Re: [Qemu-devel] Re: Strategic decision: COW format

[Markus Armbruster]

Aurelien Jarno <address@hidden> writes:

[...]
> I agree that the best would be to have a single format, and it's
> probably a goal to have. That said, what is most important to my view is
> having one or two formats which together have _all_ the features (and 
> here I consider speed as a feature) of the existing qcow2 format. QED or
> FVD have been designed with the "virtualization in a datacenter" in mind,
> and are very good for this use. OTOH they don't support compression or 
> snapshotting, that are quite useful for demo, debugging, testing, or
> even for occasionally running a Windows VM, in other words in situations
> where the speed is not the priority.

Speed not a priority means the requirements are pretty radically
different.  Satisfying two radically different sets of requirements with
the same format could be difficult.  Great to have, but possibly
difficult.

> If we can't find a tradeoff for that, we should go for two instead of 
> one image format.

Less bad than a jack-of-all-trades.