Re: [PATCH v2] mem-hotplug: alloc new page from the next node if zone is MOVABLE_ZONE

From: Andrew Morton
Date: Fri Jul 22 2016 - 16:11:36 EST


On Fri, 22 Jul 2016 10:57:48 +0800 Xishi Qiu <qiuxishi@xxxxxxxxxx> wrote:

> Memory offline could happen on both movable zone and non-movable zone.
> We can offline the whole node if the zone is movable zone, and if the
> zone is non-movable zone, we cannot offline the whole node, because
> some kernel memory can't be migrated.
>
> So if we offline a node with movable zone, use prefer mempolicy to alloc
> new page from the next node instead of the current node or other remote
> nodes, because re-migrate is a waste of time and the distance of the
> remote nodes is often very large.
>
> Also use GFP_HIGHUSER_MOVABLE to alloc new page if the zone is movable
> zone.

This conflicts pretty significantly with your "mem-hotplug: use
different mempolicy in alloc_migrate_target()". Does it replace
"mem-hotplug: use different mempolicy in alloc_migrate_target()" and
your "mem-hotplug: use GFP_HIGHUSER_MOVABLE in,
alloc_migrate_target()", or what?