Re: [External] Re: [PATCH v15 4/8] mm: hugetlb: alloc the vmemmap pages associated with each HugeTLB page

From: Michal Hocko
Date: Tue Feb 16 2021 - 03:24:22 EST


On Tue 16-02-21 09:13:09, David Hildenbrand wrote:
> On 15.02.21 20:02, Michal Hocko wrote:
> > Would it be feasible to reused parts of the freed page in
> > the worst case?
>
> As already discussed, this is only possible when the huge page does not
> reside on ZONE_MOVABLE/CMA.

Right. But usually this is not the case so it would be at least
something.

> In addition, we can no longer form a huge page at that memory location ever.

Yes, that's why I am saying in the worst case. E.g. when dissolving is
really necessary like in hwpoison case.

Maybe we are really far from needing something like that. I just wanted
to mention this option and I was not aware this has been discussed
previously.
--
Michal Hocko
SUSE Labs