Re: Back to the future.

Nigel Cunningham
2007-04-27T21:39:46Z

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Hi.

On Fri, 2007-04-27 at 16:55 +0200, Pavel Machek wrote:
> On Fri 2007-04-27 08:41:56, Pekka Enberg wrote:
> > On 4/27/07, Pavel Machek <pavel@ucw.cz> wrote:
> > >Now, it would be _very_ nice to be able to snapshot system and
> > >continue running, but I just don't see how to do it without extensive
> > >filesystem support.
> >
> > So what kind of support do we need from the filesystem?
>
> "forcedremount ro, not telling anyone, not killing processes" would do
> the trick. FS snapshots might do.

It sounds to me more like Pekka is thinking of checkpointing support. If
that's the case, then remounting filesystems isn't going to be an
option. You want to freeze them for just long enough so that you can
determine what needs saving in the checkpoint. You certainly don't want
to make rw file handles ro and so on.

Nigel

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