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

Linus Torvalds
2005-11-03T19:35:28Z

On Thu, 3 Nov 2005, Martin J. Bligh wrote:
>
> Possibly, I can redo the calculations easily enough (have to go for now,
> but I just sent the other ones). But we don't keep a fixed percentage of
> memory free - we cap it ... perhaps we should though?

I suspect the capping may well be from some old HIGHMEM interaction on x86
(ie "don't keep half a gig free in the normal zone just because we have
16GB in the high-zone". We used to have serious balancing issues, and I
wouldn't be surprised at all if there are remnants from that. Stuff that
simply hasn't been visible, because not a lot of people had many many GB
of memory even on machines that didn't need HIGHMEM.

Linus