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Red Hat Pledges 'Integrated Virtualization'

OSS_ilation writes "Red Hat was all about virtualization in a recent announcement for an 'integrated virtualization' initiative with XenSource and chipmakers AMD and Intel. The move was seen as a way for Red Hat to bring its commitment to virtualization technology into 'sharper focus [...] with the release of a product roadmap that includes virtualization technology built into its enterprise version of Linux.' Red Hat's CTO, Brian Stevens, said the move would remove the complex 'rocket science' aspect of virtualization, and drive the technology into more enterprises as a result."

91 comments

  1. Virtualization in the kernel. by babbling · · Score: 1, Interesting

    Wasn't virtualization supposed to go into the kernel at some point? I was under the impression it got delayed for some reason. Anyone know the status of it? Is the virtualization in the kernel what Red Hat are going to use to provide this?

  2. Sweet by maelstrom · · Score: 2, Informative

    No matter what the haters say, Red Hat is one of the main distributions I go to when building a new server (CentOS if no support needed). Things like integrated SELinux, easy to use yum (or rpm apt-get), and now virtualization make it very impressive.

    --
    The more you know, the less you understand.
    1. Re:Sweet by 0racle · · Score: 0, Troll

      Except that Virtualization on Linux was almost always as easy as on Windows, unless for some reason you use Xen. If they really wanted to remove the 'rocket-science' aspect from virtualization they would simply strike a deal with a company that has a mature virtualization product. However, that doesn't make Red Hat look like some industry leader in the area as virtualization as saying they're going to take an OSS product and create some group around it.

      Red Hat and Xen - World leader in virtualization as long as you only want to run Linux or BSD.

      --
      "I use a Mac because I'm just better than you are."
    2. Re:Sweet by maelstrom · · Score: 2, Insightful

      What are you even talking about? VMWare? It isn't open source.

      --
      The more you know, the less you understand.
    3. Re:Sweet by gordyf · · Score: 3, Insightful
      Red Hat and Xen - World leader in virtualization as long as you only want to run Linux or BSD.

      According to Wikipedia's Xen article, Xen will work with any OS if you're using a recent AMD or Intel chip with virtualization extensions, so that's not strictly speaking true.

    4. Re:Sweet by Anonymous Coward · · Score: 0
      as long as you only want to run Linux or BSD.

      What else would you be running? Seriously, windows? gtfo!

    5. Re:Sweet by msh104 · · Score: 1

      and above that, vmware does emulation, not virtualisation.

      vmware emulated all hardware so that you can run every os under it. virtualisation means that the host and the client are almost the very same thing and share almost everything. this is much faster then the emulation approach but also more complicated to implement.

      the disadvantage of virtualisation is that the client will have to be modified.

      and surely there is currently no simple way to do that in linux that I am aware of.

    6. Re:Sweet by ettlz · · Score: 1

      Doesn't qemu with kqemu provide [limited] virtualisation (in conjunction with its dynamic code re-writing)?

    7. Re:Sweet by mobby_6kl · · Score: 1

      No, what VMWare does is not emulation. For an example of how emulation works, have a look at Bochs.

    8. Re:Sweet by Mateito · · Score: 1

      > VMWare? It isn't open source.

      That doesn't mean that its not freely available.

    9. Re:Sweet by maelstrom · · Score: 1

      No, but it means it can't be distributed with Red Hat.

      --
      The more you know, the less you understand.
  3. Red Hat leaving the desktop arena? by Anonymous Coward · · Score: 0

    Recently I switched my laptop to Tomahawk Desktop because of its impressive array of features for mobile computing.

    It seems now Red Hat is not focusing much on desktop and laptops. I wonder whether the desktop and laptop arena not lucrative or is there really something else?

    1. Re:Red Hat leaving the desktop arena? by pembo13 · · Score: 1

      I guess you missed a few news bulletings. RedHat has never sold a desktop/laptop product. The offered a free comunity supported version, but a lot of people in the community complained about too much RedHat control. That (and other issues) led to RedHat spinning of their desktop product to a more community driven product, with a different name: Fedora. Some like it, some don't. I personally like it.

      --
      "Thanks for all the money you paid to us. We've used it to buy off ISO among other things" -Microsoft
    2. Re:Red Hat leaving the desktop arena? by drsmithy · · Score: 2, Informative
      RedHat has never sold a desktop/laptop product.

      Yes, they do.

