Re: Cache Allocation Technology Design

Vikas Shivappa
2014-10-29T17:41:49Z

On Wed, 29 Oct 2014, Peter Zijlstra wrote:

> On Wed, Oct 29, 2014 at 04:32:04PM +0000, Auld, Will wrote:
>> I maybe repeating what Peter has just said but for elements in the
>> hierarchy where the mask is the same as its parents mask there is no
>> need for a separate CLOS even in the case where there are tasks in the
>> group. So we can inherit the CLOS of the parent until which time both
>> the mask is different than the parent and there are tasks in the
>> group.
>
> I did not state that explicitly, but I did think about that. We could
> still wait to allocate a CLOS until at least one such group acquires a
> task.
>

Was wondering if it is a requirement of the 'full hierarchy' for the
child to inherit the cbm of parent ? .
Alternately we can allocate the CLOSid when a cgroup
is created and have an empty cbm - but dont let the tasks to be added
unless the user assigns a cbm. Cpuset does something similar where
its necessary to set the cpu mask(empty by default) of a cgroup before adding
tasks.