Re: cgroups(7): documenting cgroups v2 delegation

Michael Kerrisk (man-pages)
2018-01-10T22:24:05Z

Hello Tejun,

On 01/10/2018 11:14 PM, Tejun Heo wrote:
> Hello, Michael.
>
> On Wed, Jan 10, 2018 at 11:01:11PM +0100, Michael Kerrisk (man-pages) wrote:
>>>>>> Can you please confirm that it's only necessary to delegate this file
>>>>>> if we are delegating a threaded subtree?
>>>>>
>>>>> Replied on the other thread. The file isn't delegatable as far as I
>>>>> can tell.
>>>>
>>>> So, following on from the discussion in the other thread, my
>>>> question above still stands.
>>>
>>> Oh, I frankly haven't thought about delegating a threaded subtree.
>>
>> I'm still confused. cgroup-v2.txt documents the possibility. You
>> wrote that text. We just had a conversation in another thread about the
>> fact that cgroup.threads is delegatable. You must have thought at
>> least a little about this?
>
> Oh, I'm probably mixing up two things.
>
> 1. When delegating, cgroup.threads should be delegated. Doing that
> selectively doesn't achieve anything meaningful.

Understood. But surely delegating cgroup.threads is effectively
meaningless when delegating a "domain" cgroup tree? (Obviously it's
not harmful to delegate the the cgroup.threads file in this case;
it's just not useful to do so.)

> 2. I haven't thought much about delegating a sub-protion of a threaded
> subtree. Everything works the same way. I just can't think of a
> use case.

Ahhh -- now I see what you meant before.