    3. Re:Red Hat leaving the desktop arena? by pembo13 · · Score: 1

      I stand corrected. Still, this doesn't seem like a typical desktop distro.

      --
      "Thanks for all the money you paid to us. We've used it to buy off ISO among other things" -Microsoft
    4. Re:Red Hat leaving the desktop arena? by LnxAddct · · Score: 1

      It's not a typical distro, its designed for business environments.It is not targeted to typical consumers.
      Regards,
      Steve

    5. Re:Red Hat leaving the desktop arena? by kwalker · · Score: 1

      The Red Hat 5.2 and 6.2 CDs and boxes I have at home disagree with you. Beyond that, you're fairly correct.

      --
      ... And so it comes to this.
  4. This sucks by NitsujTPU · · Score: 0, Offtopic

    Either people have actually begun reading the articles thorougly before posting, nobody is interested in technology on this site anymore... opting for politics.

    1. Re:This sucks by AoT · · Score: 3, Insightful

      Probably RTFA, trying to figure out WTF 'Integrated Virtualization' means.

    2. Re:This sucks by NitsujTPU · · Score: 4, Informative

      It can take a couple of forms. In one form, it would be hooks for a VMM requiring a host OS.

      In another form (which I know that Xen supports) it provides ways for the VMM to have control over the host OS, though Xen supposedly supports a number of these methods though ways not requiring modification to the source code.

      There are others too (IE, replicating an image of a running OS, snapshotting the OS).

      The article doesn't really tell you what they mean at all. I've seen all of these discussed in the context of Linux and Xen before. In fact, I thought that most of those were implemented.

    3. Re:This sucks by Anonymous Coward · · Score: 0

      Like it or not, information technology is politics these days.

      Our entire society is built almost completely on IT... and IT is becoming totally controlled by a few companies with monopolies -- be they monopolies on hardware, software or "intellectual property", in which ideas or bits of code are "owned" by on entity. Increasingly we are seeing the companies with these monopolies acting together to create total lockdown -- Trusted Computing -- to ensure that they will have perpetual and total control over the computing infrastructure... by forcing us to trust them with no control over that trust relationship. And they are doing it with very little scrutiny -- and with the tacit support of a media cowed by money and power, and ignorance of the technology. A media who hear the term "DRM" and can only think of music and video file sharing and not the wider issues of DRM, since it really means any kind of digital data (documents, emails anything), and requires total control over software application development (code is what DRM controls, not data) to make it work. On top of that, we are also seeing governments using IT to collect and process vast amounts of data on its citizenry. They know all about us, and we know nothing about them. fundamentally shifting the balance between citizen and state.

      Abuse of laws. Abuse of lobbying. Abuse of power. Believe me... IT is all about politics these days.

    4. Re:This sucks by NitsujTPU · · Score: 1

      That's a weak argument. It's fine to argue that politcs belong on the site (as they relate to technology). It's stupid to argue that nobody on a tech site should be interested in technology anymore, because they've all become politicians.

    5. Re:This sucks by Anonymous Coward · · Score: 0

      That's a weak argument.

      Hardly...

      snip straw man argument

      Only you seem to think that *only* politics is discussed... possibly because you are an idiot.

    6. Re:This sucks by NitsujTPU · · Score: 1

      When people would rather astroturf about how they hate Bush than astroturf about how they hate vi (or emacs if they're vi users), things have gone downhill on a "tech" site, however much I enjoy this place.

  5. yAY! by Pixelmixer · · Score: 0, Flamebait

    maybe this means I can finally toss out the old MS OS... Lack of developement software support is my only reason for staying, despite the gaggins sensation i get everytime i have to boot windows :( haha

    --
    "What happend to just paying for a product without being constantly nibbled to death by Credit Card Ducks?"
    1. Re:yAY! by Cromac · · Score: 1
      maybe this means I can finally toss out the old MS OS.

      You don't seem to understand what virtualization is. It just means emulating hardware, so you'll still be running 'the old MS OS' if you want Windows, you'll just be able to run it without dedicating any hardware to it. Check out VMWare, you can already do it for free today.

    2. Re:yAY! by Pixelmixer · · Score: 1

      eh, maybe i should have added the little /sarcasm at the bottom... didnt mean it to be literal... the post above me said something about how people dont read the article and dont know what virtualization means ;p

      --
      "What happend to just paying for a product without being constantly nibbled to death by Credit Card Ducks?"
    3. Re:yAY! by Anonymous Coward · · Score: 0

      This is misleading.

