Would like to start a discussion to whats important for virtualiztion, should it be the number of cores on CPU or the CPU speed. what CPU Presently in market is best suited for a test environment AMD Phenom 6 core or a intel i5 quadcore
As far as processing itself goes, I believe that core count matters more than individual core speed. More cores equates to more VM density from a pure ratio perspective. We've been using 6 core Intel processors in our new vSphere hosts at work and they've worked extremely well (5600 series processors).
Absolutely! Workload means much more than pretty much anything when it comes to comfiguring a virtual machine. You don't want to under spec a virtual machine, but you don't want to waste resources, either. That said, CPU performance is generally the last resource to be fully consumed in a virtual environment - RAM and disk will get eaten up first.
In a traditional server virtualization scenario, RAM will generally be the first resource to be exhausted. However, in VDI, keep a sharp eye on storage system performance as this is the first metric that is likely to get out of line because of the way that users interact with desktop PCs.