Re: [PATCH 3/3] mm,vmscan: Reclaim order-0 and compact instead of lumpy reclaim when under light pressure

[KOSAKI Motohiro]

> On Thu, Nov 11, 2010 at 07:07:04PM +0000, Mel Gorman wrote:
> > +	if (COMPACTION_BUILD)
> > +		sc->lumpy_reclaim_mode = LUMPY_MODE_COMPACTION;
> > +	else
> > +		sc->lumpy_reclaim_mode = LUMPY_MODE_CONTIGRECLAIM;
> >  
> 
> Gack, I posted the slightly wrong version. This version prevents lumpy
> reclaim ever being used. The figures I posted were for a patch where
> this condition looked like
> 
>         if (COMPACTION_BUILD && priority > DEF_PRIORITY - 2)
>                 sc->lumpy_reclaim_mode = LUMPY_MODE_COMPACTION;
>         else
>                 sc->lumpy_reclaim_mode = LUMPY_MODE_CONTIGRECLAIM;

Can you please tell us your opinition which is better 1) automatically turn lumby on
by priority (this approach) 2) introduce GFP_LUMPY (andrea proposed). I'm not
sure which is better, then I'd like to hear both pros/cons concern.

Thanks.


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/