      Xen should be considered more of a super OS (called a hypervisor), it shares resources between other OSs in the same manner that an OS shares resources between applications.

  6. What is this? by Saeed+al-Sahaf · · Score: 3, Insightful

    I'm sorry, obviously I don't need it, because I don't have a clue what it is. What is this "virtualization"? Linky, please?

    --
    "Who are in control, they are not in control of anything - they don't even control themselves!" - Glen Beck
    1. Re:What is this? by barefootgenius · · Score: 5, Informative
      --
      /. bug #926803 - Why I can post.
    2. Re:What is this? by Anonymous Coward · · Score: 0

      Is this not User Mode Linux? How is it different?

      http://user-mode-linux.sourceforge.net/

    3. Re:What is this? by Anonymous Coward · · Score: 0

      Someone who can't use Google is marked as "Insightful"?

  7. Beta testers == lab rats by grasshoppa · · Score: 0, Flamebait

    Except can hope for death. From TFA:
    "With Fedora Core 5, we will take the rocket science of virtualization away from the end user and get virtualization out-of-the-box experience in their hands," Stevens said.

    Where it will promptly mutate in to a flesh eating form of virus, obliterating you, your family and your dog.

    A word to the wise; Stay away from fedora cores. If you must use one, choose one that's been out for a while. Trust me; You'll be glad you did.

    --
    Mod me down with all of your hatred and your journey towards the dark side will be complete!
    1. Re:Beta testers == lab rats by Anonymous Coward · · Score: 0

      thats fud...

      Fedora Core X releases are stable and functional. I've been using them since day one for various tasks. Even had much of the software previous RH releases (pre-rhel3) that RH finally got around to adding back it at rhel4.

      Now Fedora Core X Test Y, that is different, and is not intended to be stable, it is TEST :P

    2. Re:Beta testers == lab rats by pembo13 · · Score: 1

      Hhmm. You must know something I don't. I have been using Fedora full time on servers, desktops, workstations and laptops (not all at one time) since Fedora Core 2. I currently have FC5Test3 installed on a spare machine. I can handly use Windows anymore since it lacks so man features that I have grown accustom too. (I know this has little to do with Fedora specifically).

      --
      "Thanks for all the money you paid to us. We've used it to buy off ISO among other things" -Microsoft
    3. Re:Beta testers == lab rats by ettlz · · Score: 5, Interesting
      A word to the wise; Stay away from fedora cores. If you must use one, choose one that's been out for a while.

      You sound like a bitter, bitter Slashdotter.

      This "Fedora's a beta testbed for suckers" stuff is utter crap. Fedora is a testbed not for stability, but for cutting edge technologies that may filter down into Enterprise many months later. And from what I hear, FC5 will introduce some exciting new things. The stuff that goes in isn't generally any more unstable or poorly-built that the pristine sources from which it derives, plus you've got the support of the community and the Bugzilla.

      The Fedoras are nice, powerful distributions. Far nicer (and to be honest, I think more polised) than Enterprise. For me, they've got the right balance of modern usability and technical accessibility. Yes, I like cutting edge.

    4. Re:Beta testers == lab rats by mikelieman · · Score: 2, Informative

      I've been using the FC5RC3 on a test system which uses Xen for a wacky combo of MySQL, and PHP that some groupware requires which conflicted with the standard Core packages.

      From what I've seen in going from "Rolling Your Own" to the FC5 distro, is that Fedora got it RIGHT on this one. "It Just Works" for me.

      When the host machine gets rebooted, it doesn't even reboot the Guests. They just get suspended, and resumed when the machine comes back up.

      Two Thumbs Up.

      --
      Technology -- No Place For Wimps! Grateful Dead and Jerry Garcia Chatroom -- http://www.wemissjerry.org
  8. Red Hat + Xen by plasticsquirrel · · Score: 5, Informative

    From what I gathered from the article, it looks like Red Hat is porting their distro to the Xen virtual machines and then packaging that with the natively-compiled OS as a virtual machine manager. It's nice to see a distro pick up Xen officially and package it an easy-to-use way, since Xen has very impressive performance. The article or the summary probably should have included a link to the Xen web site, so if you want to know more: the Xen site.

    --
    Systemd: the PulseAudio of init systems
    1. Re:Red Hat + Xen by NitsujTPU · · Score: 1

      Ahh, that makes more sense. I remember that Xen had natively compiled OS's in order to make use of some of its features.

