[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Xen-devel] Re: Domain Groups - VMM Support

On Jan 31, 2008, at 3:04 PM, Mike D. Day wrote:
I looked at creating a new hypervisor for scheduling groups, but found
it much simpler to add a new sub-function under the dom_ctl
hypercall. It markedly reduced the size of the patch and I didn't see
any downside. It might make sense to do the same thing here. That way
you wouldn't need to add the new hypercall to every jump table.

I have no objection to making domgrpctl become a set of sub-ops to the existing domain management hypercall. In fact, with the predecessor to domctl (dom0_op) that's how it was implemented. During the domctl developmental churn I separated them to make my life easier, but now it's just an artifact.

To merge with scheduling groups, it may be nice to have an extensible structure like we do with schedulers in Xen.

I agree. There's more to groups than what the two of us have released thus far and adding new features should be made as painless as possible. My suggestion is to save this type of overhaul until we settle on an agreeable functionality merge.

I think its worth an attempt to merge the scheduling groups with
domain groups. I'll start looking at some of the ideas I mentioned
above, be happy to work with anyone else who wants to have a go.

I'm also having a go at the merge and will release a patch set RFC hopefully well before leaving on travel at the end of next week.

With regard to the merge, I've got a question for you. In schedgrps, when a domain joins a group the assumption is that credits are thereafter shared among group members (for as long as it's a member). I think there are cases where it makes sense to group domains without implicitly sharing credits (the null-group in domgrps is such a case). So, I'd like to make it optional for members to delegate their VCPUs to the group. The question is, do you have an opinion whether domains should have to opt-in or opt-out of sharing their credits when joining a group?


Xen-devel mailing list



Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.