Re: [Qemu-devel] [PATCH] migration: adding migration to/from a file

[Uri Lublin]

Paul Brook wrote:
> On Monday 19 January 2009, Uri Lublin wrote:
> > Migration to file, reuses migration-to-fd.
> > Migration from file, uses qemu-fopen directly.
> >
> > The saved state-file should be used only once and removed (or used
> > with -snapshot, or a the disk-image should be copied), as the
> > disk image is not saved, only the VM state.
> >
> > Also there is not point of doing a _live_ migration to file (except
> > for debugging migration code), so I recommend to stop the VM before
> > migrating its state to a file.
> >
> > An advantage migration-to-file over savevm/loadvm is that for the latter
> > a qcow2 is a requirement, while the former works for any image-format.
>
> Wouldn't it be better to just implement savevm to file?
>
> Paul

It sure is simpler.

The possible advantage of migration-to-file (over savevm-to-file) is that in the 
future we may want to implement vm-snapshoting (live save to file + snapshot 
disk-image).

I've implemented a savevm_file, and will send it in a separate email.

Thanks,
   Uri.