    2. Re:Red Hat + Xen by cerberusss · · Score: 1
      since Xen has very impressive performance.

      I disagree. Where did you get that information?

      I ran unixbench in a hosted Xen and it took ten times as long as on my workstation at home. So no, I don't think the performance is very impressive. I do think the rest is impressive, though.

      --
      8 of 13 people found this answer helpful. Did you?
    3. Re:Red Hat + Xen by Anonymous Coward · · Score: 0

      Did you recompile libc without TLS, or at least move /lib/tls to /lib/tls.disabled or such? Was it Xen 3.0.1? What kind of performance issues did you have? What kind of storage system was it using?

    4. Re:Red Hat + Xen by cerberusss · · Score: 2, Interesting

      It's a hosted solution; I only have access to the guest OS. The solution is advertised as Xen 3.0.1. I don't know the storage system. I didn't have performance issues; I just ran unixbench and saw that it took a LONG time, see the results here: unix_bench_xen_budgetdedicated.

      --
      8 of 13 people found this answer helpful. Did you?
    5. Re:Red Hat + Xen by raynet · · Score: 2, Insightful

      Sure, but you shouldn't be using Linux at all as it is so slow. I just did a benchmark on my Sun Ultra 1 (143MHz Ultrasparc) running Linux (and there was couple other CPU intensive programs running the backround too, but why should they affect the results) and it was much much slower than the same benchmark on my Windows PC (3GHz P4).

      In any case, do a benchmark with your workstation using Xen and without Xen. Remember to test VMWare or UML too. THEN you can say if Xen is impressive or not...

      --
      - Raynet --> .
    6. Re:Red Hat + Xen by DeathBunny · · Score: 1

      Huh? You ran a benchmark on two different hardware systems and you're using *that* to compare the difference in *software* configuration? Do you really need someone to explain to you why that makes no sense?

    7. Re:Red Hat + Xen by T-Ranger · · Score: 1

      Just the kernel, at least untill the next gen chips from Intel and AMD come out.

    8. Re:Red Hat + Xen by Anonymous Coward · · Score: 0

      SuSE already offers this, from 10.0 at least. (Maybe earlier, but that's when I started using it.)

    9. Re:Red Hat + Xen by AmigaBen · · Score: 1

      Kinda my thoughts.. Sounds like RedHat is trying to play catchup to Novell/Suse.

      --
      +5 Insightful, really!
    10. Re:Red Hat + Xen by cerberusss · · Score: 1

      No need to get pedantic. The difference was 10 times as slow for the hosted Xen. Now I agree that there are loads of assumptions here, but I just wondered where the poster got its information from.

      --
      8 of 13 people found this answer helpful. Did you?
  9. Should be interesting, at least ... by tinkertim · · Score: 4, Insightful

    I'm wondering if they aren't just going to Include Xen, this would explain the sudden push on Xen's part to get a working FC4 installer out the door.

    I'm not the world's biggest RH fan as far as using it, however I do respect that RH basically made Linux the household word that it is.

    The end result, regardless of the politics is going to be web sites and databases remaining available to visitors a larger percent of the time, and end users getting a firmer grasp on how their OS works :) Either way you go this is going to be a good thing.

    For consultants specializing in helping to bring virtualization to the table for their clients, fear not .. people are going to need help with this for years to come. I think it will help us do what we like doing (plan networks) instead of worrying so much about the semantics of getting (x software) installed and working. This means easier work, quicker turnover and more clients.

    My concern is RH distributes (stock) very insecurely. My hope is they also address issues like /dev/shm allowing execution, and other (seemingly) little quirks that allow so much spam to wind its way throughout the internet. They're catching up, it seems with just how people are using their product, hosting web sites (broadly). I hope they also make it safer in the process so that whatever layer they use for virtualization doesn't also get a rep for being insecure.

    I'm not a huge Fedora fan, but I do respect them enough to withold judgement until I see what they put out. I guess you could count me as 'cautious, but anxious' to see it.

    1. Re:Should be interesting, at least ... by Tough+Love · · Score: 1

      I'm not the world's biggest RH fan as far as using it, however I do respect that RH basically made Linux the household word that it is.

      Really? And IBM had nothing to do with it?

      --
      When all you have is a hammer, every problem starts to look like a thumb.
    2. Re:Should be interesting, at least ... by tinkertim · · Score: 1

      Good point (and my bad for the sweeping statement). IBM did have quite a bit to do with it.

