Re: cgroup, RT reservation per core(s)?

[Rolando Martins <rolando.martins@gmail.com>]

Thanks for the quick reply.

On Mon, Feb 9, 2009 at 7:52 PM, Peter Zijlstra <peterz@infradead.org> wrote:
> On Mon, 2009-02-09 at 19:30 +0000, Rolando Martins wrote:
>> Hi,
>> I would like to have in a quad-core, 2 cores totally (100%) dedicated
>> to RT tasks (SCHED_RR and SCHED_FIFO) and the other 2 cores with
>> normal behavior, better said,  allowing SCHED_OTHER & SCHED_FIFO &
>> SCHED_RR tasks but still with a RT reservation. Follows an example:
>>
>>
>> # Setup first domain (cpu 0,1)
>> echo 0-1 > /dev/cgroup/0/cpuset.cpus
>> echo 0 > /dev/cgroup/0/cpuset.mems
>>
>> # Setup RT bandwidth for firstdomain (80% for RT, 20% others)
>> echo 1000000 > /dev/cgroup/0/cpu.rt_period_us
>> echo 800000 > /dev/cgroup/0/cpu.rt_runtime_us
>>
>>
>> # Setup second domain (cpu 2,3)
>> mkdir /dev/cgroup/1
>> echo 2-3 > /dev/cgroup/1/cpuset.cpus
>> echo 0 > /dev/cgroup/1/cpuset.mems
>>
>> # Setup RT bandwidth for second domain (100% for RT)
>> echo 1000000 > /dev/cgroup/1/cpu.rt_period_us
>> echo 1000000 > /dev/cgroup/1/cpu.rt_runtime_us
>>
>> Is there anyway for doing this?
>
> Nope, but why do you need bandwidth groups if all you want is a full
> cpu?
>
> Just the cpuset should be plenty
You have a point;)
>
>
I should have elaborated this more:

                     root
                  ----|----
                  |          |
(0.5 mem) 0         1 (100% rt, 0.5 mem)
                         ---------
                         |    |    |
                         2   3   4  (33% rt for each group, 33% mem
per group(0.165))
Rol