Re: Back to the future.

Pekka J Enberg
2007-04-27T04:52:14Z

On Thu, 2007-04-26 at 09:56 -0700, Linus Torvalds wrote:
> > which will map in the snapshot, return the mapped address and the size
> > (and if you want to support snapshots > 4GB, be my guest, but I suspect
> > you're actually *better* off just admitting that if you cannot shrink
> > the snapshot to less than 32 bits, it's not worth doing)

On Fri, 27 Apr 2007, Nigel Cunningham wrote:
> That inherently limits the image to half of available ram (you need
> somewhere to store the snapshot), so you won't get the full image you
> express interest in below.

It doesn't. We can make the userspace mapped pages copy-on-write. As long
as the userspace makes sure there's not much activity during
snapshot/shutdown, we will be fine. What we probably do need to copy is
kernel pages.

Pekka