      I had an old Think Pad , my first Penguin Laptop. It played a little sound byte when booting (RH7) :

      "I'm Good Enough, and I'm Smart Enough, And Dog Gonnit, People Like Me!"

      On airplanes I used to mouth the words as it played, and it (usually) got me a bit more leg room as the person next to me would generally move after giving me (and my odd looking screen) a strange look.

      But the topic was Red Hat, and moderation has been meyhem lately .. so I didn't want to go too far off topic (like I am now ... ) ;)

  10. Xen in the enterprise by Grumpy+Wombat · · Score: 4, Interesting

    This is great news. I'm currently involved in a rollout of Red Hat Enterprise for a large Govt Department in Western Australia and we have had to make extensive use of VMWare's ESX. Having Xen in RH would streamline our development process and make a Red Hat ES development environment more attractive for large enterprise use.

  11. Currently using Virtuozzon on top of Red Hat by lappy512 · · Score: 1

    I'm currently using Virtuozzo (based on OpenVZ) for my website (in my sig) on top of Red Hat...works great. If Red Hat integrated Xen into their OS, that would be even more convienent for webmasters like me :)

  12. RPM by peterfa · · Score: 0, Flamebait

    I wonder if this virtualization removes the dependency hell from their package manager. This Virtual Integration might mean that you can finally use RPM without all that fuss. Then you could actually integrate your RH machine into a business environment without all the pain.

    1. Re:RPM by pembo13 · · Score: 1

      The last time I ran into RPM hell of any sort was in FC2 I think. In FC4 I have no such problems. Maybe it is because I use yum.

      --
      "Thanks for all the money you paid to us. We've used it to buy off ISO among other things" -Microsoft
    2. Re:RPM by peterfa · · Score: 1

      I used yum, it fails often. If there are like more than 20 dependencies, it chokes to death.

    3. Re:RPM by pembo13 · · Score: 1

      Are you using unofficial repos with yum? If so, this is very far from RedHat's fault. There is zero reason for the fedora repos to give dependancy hell. If this does happen, then there really is a problem.

      --
      "Thanks for all the money you paid to us. We've used it to buy off ISO among other things" -Microsoft
    4. Re:RPM by peterfa · · Score: 1

      Well, I have Gentoo now, so I have a different type of dependency hell.

  13. Xen Vs. Linux VServer by linuxguy · · Score: 5, Informative

    A couple of months ago I was faced with the problem of needing to host multiple domains on one system. I initially considered Xen for my virtual servers need. However when I learned that this solution would not share the memory (each Vserver would have to have its dedicated memory) I decided to try out Linux Vserver. I have been a happy user of Linux Vserver since then.

    With Linux Vserver you only run one kernel on your system where with Xen each virtual server runs its own kernel. This presents some limitations for Linux Vserver. For example the guest virtual servers cannot have the network loopback interface lo. But almost all of these I could live without.

    Now if I want to start adding more virtual servers I can, without having to worry about running out of memory.

    1. Re:Xen Vs. Linux VServer by Anonymous Coward · · Score: 0

      separation of memory areas is (partly) a by-product of xen being a hypervisor. if you were to run some linux, some bsd and - god forbid - some windows as instances in xen, sharing their memory would be pretty pointless (aside from fiendishly difficult if not impossible).

      besides, i'm happy one guest os doesn't see the memory of another guest os. keeps things seperate that don't have anything to do with each other in the first place.

    2. Re:Xen Vs. Linux VServer by NitsujTPU · · Score: 4, Informative

      There is a paper where the authors used Xen in a manner in which they copied the image of the running OS. A copy on write police was implemented, so RAM usage would be minimal. They got Xen to scale to thousands of virtual servers on some form of relatively reasonable hardware.

      It is worth noting, though, that this is part of the point of what Xen is. Xen is a VMM, and part of the point is that you virtualize the machinery so you can run multiple OS's and such. This really is the direction that everything is going. The technologies that you can build on top of this are very... convenient.

    3. Re:Xen Vs. Linux VServer by gtrubetskoy · · Score: 2, Interesting
      With Linux Vserver you only run one kernel on your system where with Xen each virtual server runs its own kernel. This presents some limitations for Linux Vserver. For example the guest virtual servers cannot have the network loopback interface lo. But almost all of these I could live without.

      To me, one kernel is an advantage, not a limitation. A kernel upgrade on a VServer box is a one-step operation, whereas on a Xen (or like) you have to repeat it for every guest.

