[ovirt-devel] Feature review: Cluster parameters override

[Itamar Heim]

On 12/18/2014 06:35 PM, Sven Kieske wrote:
>
>
> On 18/12/14 13:16, Itamar Heim wrote:
>> 3.5 cluster uses -m rhel6.5 for either rhel 6 or rhel 7 host.
>> this is about using a -m rhel7.0 mode
>
> Thanks for the clarification.
>
> What would be the difference inside the vm?
> Different emulated hardware?
> Other setting?
>
> Where can I look up the machine levels and their specific
> meaning (any link to a doc)?
>

I don't know there is a doc covering this other than the code.
it usually covers various tweaks like "oh, this flag should be enabled 
for this cpu type", which can't be done without breaking compatibility 
in a cluster so its fixed only for the next emulation level (i.e., -cpu 
westmere could have more flags with -m rhel66 compared to -m rhel65).

I don't think this is documented too much anywhere, its just a method to 
maintain compatibility (and yes, virtual hardware changes more or less 
as well with that change, again, can't remember a concrete instance)