Re: [Qemu-devel] [PATCH v4 4/6] introduce new vma archive format

[Dietmar Maurer]

> > For now I have no plans to backup such large VMs.
> 
> 640k ought to be enough for anybody?
> 
> Code is easy enough to change that "works for now" can be good enough.
> Changing file formats and external interfaces is hard, though, so better get 
> it
> right the first time. I don't want to get patches for a new format in a year 
> or two
> just because 128T was enough for the first few users.

OK, will try to remove those limits.

> > > Hint - look at how the qcow2 file format is specified.  You need a
> > > lot more details - enough that someone could independently implement
> > > a program to read and create vma images that would be compatible
> > > with what your implementation produces.
> >
> > The format is really simple, you have the definitions in the header
> > file, and a reference implementation. I am quite sure any experienced
> > developer can write an implementation in a few hours.
> >
> > We do not talk about an extremely complex format like 'qcow2' here.
> 
> This is not an excuse for lacking details in the spec. Quite the opposite. If
> someone has to look at your code in order to implement the format, you have
> failed as a spec writer.

I do not agree here. Clean source code is as good as a spec.