      Also a great thing about VServer is that the filesystem can be shared between host ang guest. So I can run one backup on the host, which takes care of all the guests.

      Another thing I like is the ability to "enter" a guest from the host by simply switching the context - no need to actually log in.

      And the virtualized loopback and iptables is just a matter of time - the alpha branches of VServer already have it.

      I should also mention that aside from Vserver there is something called OpenVZ, which is the same concept and more features. What turns me off about OpenVZ and Xen is that the community around these projects is commercially sustained, which means that the project evolution will gravitate in a direction that satisfies shareholders and that the project would be greatly impacted by a business failure (which happens quite often these days).

      Vserver on the other hand is a truly indepndent open source community, very much like the communities that drive other most succesful projects out there. I've been following this project for a couple of years now, things may not move as fast, but folks are involved out of the love for technology, and the quality of the software reflects this.

    4. Re:Xen Vs. Linux VServer by styrotech · · Score: 2, Informative

      To me, one kernel is an advantage, not a limitation. A kernel upgrade on a VServer box is a one-step operation, whereas on a Xen (or like) you have to repeat it for every guest.

      Not quite. Unless your guests use different kernels (in which case you wouldn't be using VServer anyway), you only have one guest kernel to worry about. I have a Xen machine running 4 Debian Sarge machines - in the boot directory of the host there is the host kernel and a guest kernel. All guest instances boot off that one guest kernel. There are no kernels installed in the guests themselves.

      Sure upgrading two kernels is more work than upgrading one kernel, but it not as bad as you think.

  14. virtualization by alxkit · · Score: 1

    if someone sais `virtualization` one more time i will virtually throw up. virtually.

  15. Xen traded full OS compatibility... by Anonymous Coward · · Score: 1, Interesting

    On the wiki xen site it says,"Xen trades full OS binary compatibility for comparative simplicity and improved performance"

    Anyone know which part of the full OS binary compatibility was traded?

    1. Re:Xen traded full OS compatibility... by Al+Dimond · · Score: 4, Informative

      To put it simply (I don't know the more in-depth stuff off the top of my head) Xen won't run an unmodified x86 OS as a guest (DomU). Instead of actually emulating the physical devices it provides ways for the guest OSes to request services from it through specialized "drivers", for one thing. Once the kernel/driver work is done, however, the fact that you're running under Xen does not affect your userspace apps.

      So you can only run operating systems that have been modified to run under Xen. So far Linux, FreeBSD, NetBSD and Plan9 have undergone modification, at least according to http://wiki.xensource.com/xenwiki/OSCompatibility

    2. Re:Xen traded full OS compatibility... by buddha42 · · Score: 5, Informative

      This is no longer true with the use of Intel's VT or AMD's Pacifica CPU features. Xen originally had to have this OS-level hack because of limitations of the x86 architecture making it impossible to completely virtualize. Intel and AMD have solved this. You can buy Pentium 4's with VT *right now* and run un-modified windows guest's on Xen. The AMD M2 and the next set of Intel chips (the core/core-duo's desktop and server cousins) will all support this.

    3. Re:Xen traded full OS compatibility... by Anonymous Coward · · Score: 0

      To say there is FreeBSD support is as useful as saying there is SuSE support.

      The FreeBSD Support was on an old version of 5, and it was for one release of Xen. SuSE has it on the install disk, but it didn't work, no matter how many different machines had it installed.

    4. Re:Xen traded full OS compatibility... by Al+Dimond · · Score: 2, Interesting

      I haven't really been able to find much information on this, so maybe you know: with Xen 3 and the VT extentions does the guest OS still need special drivers? It seems to me that there would still be a performance advantage to having special drivers rather than having to virtualize devices. But maybe there's some clever trick in the VT extensions that I'm not taking into account.

  16. Huh? by Anonymous Coward · · Score: 0

    You haven't explained how virtualization avoids RPM hell.

    1. Re:Huh? by peterfa · · Score: 1

      I didn't, no. I was just making a point that RPM is a pain in the neck.

  17. it already is. by nietsch · · Score: 4, Informative

    Only the technology is named User Mode Linux (UML) instead of Xen. Xen still requires you to jump trough quite a number of hoops before you have a virtual machine running. With UML it is so simple you can start, stop & create new ones on demand like is done at linuxzoo.net

    With xen you need a modified host kernel and do some tricky stuff with LVM to use Copy on write disks. With lvm it is the default, you can just point to a base image and have the users modifications in a separate file. The downside is the speed penalty: UML is 40-50% slower than Xen.

