Re: [PATCH v2 1/3] misc_cgroup: introduce misc.events and misc_events.local

From: Vipin Sharma
Date: Tue Sep 14 2021 - 16:11:09 EST


On Mon, Sep 13, 2021 at 7:24 PM brookxu <brookxu.cn@xxxxxxxxx> wrote:
>
> Thanks for your time.
>
> Vipin Sharma wrote on 2021/9/14 12:51 上午:
> > On Sun, Sep 12, 2021 at 10:01 PM brookxu <brookxu.cn@xxxxxxxxx> wrote:
> >>
> >> From: Chunguang Xu <brookxu@xxxxxxxxxxx>
> >>
> >> Introduce misc.events and misc.events.local to make it easier for
> >
> > I thought Tejun only gave go ahead for misc.events and not for
> > misc.events.local.
> >
>
> Maybe I missed something. I think events.local is somewhat useful. For
> example, the events of node A is large. If we need to determine whether
> it is caused by the max of node A, if there is no events.local, then we
> need to traverse the events of the child nodes and compare them with
> node A. This is a bit complicated. If there is events.local, we can do
> it very easily. Should we keep the events.local interface?

Tejun mentioned in his previous email that he prefers the hierarchical
one. https://lore.kernel.org/lkml/YTuX6Cpv1kg+DHmJ@xxxxxxxxxxxxxxx/

I agree with you that it's easier to identify the constraint cgroup
with the local file. However, there is one downside also, which is if
a cgroup gets deleted then that local information is lost, we will
need a hierarchical reporting to observe the resource constraint. I
will be fine with both files but if I have to choose one I am now more
inclined towards hierarchical (events).

Thanks
Vipin