[Libvir] Re: [PATCH] Python bindings now generate exceptions for libvirt errors (third version)

[Daniel Veillard]

On Wed, Mar 28, 2007 at 04:20:18PM +0100, Daniel P. Berrange wrote:
> On Wed, Mar 28, 2007 at 11:10:38AM -0400, Daniel Veillard wrote:
> >   I was thinking about the upcoming remote support, and an RPC is expensive
> > for this kind of informations IMHO.
> 
> The only way to avoid that overhead then would be to add an extra bit of
> info to the virDomainPtr struct, which is populated at the time the virDomainPtr
> object is allocated, so we can avoid calling back into the driver model.

  Seems to me domain->flags bit DOMAIN_IS_DEFINED is the right place.

> That would raise some troublesome cache invalidation issues on the client
> end, though I guess we've already got that issue with the ID value.

  That could be refreshed each time
    virConnectListDefinedDomains()
    virDomainUndefine()
    virNodeGetInfo()
    virDomainCreate()
is called.
The exact same issue could be pointed out for DefinedNetworks, except I
would not expect the cost to really be an issue I would guess it's called
far less frequently, but I'm just guessing.

Daniel

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