[libvirt] RFC: add <currentVcpu> element

[Daniel Veillard]

On Fri, Sep 24, 2010 at 02:25:30PM -0600, Eric Blake wrote:
> On 09/23/2010 04:38 PM, Eric Blake wrote:
> >
> >At the library API layer, I plan on adding:
> >
> >virDomainSetMaxVcpus - alter the <vcpu> xml aspect of a domain for next
> >boot; only affects persistent state
> 
> As I start to code this, it seems a bit redundant.  I can avoid
> virDomainSetMaxVcpus by
> >
> >virDomainSetVcpusFlags - alter the <currentVcpu> xml aspect of a domain,
> >with a flag to state whether the change is persistent (inactive domains
> >or affecting next boot of active domain) or live (active domains only).
> 
> using these flags:
> 
> VIR_SET_VCPU_MAXIMUM = 1
> VIR_SET_VCPU_PERSISTENT = 2
> 
> such that
> 
> virDomainSetVcpusFlags(dom,1,0) - same as existing virDomainSetVcpus
> virDomainSetVcpusFlags(dom,1,VIR_SET_VCPU_MAXIMUM) - error; can't
> change max on active domain
> virDomainSetVcpusFlags(dom,1,VIR_SET_VCPU_MAXIMUM|VIR_SET_VCPU_PERSISTENT)
> - sets <vcpu> xml element for next boot
> virDomainSetVcpusFlags(dom,1,VIR_SET_VCPU_PERSISTENT) - sets
> <currentVcpu> xml element for next boot
> 

  Yes I suggest to get 2 functions one for set and one for get
allowing to do the full set of operations with the use of flags.

  Another question I had, is there a way in QEmu to specifiy a different
cpu count from the -smp indicating the startup count ?

Daniel

-- 
Daniel Veillard      | libxml Gnome XML XSLT toolkit  http://xmlsoft.org/
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