Test iz januara 2010.
Ovo ce biti zanimljivije!
Poredjenje sledecih modela:
VMware Server, version 2.0.2
Xen, version 3.0.3-94
KVM, version 0.83
VirtualBox, version 3.1.2
the virtual machine were created with default settings
MainBoard AsRock P55Pro (Intel P55 chipset + ICH10R)
CPU Intel i860 (2.8 Ghz core speed, 4 x 256 KB L2 cache and 8 MB L3 cache)
# of Cores 4
Memory 8 GB DDR3 @ 1333 Mhz
Disks 4 x 1 TB WD GreenPower disks in RAID10 configuration
Video Nvidia 8400GS w/256 MB DDR2 VRAM
OS 64 bit CentOS 5.4 with kernel version 2.6.18-164.9.el5
Sandra CPU Benchmark
Cache and Memory subsystems
Mixed CPU / Memory performance data
I/O benchmarks: IOMeter
So, who is the winner of the day? Let me repeat: each of the examined virtualizer has its reasons to exist, with its strong points but also with some drawbacks.
However, if I am forced to pick just one of these softwares for a dedicated server machine, I will probably go with VMware: while VirtualBox is quite on par, I think that VMware's paravirtualized network driver give it a slight advantage over the others. Note however that VMware server has some important handicaps: it can manage only 2 snapshots and, as stated above, the WebUI has some problems running on CentOS 5.4. So, if you plan to heavily use the snapshot features, you must use the latest CentOS/RedHat release (5.4) and/or you want a desktop-oriented virtualizer, go with VirtualBox: it has excellent performances and an easy-to-use interface.
If you, instead, love the Linux-standard virtmanager interface, you can go with KVM or Xen. All in all, I would prefer KVM most often that Xen because the latter seems to be very slow in CPU and memory subsystems. Moreover, Xen seems to have some serious problem with massive-multithreaded programs, which is not so good for a server machine.
UPDATE 06/30/2010: the increasing incompatibilities between VMware server 2.0.2 and CentOS 5.4 and later forced us to stop using VMware on our primary virtualization server. Now we're using VirtualBox, coupled with some in-house made scripts to manage the autostart / stop / backup of the virtual machines. So, for a new Linux installation, I would now prefer using VirtualBox vs VMware server.
Ako iko ima bolji benchmark, neka postavi.