system where I can select my cache sizes.  Boot
> goes fine with 4, 8, and 16k cache, but goes boink with 32k cache.
> While debugging, I'm able to find out that in __do_page_fault, I end
> up at the label out_of_memory, as handle_mm_fault returns
> VM_FAULT_OOM.
>
> This does not happen with caches <32k.  Otherwise, both my system and
> my linux config are identical, only the cache size is different.
>
> Is there anything that can explain this ? Do I need to modify the
> kernel configuration somehow if I want to use 32k caches ? Does the
> kernel consume more memory when using 32k caches due to dealing with
> cache coloring ?
>
> In short, any easy answers ?
>
> Thanks,
>
> Koen.
>

Re: arm1136 with 2.6.29.5 running out of memory with 32k cache only, 16k and below is fine

[koen velle]

Dear all,

sorry for posting this to the wrong list, should have gone to
linux-arm-kernel, please ignore.

Koen.

On Thu, Jul 29, 2010 at 10:14 AM, koen velle <koen.velle@gmail.com> wrote:
> Hi,
>
> I've got a (simulated) system where I can select my cache sizes.  Boot
> goes fine with 4, 8, and 16k cache, but goes boink with 32k cache.
> While debugging, I'm able to find out that in __do_page_fault, I end
> up at the label out_of_memory, as handle_mm_fault returns
> VM_FAULT_OOM.
>
> This does not happen with caches <32k.  Otherwise, both my system and
> my linux config are identical, only the cache size is different.
>
> Is there anything that can explain this ? Do I need to modify the
> kernel configuration somehow if I want to use 32k caches ? Does the
> kernel consume more memory when using 32k caches due to dealing with
> cache coloring ?
>
> In short, any easy answers ?
>
> Thanks,
>
> Koen.
>