Hello, Glauber.

On Wed, Oct 31, 2012 at 09:38:32PM +0400, Glauber Costa wrote:

Because I am allocating an array big enough to hold one entry per memcg.
The natural array index for this, is the css_id. Obviously, I don't want
this array to have 65k entries in size, so I resize it (doubling every
time) Because I don't know the css_id at this time, I have to do it later.

Another option for this - which I also considered - would be to use a
different index. We get more packing, since not all memcgs will be kmem
limited (and the index would contain only the kmem limited memcgs), and
we can allocate this index during ->create().

I initially picked the css_index because I though a specialized index
might be confusing. But if you feel strongly about all the allocations
happening inside ->create(), this would be a way to avoid it. Would you
prefer that?

I'll think more about it.  The whole css_id thing might need some soul
searching too anyway.  Let's continue this one your patch thread.

Thanks.

-- 
tejun