On Mon, 5 Dec 2011 07:32:33 -0200
Glauber Costa<glommer@xxxxxxxxxxxxx> wrote:
Hi,
Specially Peter and Paul, but all the others:
As you can see in https://lkml.org/lkml/2011/12/4/178, and in my answer
to that, there is a question - one I've asked before but without that
much of an audience - of whether /proc files read from process living on
cgroups should display global or per-cgroup resources.
In the past, I was arguing for a knob to control that, but I recently
started to believe that a knob here will only overcomplicate matters:
if you live in a cgroup, you should display only the resources you can
possibly use. Global is for whoever is in the main cgroup.
Hm. I have a suggestion and a concern.
(A suggestion)
How about having a mount option for procfs ?
For example,
mount -t proc .... -o cgroup_virtualized
Then, /proc/stat etc shows per-cgroup information.
(A concern)
/proc/stat will be a mixture of virtualized values and not-virtualized values.
1. Don't users need to know whether each value is virtualized or not ?
2. Can we have a way to show "this value is virtualized!" annotation ?
Please note again that I don't necessarily dislike the idea of a mount option, if we must do something. I just don't see the point.
Now, it comes two questions:I think some kind of care for users are required as I wrote above.
1) Do you agree with that, for files like /proc/stat ? I think the most
important part is to be consistent inside the system, regardless of what
is done
Let's keep in mind that there are more to the story, and I want to be sure to address everyones PoVs here. The impression I've got is that the reasons to keep cpuacct around came mainly from 2 sources:2) Will cpuacct stay? I think if it does, that becomes almost mandatory
(at least the bind mount idea is pretty much over here), because drawing
value for /proc/stat becomes quite complex.
The cpuacct cgroup can provide user, sys, etc values. But we also have:
If virtualized /proc/stat works, I don't think 'account only' cgroup is
necessary. It can be obsolete.