On (10/07/07 13:04), Peter Zijlstra didst pronounce: > On Tue, 2007-07-10 at 11:20 +0100, Mel Gorman wrote: > > <snip> > > > > lumpy-reclaim-v4.patch > > > > This patch is really what lumpy reclaim is. I believe Peter has looked > > at this and was happy enough at the time although he is cc'd here again > > in case this has changed. This is mainly useful with either grouping > > pages by mobility or the ZONE_MOVABLE stuff. However, at the time the > > patch was proposed, there was a feeling that it might help jumbo frame > > allocation on e1000's and maybe if fsblock optimistically uses > > contiguous pages it would have an application. I would like to see it go > > through to see does it help e1000 at least. > > I'm not seeing how this will help e1000 (and other jumbo drivers). They > typically allocate using GFP_ATOMIC, so in order to satisfy those you'd > need to either have a higher order watermark or do atomic defrag of the > free space. >
It does help somewhat indirectly and in an unsatisfactory manner. When the higher watermarks are breached, the atomic allocation will still succeeed but kswapd will be poked to reclaim at a given order. This is similar to the problems SLUB hits when it uses high-orders frequently. -- Mel Gorman Part-time Phd Student Linux Technology Center University of Limerick IBM Dublin Software Lab - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
