THE OFFICIAL BLOG OF THE SBS DIVA

Viorel  in the comments says..."So what about NUMA settings Susan? And Processor core allocation? There is a good opportunity to use Hyper-V Server 8 (2012) for better performance ( >4 core) and NUMA management.

For management purpose I suggest to use add-in (cheap) netcard - onboard cards are server grade and can be more usefull for VM. "

Keep in mind that my personal experience with virtualization... I am talking about one server with two, maybe three, maybe four virtual machines on it.  And I don't think that  NUMA settings really make a huge difference for this size of deployments.  If you guys have tests and benchmarks on small servers,  by all means post them, but most of the NUMA articles I see are server farm discussions and I've not see benchmarks and tests for small servers. 

http://technet.microsoft.com/en-us/magazine/hh750394.aspx

http://blogs.technet.com/b/winserverperformance/archive/2009/12/10/numa-node-balancing.aspx

I think the better idea is to have a good enough machine that you aren't having to squeeze out that last bit of performance. 

For a SBS standard, you give it all cores that are exposed in the virtual interface.  For any other computer, I have personally found that when I put in a small virtual workstation, it worked better with two cpus than one.  Again, think about what cpu you'd be physically buying for the workload.  In the servers that I have running HyperV, the CPU load honestly isn't pulling that much.

I wouldn't recommend HyperV Server 2012 on a client machine.  It's a beta.  Play with it, learn about it, but it's still a work in progress at this time.

http://www.vadapt.com/2011/05/performance-recommendations-for-virtualizing-anything-with-vmware-vsphere-4/

And I'm not a fan of overcommitting ram or resources.  Again, these servers that I'm talking about are typically in a single firm, not in a server farm.  I think if you go down the path of squeezing every last performance out of a server, I think that's asking for trouble in small businesses.  You want room for growth and expansion.

So bottom line I let the box handle the NUMA settings and don't mess with tweaking. 

http://blogs.technet.com/b/windowsserver/archive/2012/04/05/windows-server-8-beta-hyper-v-amp-scale-up-virtual-machines-part-1.aspx

http://www.techrepublic.com/blog/five-apps/five-tips-for-optimizing-hyper-v/726

http://workinghardinit.wordpress.com/2011/08/08/virtualization-with-hyper-v-the-numa-tax-is-not-just-about-dynamic-memory/

Granted you have to understand my HyperV mindset.  In my HyperV world, it's the SBS that is the head cheese and everyone else is secondary.  If you have a SQL server that you want to tweak because there's some app that is written poorly and needs some TLC, well you might want to play around with those settings.

Bottom line I can't give best practices here because I personally haven't done enough testing to know what a best practice for SBS would be.

This one I think you'll have to do some tests yourself.