    --
    This space is intentionally staring blankly at you
    1. Re:it already is. by Anonymous Coward · · Score: 1, Informative

      Xen is way more flexible and has way greater performance than UML. Although you do have to patch the kernel in order to use Xen, your comment could be interpreted as if you were *forced* to use LVM and COW with Xen. This is, however, misleading - neither of these possible options are /default/.

      Your 40-50% figure is also highly misleading. When operations are I/O-bound, UML can lose to Xen by a factor of 100, but when it's CPU-bound, the overhead of either method is neglegible.

    2. Re:it already is. by nietsch · · Score: 1

      ok, since you did not understand the first time round: show me the command to use a copy-on-write disk with the filesystem in base.img.
      That you twist the advantage of COW into 'COW is hard but you don't have to use it' is your own special debating style I guess.

      --
      This space is intentionally staring blankly at you
    3. Re:it already is. by eno2001 · · Score: 3, Insightful

      For all intents and purposes Xen is the far better solution. I was looking for an alternative to VMWare and I did look over UML. The slow performance of UML alone was a major issue for me and I'm certain a lot of other people here would agree. Plus a lot of us aren't just virtualizing dumb services like Apache. We're virtualizing PVRs, Asterisk PBXs and GNOME or KDE application servers. Xen does that without breaking a sweat. It might be a bit more difficult to set up (not that hard if you know how to compile your own kernel) than UML, but the benefits are far greater. UML cannot, for example, virtualize a 3D accelerator card. Xen can as long as the driver is open. I dont believe you can assign a UML session to only use specific real hardware in your box (this is hand for running multiple PVRs on the same box with multiple video capture cards). And UML definitely can't do a live migration from one physical host to another with NO downtime. That's right. I can have VM1 running on HOST-A, but... I need to take HOST-A down for some repairs and I don't want the services on VM1 to stop. So... I set up HOST-B to take over for HOST-A and tell VM1 to migrate from HOST-A to HOST-B. Type a simple command and it's done. VM1 is now fully running on HOST-B and I can down HOST-A with NO impact to users. The only other thing you need is centralized storage (which anyone doing VMs SHOULD be using. Lookup GNBDs and NBDs.) on a separate host and all hosts must exist in the same network.

      Xen is one of the best virtualization platforms our there and with the support of AMD's Pacifica and Intel's Vanderpool, it will even support running (yuck) Windows VMs when you need to. Sorry, but Xen is lightyears ahead of UML unless all you intend to host is some simple internet services.

      --
      -"...bad old ideas look confusingly fresh when they are packaged as technology" - Jaron Lanier (Digital Maoism on Edge.o
    4. Re:it already is. by Hackeron · · Score: 2, Insightful

      What are you talking about? - XEN is /*virtualization/*, sure its more than an advanced chroot, but it lacks security because there is no real isolation from the underlaying kernel and it requires you to jump through hoops to get going (ok, nice that Redhat bundle it, true).

      UML on the other hand is /*emulation/* -- its like comparing wine to vmware. Apples to Oranges.

      UML has far superior isolation from the underlaying kernel, it runs entirely in userspace so no jumping through hoops, and it is the same speed as XEN for CPU bound applications like number crunching (although much slower for I/O bound applications).

      So each has major advantages/disadvantages but for a mission critical server, I would choose UML every time.

    5. Re:it already is. by eno2001 · · Score: 2, Interesting

      Most Linux users aren't running mission critical servers, but are doing much more interesting things. True, Linux is my choice of OS for running web servers, mail, DNS and the like, but that's hardly important stuff. The really interesting stuff is to be had in the multimedia and desktop arenas and that's where Xen is truly the better performer. I'd far rather run my home remote desktop server on Xen and be able to have my desktop ALWAYS on via VNC even if I have to take the hardware down rather than have a PC for each user in the house. I'd also like to know that my CPU cycles are being well used rather than wasted on emulating parts of a system that really work better when virtualized. Don't get me wrong, things like QEMU have their place. I use it extensively for building VMs before porting them to Xen. I also use it for testing out ISOs of new distros. Hell, I'm even currently running my home web server/mail server/DNS server on QEMU and it's smashingly good. But that was done only to free up the original box that installation sat on. I moved the entire installation to QEMU just using rsync so that I retained everything I'd worked hard on in the VM image. I only needed to make a few tweaks (different NIC). But that was done so I could set my box up with Xen and migrate to new, more MOBILE VMs. That is the key. Xen is much more mobile. It takes just a few minutes to get an entirely new VM running and completely with the feel of a real server running at the native speed of the physical host. No slowdowns at all.

