The “Project Virtual Reality Check” team just released a new whitepaper: “Hyper-V 2008R2, vSphere 4, XenServer 5.5 on Intel ‘Nehalem’ Xeon 5500“. 

 “If you are looking for an independent advise and a ‘Reality Check’ in relation to Virtualizing Terminal Server and Desktop workloads, if you are curious about the impact of different hypervisors and the performance differences with various hardware and if you are searching for best practices for your virtual Desktops … Project VRC whitepapers are a must read!”

• Highlights, performance differences and best practice conclusions for Terminal Services workloads on:
  • Bare metal Terminal Services; 2003/2008/x86/x64
  • Hypervisors: Citrix  XenServer 5.5, Microsoft Windows Server 2008R2 ‘Hyper-V’ and VMware vSphere 4.0
  • Performance impact using different HP Proliant state-of-the-art hardware using Intel Xeon ‘Nehalem’ x5500  Read the rest of this entry »

In the past I’ve published two articles (here and here) about best practices on running Citrix XenApp (presentation server) on VMware ESX. It were all best practices gathered by other people, but I agreed with a lot of the recommendations. Until recently, I did also agree on using 1 vCPU XenApp virtual machines (with less users per VM) rather than 2 vCPU XenApp virtual machines (with more users per VM). From my own experience and what I got from the community, the performance will be degraded if you use 2 vCPUs. As a mather of fact, during a session on this subject at VMworld 2008 in Las Vegas, this was what stated:

- Always set up your Citrix VMs with 1 vCPU
- Due to the scheduling done by VMware at the hypervisor layer you will degrade performance if you use 2 vCPUs

So having experienced it myself and read about it on the internet, there was no reason for me to try it differently on newer version of ESX. But after reading “VMware Platform Performance Index”, a benchmark performed by the guys over at Virtual Reality Check (Ruben Spruijt and Jeroen van de Kamp), I got confused. Read the rest of this entry »