Re: [patch 3/9] mempool - Make mempools NUMA aware

Christoph Lameter
2006-01-27T00:57:06Z

On Thu, 26 Jan 2006, Matthew Dobson wrote:

> > We need this for other issues as well. f.e. to establish memory allocation
> > policies for the page cache, tmpfs and various other needs. Look at
> > mempolicy.h which defines a subset of what we need. Currently there is no
> > way to specify a policy when invoking the page allocator or slab
> > allocator. The policy is implicily fetched from the current task structure
> > which is not optimal.
>
> I agree that the current, task-based policies are subobtimal. Having to
> allocate and fill in even a small structure for each allocation is going to
> be a tough sell, though. I suppose most allocations could get by with a
> small handfull of static generic "policy structures"... This seems like it
> will turn into a signifcant rework of all the kernel's allocation routines,
> no small task. Certainly not something that I'd even start without
> response from some other major players in the VM area... Anyone?

No you would have a set of policies and only pass a pointer to the
policies to the allocator. I.e. have one emergency policy allocated
somewhere in the IP stack and then pass that to the allocator.

I guess that Andi Kleen and Paul Jackson would likely be interested in
such an endeavor.