Re: Respin: [PATCH] mm: limit lowmem_reserve

[Andrew Morton]

Con Kolivas <kernel@xxxxxxxxxxx> wrote:
>
> On Thursday 06 April 2006 12:55, Con Kolivas wrote:
> > On Thursday 06 April 2006 12:43, Andrew Morton wrote:
> > > Con Kolivas <kernel@xxxxxxxxxxx> wrote:
> > > > It is possible with a low enough lowmem_reserve ratio to make
> > > >  zone_watermark_ok fail repeatedly if the lower_zone is small enough.
> > >
> > > Is that actually a problem?
> >
> > Every single call to get_page_from_freelist will call on zone reclaim. It
> > seems a problem to me if every call to __alloc_pages will do that?
> 
> every call to __alloc_pages of that zone I mean
> 

One would need to check with the NUMA guys.  zone_reclaim() has a
(lame-looking) timer in there to prevent it from doing too much work.

That, or I'm missing something.  This problem wasn't particularly well
described, sorry.
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