openstack team mailing list archive

[Lorin Hochstein <lorin@xxxxxxx>]

On Dec 4, 2011, at 7:46 AM, Soren Hansen wrote:

> 2011/12/4 Lorin Hochstein <lorin@xxxxxxx>:
>> Some of the LXC-related issues we've run into:
>> 
>> - The CPU affinity issue on LXC you mention. Running LXC with OpenStack, you
>> don't get proper "space sharing" out of the box, each instance actually sees
>> all of the available CPUs. It's possible to restrict this, but that
>> functionality doesn't seem to be exposed through libvirt, so it would have
>> to be implemented in nova.
> 
>> - LXC doesn't currently support volume attachment through libvirt. We were
>> able to implement a workaround by invoking "lxc-attach" inside of OpenStack
>> instead  (e.g., see
>> <https://github.com/usc-isi/nova/blob/hpc-testing/nova/virt/libvirt/connection.py#L482>.
>> But to be able to use lxc-attach, we had to upgrade the Linux kernel in
>> RHEL6.1 from 2.6.32 to 2.6.38. This kernel isn't supported by SGI, which
>> means that we aren't able to load the SGI numa-related kernel modules.
> 
> Why not address these couple of issues in libvirt itself?


I agree that adding support for this stuff within libvirt would be a better way to do it than coding around it in OpenStack. In our case, it was quicker to get something up and running this way than to add the functionality to libvirt.

Lorin
--
Lorin Hochstein, Computer Scientist
USC Information Sciences Institute
703.812.3710
http://www.east.isi.edu/~lorin