Re: [RFC PATCH 0/5] CFS load tracking trace events

[Dietmar Eggemann]

On 03/28/2017 12:05 PM, Vincent Guittot wrote:
> On 28 March 2017 at 08:35, Dietmar Eggemann <dietmar.eggemann@xxxxxxx> wrote:

[...]

> > The following keys are used to identify the cfs scheduler brick:
> >
> >  (1) Cpu number the cfs scheduler brick is attached to.
> >
> >  (2) Task_group path and (css) id.
> >
> >  (3) Task name and pid.
>
> Do you really need both path/name and id/pid ?
>
> The path/name looks quite intrusive so can't we just use id/pid ?

One problem is that all autogroups use id=0.

Another thing with task_groups is that dealing with path="/tg1/tg11" is 
so much more intuitive than id="7".

IMHO, we do need task name and pid to be able to clearly identify a task 
(same name/different pid or fork phase (forkee still has name of forker)).

You're right, the implementation with path is more complicated but I 
guess that's worth it. We could get rid of 'id' though.

[...]