A. The new four-core Intel Core i7 processor enables hyper-threading, which splits each processor core into two virtual cores to (potentially) improve performance.
The concern with Hyper-V and hyper-threading is that you assign a number of processor cores to each virtual machine (VM). Imagine that you assign one processor each to two guest VMs from the Hyper-V management console, thinking that each is going to use a separate core. What if the hypervisor assigns each of the VMs to the same physical core, with each getting a virtual core? You'd potentially get lousy performance and three physical cores not doing much, where you'd have liked each VM to get its own physical core.
Fortunately, this isn't the case. Microsoft has done a lot of work around Hyper-Threading and Hyper-V. Essentially, while Hyper-Threading will aid performance sometimes, it will never hurt performance, so Hyper-Threading should be enabled.
Related Reading:- Q. Is it true that Hyper-V Server 2008 R2 will support clustering and live migration?
- The Perils of Hyperthreading on SQL Server
- Q. How can I add virtual machines (VMs) to the Hyper-V console?
- Q. What are the correct terms for Hyper-V servers and virtual machines (VMs)?
Check out hundreds more useful Q&As like this in John Savill's FAQ for Windows. Also, watch instructional videos made by John at ITTV.net.
