Re: Making QEMU easier for management tools and applications

["Daniel P. Berrangé" <berrange@redhat.com>]

On Mon, Jan 27, 2020 at 11:38:49PM +0100, Paolo Bonzini wrote:
> Il lun 27 gen 2020, 21:11 John Snow <jsnow@redhat.com> ha scritto:
> 
> >
> > > ./qemu-core <<EOF
> > {
> >     "machine": "Q35",
> >     "memory": "2GiB",
> >     "accel": "kvm"
> > }
> > EOF
> >
> 
> And now you have to keep all the syntactic sugar that is in vl.c. I don't
> think a redesign of -readconfig should accept anything less verbose than
> 
> - machine:
>     type: q35
>     ram:
>        type: memory-backend-hostmem
>        size: 2G
> - accel:
>   - type: kvm
> 
> And this is not even taking into account disks.
> 
> I like the idea of refactoring all the syntactic sugar into a pre-pass on
> command line options. This is not an entirely new idea, see
> https://www.mail-archive.com/qemu-devel@nongnu.org/msg35024.html.
> 
> I am afraid that this thread is derailing a bit, with lots of pipe dreams
> and no actionable items. How do we get it back in track?

To me the one thing that is clear. No matter what approach we want to
take to QEMU configuration/interaction/CLI/etc, one critical bit of
work is a pre-requisite...

...we must finish[1] the QAPI modelling of QEMU's features in some
short, finite timeframe. We can't let it drag on for another 5 years
or more. I'd say we need a timeframe that is 2 years max, preferrably
1 year.

I don't think we can achieve this by leaving the task up to to the
QAPI maintainers alone. It is unreasonable to put such a burden to
on a small number of people to both implement & review it all. We
need to consider it a project wide priority item so that we can get
broader involvement across all maintainers, in closing the gaps.

I'm not sure if we have any clear list of where our known gaps exist ?

If not a good first action point is do make such a list, so we know
what we're trying to attack.

Regards,
Daniel

[1] For a definition of "finish" that may or may not be equal to
    100% of all possible features. It might be valid to declare
    we only care about "finishing" QAPI for features used by
    libvirt, since those represent the "common case" usage.
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