flobo71 wrote:Yes, LVM and GPLPV were installed as in your guide.
Today, I moved the guest vg to a new Samsung 840 SSD and did the benchmark again.
HD score is now at 4819 with xen! So it was really the difference between SSD and HDD.
Thanks for the update. I didn't notice that your bare metal Windows install was using an SSD, which explains the difference.
Now how is your Xen Passmark result (total) versus the Windows bare metal installation?
EDIT: I just checked some benchmark results regarding regular HDD performance. HDD performance depends a lot on the model, size, and age of the disk, but in any case it is far slower than SSD.
I did some benchmarks on VM disk performance a year ago, comparing SSD, HDDs in stripe mode (LVM, similar to RAID0) and regular LVM formatted disks. Here are the results:
http://forums.linuxmint.com/viewtopic.p ... 40#p702361.
While I cannot compare VM disk performance with bare metal performance of Windows, the graphs shown in the link compare the benchmark results of my Windows VM with benchmark results obtained with other/similar disks running Windows on bare metal. The most telling benchmark result is the last, which shows a Windows VM disk performance result when using LVM disks. One of the disks in the comparison chart is a WD 5000AAKS model, which is one of the disks used in the LVM volume (and probably the one that was used by the benchmark program, as the other disk in the LVM volume is already full). You can see a minor performance penalty when using Xen, where the native (bare metal) performance of the disk is 580 versus 570 points achieved by the Xen Windows VM. Using these figures, Windows VM disk performance under Xen reaches 98% of the performance of a Windows bare metal installation, or 2% disk performance penalty when using Xen (
this result is based on at least 2 assumptions and may be wrong, that is, there may be a bigger performance penalty when using Xen).
Having used the Windows VM to copy several terrabytes of data between different LVM volumes (disks), I didn't see any difference in disk performance between a Windows bare metal installation (or Linux for that matter) and Windows running under Xen. Some time ago Phoronix published benchmarks comparing Xen and KVM performance using an Ubuntu 12.10 guest, but I think those results may be flawed - see
http://www.phoronix.com/forums/showthre ... on-Preview and my comments at posts #18 and #19.
There are a number of benchmarks floating on the web, plus user comments praising one and condemning the other virtualization technology, that I was hoping that this thread here could provide some hard facts, like the Passmark results that allow easy comparison.
I'm sure limitations or flaws can be found with the Passmark benchmarks, but for the purpose of comparing a single Windows VM with Windows bare metal performance in a desktop setup, the Passmark results should be quite indicative.