[Libvir] Proposal for dealing with host devices

[Daniel P. Berrange]

On Wed, Apr 02, 2008 at 05:30:25PM +0100, Richard W.M. Jones wrote:
> The API looks "sane" (modulo my usual concerns about passing random
> XML around, dynamic typing, etc.).
> 
> My only question is: how dynamic are these devices?  Could they be
> listed in the ordinary capabilities XML?  USB devices are of course
> dynamic, but you also talk about caching the output of hald.

My concern with putting it in the capabilities XML, is that there can be
an enourmous number of devices which will result in an XML doc that can
be MBs in size. Aside from being inefficient for apps, I think this would
be unmanagable for admins looking 'virsh capabilities' 

The devices are dynamic, in the sense that they can appear / disappear at
any time - eg USB devices, and their properties can also change at runtime.
This shouldn't be a problem, even if we do cache in libvirt, because HAL
can provide notifications for all these events enablign us to refresh the
cache as needed

Dan.
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