KVM on IBM POWER (PPC64) support in vdsm and ovirt

[Itamar Heim]

On 09/09/2012 07:38 PM, Pradipta Kumar Banerjee wrote:
> Dear All,
> Request your comments and suggestions on managing KVM on IBM POWER (PPC64) via
> ovirt/vdsm
>
> Please find the feature page here -
> http://wiki.ovirt.org/wiki/Features/Vdsm_for_PPC64
>
> The vdsm changes are under discussion and can be found here
> http://gerrit.ovirt.org/7072
>

was in my queue for a while, finally got to it.
thanks for the feature page.
some comments on the text i copy/pasted from the wiki:

> Managing KVM on IBM POWER processors requires changes to both vdsm and ovirt-engine. However the intent is to keep ovirt-engine changes to the minimum
>
> Following are the key changes that will be required
>
>     Enhancing the bootstrapping mechanism in VDSM to handle IBM POWER processor and ppc64 specifics (like cpuid, cpu speed, cpu flags)
>     Adding a new CPU type (IBM POWER) to ovirt-engine

so would this be something like intel/amd/ppc7 type of a thing?
the current cpu types are indeed separated into intel and amd, but this 
only affects the cpu level compatibility feature at the cluster level.
but they are both x86_64, so all other aspects of hardware are the same 
for them.
i think you need a new 'arch' parameter for cluster.
then you need the config to be both version and arch dependent, so you 
could specify things like disk/network/display/audio drives available 
per version, per arch.
now i'm not sure i would call this 'arch', since it would make the 
change to the config too specific, but maybe a more general 'filter' 
column which allows to specify various filters on the config (arch would 
be one of them.
maybe make filter notation a convention of "arch:x86_64" to specify what 
the filter is about.

>     Enhancing the VM templates based on guest device models (disk, network, video) supported by KVM on IBM POWER
>
> KVM on IBM POWER supports the following device models for guest
>
>     virt-io, spapr-vscsi for disk
>     virt-io, e1000, rtl and spapr-vlan for network
>     vga device is supported for guest video
>     Only VNC backend is supported for guest console access.
>
> There is currently no support for SPICE protocol and USB support in guests.
>
> Both NFS and SAN storage is supported for the hosts. iSCSI support is currently work in progress
> User Interface
>
> No new user interfaces are required to be added. However few of the existing interfaces needs to be updated to reflect KVM on IBM POWER related specifics.

i think the arch field is needed at cluster, level, but that's indeed a 
small ui change.
but you probably also need to add the arch to the VM/template entities, 
and to the OVF.
all places using configs (that are relevant) would need to be fixed to 
use the filter.
logic of moving VMs between clusters, creation of VMs from template, 
import/export, etc. would need to validate arch as well.

>
> At the minimum following user interfaces will be affected
>
>     New Server/New Desktop Virtual Machine in userportal
>     New Server/New Desktop Virtual Machine in webadmin
>     Make Template in userportal and webadmin
>     Editing Virtual Disks and Editing Network Interfaces in webadmin
>     New Cluster in webadmin

so actually, these would be affected in having more options, but these 
options would come from enum's.
only change to look and feel of them would probably be the arch field 
(derived from template/cluster, not something user should be able to 
set, just view?)
logic changes would be based on the filtering of relevant values as 
mentioned above.

thanks,
    Itamar