Re: cgroup: status-quo and userland efforts

[Li Zefan <lizefan-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>]

On 2013/4/6 9:21, Tejun Heo wrote:
> Hello, guys.
> 
>  Status-quo
>  ==========
> 
> It's been about a year since I wrote up a summary on cgroup status quo
> and future plans.  We're not there yet but much closer than we were
> before.  At least the locking and object life-time management aren't
> crazy anymore and most controllers now support proper hierarchy
> although not all of them agree on how to treat inheritance.
> 
> IIRC, the yet-to-be-converted ones are blk-throttle and perf.  cpu
> needs to be updated so that it at least supports a similar mechanism
> as cfq-iosched for configuring ratio between tasks on an internal
> cgroup and its children.  Also, we really should update how cpuset
> handles a cgroup becoming empty (no cpus or memory node left due to
> hot-unplug).  It currently transfers all its tasks to the nearest
> ancestor with executing resources, which is an irreversible process
> which would affect all other co-mounted controllers.  We probably want
> it to just take on the masks of the ancestor until its own executing
> resources become online again, and the new behavior should be gated
> behind a switch (Li, can you please look into this?).
> 

Sure, I'll be working on sane hierarchy behavior for cpuset.