Re: [Devel] Re: [RFC] libcg: design and plans

Balbir Singh
2008-03-05T11:49:56Z

Denis V. Lunev wrote:
> On Tue, 2008-03-04 at 22:15 -0800, Paul Menage wrote:
>> Hi Dhaval,
>>
>> On Tue, Mar 4, 2008 at 7:23 AM, Dhaval Giani <dhaval@linux.vnet.ibm.com> wrote:
>>> Hi,
>>>
>>> We have been working on a library for control groups which would provide
>>> simple APIs for programmers to utilize from userspace and make use of
>>> control groups.
>>>
>>> We are still designing the library and the APIs. I've attached the
>>> design (as of now) to get some feedback from the community whether we
>>> are heading in the correct direction and what else should be addressed.
>> There are a few things that it would be nice to include in such a
>> library, if you're going to develop one:
>>
>> - the ability to create abstract groups of processes, and resource
>> groups, and have the ability to tie these together arbitrarily. E.g
>> you might create abstract groups A, B and C, and be able to say that A
>> and B share memory with each other but not with C, and all three
>> groups are isolated from each other for CPU. Then libcg would mount
>> different resource types in different cgroup hierarchies (you would
>> probably tell it ahead of time which combinations of sharing you would
>> want, in order that it could minimize the number of mounted
>> hierarchies). When you tell libcg to move a process into abstract
>> group A, it would move it into the appropriate resource group in each
>> hierarchy.
>
> There is one more important thing. In addition to the processes you must
> unite or provide a way to unite other objects like sockets. This is
> needed to create a group-based socket buffer management.
>
> The mapping between socket and a process does not exists right now and,
> we can have (virtually), sockets from from different namespaces in one
> process.
>

Not sure how any of this is related to the library design we are discussing.
Your talking about writing a controller that groups based on sockets, that is a
totally different thing.

--
Warm Regards,
Balbir Singh
Linux Technology Center
IBM, ISTL