I have been operating under the mis-conception that "hyperthreaded core sharing" option for VM's running on AMD was irrelevant.
Recently, I changed hyperthreaded core sharing to "none" on a HP/Left Hand VSA and a VoIP VM and realized dramatic performance improvements on both.
Conclusions: under high VM load, hyperthreaded core sharing probably does not matter too much, but at idle/low utilization higher CPU Wait values for a VM can negatively impact performance.
The image below is before/after changing hyperthreaded core sharing to none (you can see after)!
