Re: Page allocator: Single Zone optimizations

Andrew Morton
2006-11-02T22:11:44Z

On Thu, 02 Nov 2006 22:03:30 +0000
Andy Whitcroft <apw@shadowen.org> wrote:

> >> On it's own lumpy-reclaim or linear-reclaim were not enough to get
> >> MAX_ORDER_NR_PAGES blocks of contiguous pages and these were of interest
> >> for huge pages although not necessarily of much use to memory hot-unplug.
> >
> > I'm interested in lumpy-reclaim as a simple solution to the
> > e1000-cant-allocate-an-order-2-page problem, rather than for hugepages.
> >
> > ie: a bugfix, not a feature..
>
>
> Is there a description of the problem and particularly of the
> allocation patterns here.

I guess we see maybe a couple of reports a month. The driver tries to
allocate an order-2 patch from atomic context and there aren't any so a
warning gets spat out and people complain. The usual "fix" is to increase
min_free_kbytes. Try executing google(e1000 min_free_kbytes);