Re: [PATCH] 1/5 VM changes: zone-pressure.patch

[Nikita Danilov]

Andrew Morton writes:
 > Nikita Danilov <[e-mail]> wrote:
 > >
 > > Add zone->pressure field. It estimates scanning intensity for this zone and
 > >  is calculated as exponentially decaying average of the scanning priority
 > >  required to free enough pages in this zone (mm/vmscan.c:zone_adj_pressure()).
 > > 
 > >  zone->pressure is supposed to be used in stead of scanning priority by
 > >  vmscan.c. This is used by later patches in a series.
 > > 
 > 
 > OK, fixes a bug.

What bug?

 > 
 > > 
 > >  diff -puN include/linux/mmzone.h~zone-pressure include/linux/mmzone.h
 > >  --- i386/include/linux/mmzone.h~zone-pressure	Wed Jul  9 12:24:50 2003
 > >  +++ i386-god/include/linux/mmzone.h	Wed Jul  9 12:24:50 2003
 > >  @@ -84,11 +84,23 @@ struct zone {
 > >   	atomic_t		refill_counter;
 > >   	unsigned long		nr_active;
 > >   	unsigned long		nr_inactive;
 > >  -	int			all_unreclaimable; /* All pages pinned */
 > >  +	int			all_unreclaimable:1; /* All pages pinned */
 > 
 > I'll revert this change.  Once we start adding bitfields in there they all
 > need common locking and it gets messy.  integers are simpler.

OK.

 > 

Nikita.