Re: [Lhms-devel] [PATCH 0/7] Fragmentation Avoidance V19

Dave Hansen
2005-11-02T12:43:03Z

On Wed, 2005-11-02 at 13:00 +0100, Ingo Molnar wrote:
>
> > Yeah - and that isn't what is being proposed here. The goal is to
> > ask the kernel to identify some memory which can be legitimately
> > freed and hasten the freeing of that memory.
>
> but that's very easy to identify: check the free list or the clean
> list(s). No defragmentation necessary. [unless the unit of RAM mapping
> between hypervisor and guest is too coarse (i.e. not 4K pages).]

It needs to be that coarse in cases where HugeTLB is desired for use.
I'm not sure I could convince the DB guys to give up large pages,
they're pretty hooked on them. ;)

-- Dave