Re: [PATCH] switch free memory back to MIGRATE_MOVABLE

From: KAMEZAWA Hiroyuki
Date: Sun Jul 12 2009 - 23:00:00 EST


On Mon, 13 Jul 2009 11:47:46 +0900 (JST)
KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx> wrote:

> > When page is back to buddy and its order is bigger than pageblock_order, we can
> > switch its type to MIGRATE_MOVABLE. This can reduce fragmentation. The patch
> > has obvious effect when read a block device and then drop caches.
> >
> > Signed-off-by: Shaohua Li <shaohua.li@xxxxxxxxx>
>
> This patch change hot path, but there is no performance mesurement description.
> Also, I don't like modification buddy core for only drop caches.
>
Li, does this patch imply fallback of migration type doesn't work well ?
What is the bad case ?

-Kame

--
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/