Re: [RFC] [PATCH -mm] cgroup: limit the amount of dirty file pages

Andrea Righi
2008-09-10T07:26:55Z

Dave Hansen wrote:
> On Tue, 2008-09-09 at 17:38 +0200, Andrea Righi wrote:
>> It allows to control how much dirty file pages a cgroup can have at any
>> given time. This feature is supposed to be strictly connected to a
>> generic cgroup IO controller (see below).
>
> So, this functions similarly to our global dirty ratio? Is it just
> intended to keep a cgroup from wedging itself too hard with too many
> dirty pages, just like the global ratio?
>
> -- Dave

Correct, it's the same functionality provided by vm.dirty_ratio and
vm.dirty_background_ratio, except that is intended to be per-cgroup.

Without this functionality, a cgroup can even dirty all its memory,
allocated by the memory controller, since statistics and writeback
configurations are global.

-Andrea