Re: Back to the future.

[David Lang <david.lang@digitalinsight.com>]

On Thu, 26 Apr 2007, Chase Venters wrote:

> On Thu, 26 Apr 2007, Linus Torvalds wrote:
>
>> 
>> Once you have that snapshot image in user space you can do anything you
>> want. And again: you'd hav a fully working system: not any degradation
>> *at*all*. If you're in X, then X will continue running etc even after the
>> snapshotting, although obviously the snapshotting will have tried to page
>> a lot of stuff out in order to make the snapshot smaller, so you'll likely
>> be crawling.
>> 
>
> In fact... If you're just paging out to make a smaller snapshot (ie, not
> to free up memory), couldn't you just swap it out (if it's not backed by a
> file) then mark it as "half-released"... ie, the snapshot writing code
> ignores it knowing that it will be available on disk at resume, but then
> when the snapshot is complete it's still available in physical RAM,
> preventing user-space from crawling due to the necessity of paging it all
> back in?

your swap space may end up being re-used before you restore with std

David Lang