Slashdot Mirror

← Back to Stories (view on slashdot.org)

Xen 2.0 Virtual Machine Monitor Released

Posted by michael on from the xen-and-the-art-of-system-maintenance dept.

An anonymous reader writes "The Xen team are pleased to announce the release of Xen 2.0, the open-source Virtual Machine Monitor. Xen enables you to run multiple operating systems images concurrently on the same hardware, securely partitioning the resources of the machine between them. Xen uses a technique called 'para-virtualization' to achieve very low performance overhead -- typically just a few percent relative to native. This new release provides kernel support for Linux 2.4.27/2.6.9 and NetBSD, with FreeBSD and Plan9 to follow in the next few weeks. Xen 2.0 runs on almost the entire set of modern x86 hardware supported by Linux, and is easy to 'drop-in' to an existing Linux installation. The new release has a lot more flexibility in how guest OS virtual I/O devices are configured. For example, you can configure arbitrary firewalling, bridging and routing of guest virtual network interfaces, and use copy-on-write LVM volumes or loopback files for storing guest OS disk images. Another new feature is 'live migration', which allows running OS images to be moved between nodes in a cluster without having to stop them. Visit the Xen homepage for downloads and documentation."

21 of 199 comments (clear)

  1. Since we all love screenshots... by Zemplar · · Score: 5, Informative

    Direct link: http://www.cl.cam.ac.uk/Research/SRG/netos/xen/scr eenshots/index.html

  2. Re:64 bit? by Orgazmus · · Score: 3, Informative

    AMD64 is x86-64, and yes it is x86-compatible.
    It should work

    --
    The system had the verbosity of HTML combined with all the readability of compiled assembly viewed as bitmap images
  3. Re:And the point of this application is.. by grub · · Score: 5, Informative


    Let's assume you're an ISP and have a few big machines on the racks. Your customers don't want or need that much horsepower but want their webserver (which you maintain) to run under Linux, or NetBSD, or FreeBSD, or whatever.. You can do it.

    Let's assume you're a developer and want to test your code under various OSs, now you can do it on the same box in realtime (read: no reboots)

    The list goes on and on, it's a great technology.

    --
    Trolling is a art,
  4. Great for free "UX's" but not for Win32 by slashnik · · Score: 5, Informative

    from http://www.cl.cam.ac.uk/Research/SRG/netos/xen/faq .html

    1.3 Which OSes run on Xen?
    To achieve such high performance, Xen requires that OSes are ported to run on it. So far we have stable ports of Linux 2.4, Linux 2.6, and NetBSD. Ports of FreeBSD and Plan 9 are nearing completion.

  5. Re:64 bit? by julesh · · Score: 5, Informative

    From the manual:

    A port specifically for x86/64 is in progress, although Xen already runs on such systems in 32-bit legacy mode

  6. Not as cool. by Anonymous Coward · · Score: 5, Informative

    From the FAQ, it states that you can only run OS's ported to it. While this might be great for cluster testing, or software design, this is defintely no VMware replacement. I am slightly disappointed in this, but I can see where it has its place.

    1. Re:Not as cool. by frenetic3 · · Score: 3, Informative

      No, no... This is HUGE for virtual hosting/virtual private server providers (i.e. web hosting providers that provide you with a virtual machine on which you're root, not some locked down /home directory with a million other people.) VPS'es allow you to run whatever distro you want, be root, run whatever PHP/Python/MySQL versions you need, etc. Basically (IMO) the control and flexibility of a dedicated server without the nightmare of having to replace faulty hardware or dealing with random outages. I have one for the company I run (until it gets too large for a VPS).

      Hosting providers have used UML (and maybe VMware) for this but it's comparatively too slow. Virtuozzo does this (and is successful, and charges a fair amount of $ for it), so they must be shitting bricks right now.

      -fren

      --
      "Where are we going, and why am I in this handbasket?"
  7. Re:MS have one of these by LilMikey · · Score: 3, Informative

    Yes, yes... MS bought out Virtual PC. That was a sad day. There's also VMWare and Virtuozzo if you're looking for any way to "run" 2 OSes at once. I'd have to say that VMWare and VirtualPC are in a class seperate from Xen if for no other reason than performance.

    Xen is designed to run the client operating system as peers. No single vm can steal the whole machine away from the others and the performance overhead of the virtulization is almost nothing as indicated here. No Virtual PC in that graph but in my experience VMWare performs slightly better than Virtual PC and my observations are supported by these guys. VMWare and VirtualPC run the OS as just another processes in the real OS. Something terrible happens to the host OS and the VPC/VM slows to a crawl. Something major happens in the virtual OS and the host slows to a crawl. They're more emulation that virtualization.

    --
    LilMikey.com... I'll stop doing it when you sto
  8. Re:Plan 9....? by Hatta · · Score: 2, Informative

    Plan 9 from outer space??

    Not quite. Plan 9 from Bell Labs.

    --
    Give me Classic Slashdot or give me death!
  9. Re:Alas, no Windows... by petaflop · · Score: 3, Informative

    Which is very interesting, given that that project is sponsered by the EPSRC (Engineering and physical sciences research council) and Microsoft UK. See page 11 of the White paper for details.

