Re: [Qemu-devel] Should we auto-generate IDs?

[Programmingkid]

On Aug 27, 2015, at 9:00 AM, Eric Blake wrote:

> On 08/27/2015 06:32 AM, Jeff Cody wrote:
>> (Added Eric back in to the CC list.  Looks like he got dropped
>> somewhere along the way)
> 
> No thanks to mailman's inept behavior that thinks that it is okay to
> rewrite cc's to drop anyone that doesn't want duplicate email.  But
> don't worry about it; I have my local mail setup to flag any message
> in-reply-to an earlier one where I was in cc, precisely to work around
> mailman stupidly dropping me from cc. [Ideally, I'd filter the duplicate
> messages on my side, and turn off the broken mailman setting
> server-side, but I haven't yet figured out how to get filters working on
> my side that do that correctly.]  I'm hoping that mailman3 is not so
> inept, and that this list archives can migrate to hyperkitty/mailman3 in
> the not-too-distant future.
> 
> 
>> 
>> Do you disagree with the requirements I listed above?  If so, it would
>> be useful to begin the discussion around that.  For ease of
>> discussion, I'll list them again:
>> 
>> * Reserved namespaces
>> * Uniqueness
>> * Non-predictable (to avoid inadvertently creating a de facto ABI)
> 
> Dan made the point that if a name is unpredictable, then we have to
> query to learn what name was assigned.  But if you add two or more
> devices before querying, then you don't know which device has which
> name.  Predictable might actually be better than non-predictable.

Its also more user-friendly.

> Better still might be fixing things to where we add a global command
> line option that outright fails any attempt to create an unnamed object.
> The option would be off by default for back-compat.  But management
> apps like libvirt can turn it on once they are prepared to name every
> object they create (which in turn may imply fixing any remaining
> interfaces that cannot name an object to add in that ability for
> management to pass in a name).  Then there would be no unnamed objects,
> no ambiguity, and no need to generate names.

I do agree with giving every device an ID, but I don't think failing if the user
forgets to give one is necessary. If libvirt doesn't give devices and ID, it
would probably benefit from having QEMU do it for libvirt.