CAMBRIA and more than one atheros card

[Adrian Chadd]

On 7 July 2014 11:28, John Hay <jhay at meraka.org.za> wrote:
> On Mon, Jul 07, 2014 at 11:22:46AM -0700, Adrian Chadd wrote:
>> On 7 July 2014 10:12, Ian Lepore <ian at freebsd.org> wrote:
>> > On Mon, 2014-07-07 at 09:25 -0700, Adrian Chadd wrote:
>> >> hi,
>> >>
>> >> That call is returning ENOMEM. I'm not sure why. It allocated an mbuf
>> >> fine, but it couldn't allocate the DMA map.
>> >>
>> >> What's the output of "vmstat -z" ? I wonder if it's failing an allocation.
>> >>
>> >>
>> >>
>> >> -a
>> >
>> > Lack of bounce buffers is a posibility that won't show up in vmstat
>> > output.
>>
>> right, but there's a bunch of already failing vmstat entries.
>>
>>
>> John - there's a vmscale parameter somewhere. Hiren had to drop it
>> down for his APs to work in 64MB of RAM. I think it's
>> vm.kmem_size_scale . What's it say for you?
>>
>
> :~ # sysctl vm.kmem_size_scale
> vm.kmem_size_scale: 3

Ok. Search the archives for an email from Hiren titled "mbuf autotuning effect".

TL;DR - set it to 1 and recompile. There's a kernel option somewhere
to do exactly that.



-a