  10. Re:Alas, no Windows... by julesh · · Score: 4, Informative

    VMware developers must have bought a license, so what's the problem here?

    VMware runs an unmodified version of Windows by presenting a virtual machine that is practically indistinguishable from a real PC. Therefore they don't need a license.

  11. Re:64 bit? by isolationism · · Score: 2, Informative
    Being an Athlon 64 Socket 939 owner I tried to do just that -- unfortunately it didn't compile cleanly "out of the box" (at least, for me) just yet, it errors out on compiling file_stream.o because of something to do with libxutil.so.

    You could probably compile it fine in a 32-bit chroot or something, but I'll leave that to someone else to try. I'm happy to wait for release 2.x for full AMD64 support.

    Of course, don't let me stop you from trying. Anyone who does get it to compile, let us know what you did ...

  12. Re:It's not enough by RLiegh · · Score: 2, Informative

    For fucks sake! If you're going to pay for Windows 98 you might as well also pay for VMWare.

    On the other hand if you're going to pirate Windows 98 you may as well also pirate VMWare.

    VMware is hundreds, read that again: hundreds of dollars; windows 98....isn't.

    Also, the version which I'm using is an upgrade version I have which came with a used laptop I paid $50 for a couple years back. When it asks for the windows disks I'm upgrading from, I throw in the windows 3.1 disks I've had sitting around since 94.

    As far as vmware goes. vmware will not switch to fullscreen mode because of weirdness with DGA under X which I could not fix even after spending a fair amount of time googling for it; that alone puts it in the not-for-thirty dollars camp, and definately not for hundreds of $$$.

  13. Steal or Deal? by ringe82 · · Score: 2, Informative
    Most people with a little knowledge of history would say so, but I think we've got to realize Microsoft finally seems to know there's a time to steal and a time to deal.
    Work on Xen has been supported by UK EPSRC grant GR/S01894, Intel Research, HP Labs and Microsoft Research.
  14. QEMU by nns6561 · · Score: 4, Informative

    QEMU is a similar open source project. It's supposed to run unmodified versions of Windows even. Does anybody know what QEMU's lastest performance numbers are?

    1. Re:QEMU by dmaxwell · · Score: 2, Informative

      Win98 is barely usable on a 2.4 Ghz PIV. It is good for running proprietary groupware clients and the like. The next version will have decent SB16 support and some small performance increases.

    2. Re:QEMU by Abcd1234 · · Score: 2, Informative

      Actually, it's really that similar at all. Xen is a virtualization architecture that allows you to run "ported" OSs concurrently. QEMU is a full x86 hardware emulator, CPU and all, meaning that the OS thinks it's running on real hardware. VMWare, which is in yet another class, virtualizes the x86 CPU, along with trapping and executing "leaky" instructions (since Intel can't seem to make a real, virtualizable ISA), meaning the majority of the guest software instructions are executed on the underlying CPU, but the rest of the architecture is emulated, just like in QEMU. Note, this requires VMWare to run on real x86 hardware, though, whereas QEMU can run basically anywhere, and Xen could, in theory, run any OS that was ported to the underlying hardware architecture.

    3. Re:QEMU by oldmanmtn · · Score: 2, Informative

      Performance numbers? No. Performance perception: unusably slow.

      I was able to install a recent build of Solaris 10 on it without a hitch, so the functionality seems to be very solid. However, the installation took almost 6 hours, or about 10 times longer than a native installation. Since installation is all about I/O, this doesn't bode well for actually running the OS when the CPU performance will be much more important.

      As for your suggestion that QEMU is similar to Xen: no, it's not. QEMU emulates the entire machine - including the CPU. This leads to the hideous performance I described. Xen doesn't emulate the CPU - the real CPU executes the instructions. I haven't used Xen yet, but this should allow it to run at near-native performance.

      --
      - Old Man of the Mountain ---- "I want to disturb my neighbor"
  15. coLinux (Cooperative Linux) by thefon · · Score: 2, Informative

    I use http://www.colinux.org/ to run linux inside windows 2000/XP. It is free and a lot faster than vmware. You can even download a debian image for a quickstart.

  16. Re:This is a VM platform, not a VMWare competitor by Sir_Ahzz · · Score: 3, Informative

    Or if you wanted to run different distros. Or if you wanted to isolate virtual server kernels from each other since it HAS been known to have a kernel flaw that let a jail/vserver into the other vservers. From a security standpoint, I wouldn't sell virtual servers like vserver. It's just asking to get your ass handed to you by a hacker in my experience. 8-P With xen, even if you get a root comprimise, or a kernel comprimise, the individual domains are isolated from each other in such a way as to prevent one from interfering with another.

    --
    Sig? What sig? OH! THIS Sig. :)
  17. Re:versus UML? by Anonymous Coward · · Score: 1, Informative

    Don't forget Xen does live migration and suspend / resume of virtual machine, which (AFAIK) UML does not.