Re: [Libvir] [PATCH] Xen: Support cpu_weight and cpu_cap for Xen.

> >> I set the information of cpu_weight/cpu_cap to configuration file or > >> sxp format, and execute "virsh start". > >> But the information of weight/cap is lost. > >> libvirt doesn't support cpu_weight and cpu_cap for XML format. > > Right. To me cpu_weight and cpu_cap are tuning informations > they are completely dependant: > - on the hypervisor used (only Xen) > - on a specific scheduler for said hypervisor > - on the runtime operations conditions, i.e. you may want to > revise those settings if you migrate the domain, or change > anything on the target host > > So you are suggesting to add this to the XML, while for me this makes little > sense because of all this specificity. > I have no doubt the patch would 'work' for you, but anybody using a different > hypervisor, or different scheduler, or even someone trying to understand what > those fields are would have no use or informations (your patch does not provide > documentation for the meaning of those attributes). > > I have a problem with extending the XML in a way which makes sense > only for one hypervisor, when using a specific scheduler, and without > a proper definition for what the extension actually means.

> Also Those informations are highly runtime dependant, it's tuning, > it is not critical at all to get that tuning to get the domain up and > running, and once it is running you can actually use the libvirt API > to make the scheduler tuning. > > Can you explain why you absolutely want to have that tuning information > in the XML itself ?