Re: [Qemu-devel] [PATCH 1/2] QMP: Introduce commands doc

[Markus Armbruster]

Luiz Capitulino <address@hidden> writes:

> On Thu, 13 May 2010 19:23:11 +0300
> Avi Kivity <address@hidden> wrote:
>
>> On 05/13/2010 06:01 PM, Daniel P. Berrange wrote:
>> >
>> >>   Yes, we do and it's used by libvirt iirc.
>> >>      
>> > This command has been in QEMU for quite a long time now (0.9.x IIRC).
>> >    
>> 
>> It wasn't in QMP until 0.12.  We shouldn't have put it there in that form.
>
>  Your main concern is stability? QMP in 0.12 and current are in preview
> mode, ie. no stability contract until 0.13.

And we absolutely need to make use of that license to improve stuff.
Premature stability leads to stable crap.  Having to get everything
right the first time is just too hard for mortals.

>  We broke it already with a few changes (like capabilities support), so
> anyone using QMP in 0.12 will have to update, although I don't think QMP
> in 0.12 is that useful.
>
>  Having said that, it's been stable for several weeks now and incompatible
> changes have to be coordinated with libvirt.

Yes, we should do our best not to break libvirt, and to help them out
when we have to break it.  That said, QMP is our chance to create a
decent management interface.  We really shouldn't drag in crap from the
human monitor carelessly.

>  So, if you think this is worth the trouble someone could do it.
>
> PS: I remember Anthony saying that he'd put somewhere that QMP is a
>     preview version in 0.12. But I did not find anything, will submit
>     a patch for stable.

I believe 0.12's QMP is too incomplete for serious use, so the risk of
somebody investing big into 0.12's QMP only to get blindsided by 0.13's
should be really low.