Web server benchmark: complex, dynamic page created with PHP and MySQL
For this benchmark, I used a default Joomla installation (complete of example pages).
Here are the data:
Wow, these results are very low... It is possible that Apache and PHP on Windows are a not so great choice, but we want to concentrate our attention to the virtualizers results. KVM is finally on top, with VirtualBox very near; then we have Xen and, in the last place, VMware. As Xen is quite good now, does this benchmark contradict the previous Apache static benchmark? No. This time, Apache is capable of spawning only 3 or 4 thread each second. At this rate, Xen has no great problems with threading.
Now, let see CPU load:
We have 100% CPU load for each contender.
All in all, the disk utilization is quite low, but VMware is the loser here. VirtualBox and KVM are the winner, outclassing by a small margin Xen.
UPDATE: a recent article comparing KVM vs VirtualBox can be found here: http://www.ilsistemista.net/index.php/virtualization/12-kvm-vs-virtualbox-40-on-rhel-6.html