VMware ESX Server 3.0.1 vs Xen 3.0.3 performance comparison

VMware released a new 22-pages whitepaper called A Performace Comparison of Hypervisors where ESX Server 3.0.1 is compared with Xen 3.0.3 in running Windows virtual machines.

In this case it’s not just a product comparison report. Here different virtualization techniques are put side by side: binary translation for ESX, para-virtualization for Xen:

This paper provides a quantitative and qualitative comparison of two virtualization hypervisors available for the x86 architecture — VMware ESX Server 3.0.1 and open-source Xen 3.0.3 — to validate their readiness for enterprise datacenters. A series of performance experiments was conducted on the latest shipping versions (at the time of this study in November 2006) for both hypervisors using Microsoft Windows as the guest operating system. This white paper discusses the results of these experiments. The discussion in this white paper should help both IT decision makers and end users to choose the right virtualization hypervisor for their datacenters.

The experimental results show that VMware ESX Server delivers the superior, production-ready performance and scalability needed to implement an efficient and responsive datacenter. Furthermore, while we had no problems exercising enterprise virtualization capabilities such as Virtual SMP and virtual machine scalability using the VMware ESX Server hypervisor, we were not successful in running similar tests with the Xen 3.0.3 hypervisor due to product failures.

The system used to run all benchmark tests was an IBM X3500 server with two VT-enabled dual-core 3GHz Intel Woodcrest CPUs (total four cores). Although the test system had 5GB of RAM installed, it was booted with only 1GB of RAM for native tests. Additionally, the test system was configured with a dualport 1Gbps Ethernet adapter and two 146GB SAS disk drives. For native operating system tests, all data was captured using Windows Server 2003 Enterprise Edition R2 32-bit…

While the document is surely interesting, it’s worth to note that:

  • benchmarks have not been conducted following that criteria VMware itself is trying to push with its VMmark
  • Xen development team, XenSource or Virtual Iron (or anybody else) are prevented to release a similar paper to answer back without explicit VMware permission, to not break their EULA. Which is like saying they have to agree the VMware benchmarking approach to play the game.

Read the whitepaper at source.