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Virtual Testing - Xen Vs. KVM

Some of you might know that I use virtualization for quite some time already, usually to test other OSs and the development of EasyLFS without having to leave my working-environment, and without having to have a free partition.
On my PC I use KVM, as the AMD64 X2 in that box has support for hardware-virtualization, on the notebook I use QEmu together with KQEmu, as the Intel Core Duo lacks that support. So, more or less I'm working in the same environment, except that on my PC I get better performance thanks to the virualization-support in the CPU.
Since both of those solutions use full virtualization the whole hardware is emulated, which cuts down the performance.

Fedora, and probably many current distros include packages for Xen in their repositories. So I thought it might be a good idea to try out a new way to virtualize systems. Xen supports full virtualization and para-virtualization. I'm actually only interested in the para-virtualization part.
The disadvantage here is that the guest-OS has to be modified for this, so it's not possible to just run any OS as it is with KVM or QEmu. But since for Linux everything is available that should be no problem.
Since version 3 Xen also can utilize virtualization-support of the CPU, so that you should get the same CPU-power KVM offers, but better IO-performance since the other parts are used through special drivers.

My first test looks quite promising. I now have an Fedora 8 64-Bit on my PC, Fedora 8 64-Bit in Xen, and Fedora 9 Alpha 64-Bit in KVM. The feeling of the system in Xen is really good. In KVM it's usable, but it doesn't run really smooth. I still have to check the boot-times, also have to compare them with the host-system's boot-time, but I think also here Xen should be the winner.
Also other tests are still to be done. But I think for that I will also re-install Fedora 8 in KVM. I want the two virtual systems to be more or less the same. Fully updated default-installations of Fedora 8 64-Bit, no KDE, with a few tools that I use to compare the performance.
Things I have in mind include rendering with Blender, working in OpenOffice, photo-editing in Gimp, working with InkScape, and some other stuff.

A big advantage of Xen is that you don't need to play around with IPTables. Xen offers bridged networking, with that the virtualized system is actually on your local network. Yes, that system gets it's IP from my router, just as my real box. With KVM/QEmu I have to set-up IP-forwarding and masquerading. Not a big deal, but still something I need to take care of.
The disadvantages I currently see in Xen is that the guest has to be modified for para-virtualization, that disqualifies Xen for Windows and other closed systems. Also, but this might be related to me being new to Xen, it seems that I can only install from the net, but not from a CD, which so far disabled me from installing anything but Fedora.

Well, I'll keep you posted on how my tests are going. So far Xen really looks promising, but I really have to find a way to install other systems than only Fedora in it.
Maybe I'll even make a "xenned" version of EasyLFS. ;-)


I just had my first


I just had my first successful run with virtualization yesterday (Linpus Linux on VirtualBox). I will be paying more attention to this area. It really is convenient to work with different distros this way, though I still see myself dealing with partitions and such for various reasons (but I may change my view as I gain experience with virtualization).

Offtopic, Linpus is interesting as a potential distro for newbies. It would be nice to see a version of LFS embrace a desktop shell that was of similar nature.

LT news link: (I reviewed it in the comments. Not a great review by any means but you can get a sample of Linpus)

Torrent: This is my first time seeding a torrent.. it seems like one person (from poland) is already taking advantage.. hope it works. Also, see if you can wait some hours before attempting the torrent since right now I am the only one seeding it. The person downloading from me now, as is, does not have a very awesome download speed. Then again, anyone interested in remaining on to seed for others later is more than very welcomed to leech Smiling

First of all, I am


First of all, I am interested in getting replies from anyone that gets the download from this torrent and has the iso file work because I have not done this before and I want to make sure the file made it out in tact (yes, I both verified the initial md5 and got the iso working, so any issues would probably be in executing the torrent).

Second, I forgot. If you download from the torrent now, you will also grab pieces from any other peers. Currently, there is only one other peer, but that person already has about 100MB (as off my posting time). I guess this means that if one other person joined in now, that person would tap completely into that peer's upload bandwidth (which if like mine, is much lower than the download bandwidth). But if more than one person joins now, then you will all have to share among my and that existing peer's upload bandwidth (and for all I know, that person may have very very little). Of course, over time all rates would increase as you could all leech off each other. Anyway, I am not sure. It all might work out.

In fact, the rates might go up *very* quickly. Disregard my worries since I think they are unfounded (I was worried about too many people dropping in at the same *exact* time).

Welcome. Welcome all *now*. ..even if you don't intend to stay on after the complete download.

I am using KTorrent by the way. I don't have a lot of experience, but I can probably help out anyone that is new to bittorrent sharing.

Oh, yes. I am also interested to get opinions about Linpus and to know if anyone has had success finding links to package/sources for that distro (won't be as good as the LFS info though which is really what I want).

LinuxTracker looks quite


LinuxTracker looks quite interesting. I might have a look into it and maybe try sharing EasyLFS through it.

Virtualization really is a nice toy. As said, I use it for quite some time already and love the possibility to run another OS or distro just in a window, while still being able to do everything I like.
It's also interesting as a web-developer, as I can just fire up Windows in a window and then test the website in Internet Explorer, without having to reboot my machine.

Did some.


I used to do some Windows XP virtualizing myself in the past. QEMU+KVM modules worked fine. Ran smoothly under debian testing. Never did much but benchmarking. (Actually, I think I used it for teamspeak and skype for a little since the 32-bit binaries didn't work on my 64-bit system.)

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