[Devel] Re: Fork bomb limitation in memcg WAS: Re: [PATCH 00/11] kmem controller for memcg: stripped down version

[Glauber Costa]

On 06/27/2012 04:29 PM, Frederic Weisbecker wrote:
> On Wed, Jun 27, 2012 at 01:29:04PM +0400, Glauber Costa wrote:
>> On 06/27/2012 01:55 AM, Andrew Morton wrote:
>>>> I can't speak for everybody here, but AFAIK, tracking the stack through
>>>> the memory it used, therefore using my proposed kmem controller, was an
>>>> idea that good quite a bit of traction with the memcg/memory people.
>>>> So here you have something that people already asked a lot for, in a
>>>> shape and interface that seem to be acceptable.
>>>
>>> mm, maybe.  Kernel developers tend to look at code from the point of
>>> view "does it work as designed", "is it clean", "is it efficient", "do
>>> I understand it", etc.  We often forget to step back and really
>>> consider whether or not it should be merged at all.
>>>
>>> I mean, unless the code is an explicit simplification, we should have
>>> a very strong bias towards "don't merge".
>>
>> Well, simplifications are welcome - this series itself was
>> simplified beyond what I thought initially possible through the
>> valuable comments
>> of other people.
>>
>> But of course, this adds more complexity to the kernel as a whole.
>> And this is true to every single new feature we may add, now or in
>> the
>> future.
>>
>> What I can tell you about this particular one, is that the justification
>> for it doesn't come out of nowhere, but from a rather real use case that
>> we support and maintain in OpenVZ and our line of products for years.
> 
> Right and we really need a solution to protect against forkbombs in LXC.
Small correction: In containers. LXC is not the only one out there =p