On Mon, 2007-08-20 at 14:17 -0700, Christoph Lameter wrote:
quoted text
> On Mon, 20 Aug 2007, Peter Zijlstra wrote:
>=20
> > > Its not that different.
> >=20
> > Yes it is, disk based completion does not require memory, network based
> > completion requires unbounded memory.
>=20
> Disk based completion only require no memory if its not on a stack of=20
> other devices and if the interrupt handles is appropriately shaped. If=20
> there are multile levels below or there is some sort of complex=20
> completion handling then this also may require memory.

I'm not aware of such a scenario - but it could well be. Still if it
would it would take a _bounded_ amount of memory per page.

Network would still differ in that it requires an _unbounded_ amount of
packets to receive and process in order to receive that completion.