      --
      -"...bad old ideas look confusingly fresh when they are packaged as technology" - Jaron Lanier (Digital Maoism on Edge.o
  18. Re:Modules that work with different kernel version by toggles · · Score: 0

    Be very careful! I've been looking into building a computer specifically for playing with Xen, what I have found out is while the Intel product doc's say VT enabled chip, it isn't actually turned on yet...

    http://www.channelregister.co.uk/2006/02/08/intel_ enables_xeon_vt/

    As far as I can tell AMD hasn't released their pacifica chips yet.

  19. Video explaining Xen by Anonymous Coward · · Score: 0


    "An Introduction to Xen - a virtual machine monitor for x86 compatibles"
    Given at the Hampshire (England) LUG AGM last year.

  20. Modified kernel vs. modified chips by hpcanswers · · Score: 2, Informative

    Xen works with any OS as long as either the kernel has been modified to fit virtualization, or the processor has extensions that support it directly. So either way, Xen allow just any old system, though it isn't tied to a particular platform.

    Just a word of caution though: Xen is "new technology," which basically means it isn't the most stable product right now, especially given its level of technical sophistication. Similarly, the new processors from AMD and Intel are, well, new; they will require some time in the market before they are used adequately.

    All in all though, the technology is pretty exciting. Some researchers I work with are looking into using Xen on SMPs with multiple Ethernet ports. Since vanilla Ethernet requires the kernel for TCP, multiprocessors tend to have trouble adequately using the multiple communication links. With virtualization though, there can be one instance of the OS per processor, which means one TCP stack per processor, which means one Ethernet port per processor.

    1. Re:Modified kernel vs. modified chips by Alioth · · Score: 1

      I'd disagree there on the 'new and unstable' meme; I've been running production servers with Xen for over a year now. It has never crashed.

  21. Modified kernels vs. VT / Pacifica by Anonymous Coward · · Score: 0

    Even with hardware virtualization support, a modified guest kernel with paravirtualization support should see a performance gain over a native, unmodified kernel. The goal is that both methods would be faster than traditional, software-based virtualization or emulation techniques, however.

    With modified kernels readily available, you're likely to see them for FSF Free Software platforms (GNU/Linux, BSD, etc.), for quite some time.

  22. Solaris too (soonish) by PCM2 · · Score: 1

    There's also a project to port Xen to OpenSolaris.

    --
    Breakfast served all day!
  23. Xen + Mosix=? by soldack · · Score: 1

    I have been thinking that it would be interesting to have virtualized operating systems running over a distributed system. All the resources of the distributed system could then be shared amongst the hosted OSs. You could move resources from one hosted OS to another as needed. If things are too slow, just add another system in the distributed system and its resources help the hosted systems.
    -Ack

    --
    -- soldack
  24. related question: running Office on Linux by LazyBoy · · Score: 1
    I'm a Linux user who occasionally boots a Windows machine just to view/print a Word doc or Powerpoint. They always seem to look like ass in Open Office.

    What VMM should I be looking at, vmware, Xen, or something else?

    --

    If Chaos Theory has taught us anything, it's that we must kill all the butterflies.

    1. Re:related question: running Office on Linux by smarinz · · Score: 1

      Hey, I had the same issue as you (Linux User trying to boot a Windows machine in order to use MS Office applications). I actually found a relatively new virtualization program called Parallels Workstation. I didn't want to spend a bunch of money since I wasn't going to be running Windows too often, so I was hesitant to buy VMware's version, since it costs close to $200! Parallels only costs $49, and you can download a fully functional 45-day trial version from the website (http://www.parallels.com./ After using it for like two days, I just went ahead and bought it. Best 50 bucks I've ever spent: it's simple to use, quick, and does exactly what I need it to do. Highly recommended. Good luck!

  25. Ah: also Wine and Crossover Office by HishamMuhammad · · Score: 1

    I thought at first you wanted full-system emulation, so that's why I mentioned QEMU. If you specifically want "only Office" and not a full Windows session, there's Wine (winehq.com). Office runs integrated in the Linux desktop then. Compatibility varies from version to version, but tends to get progressively better. Personally, I only tried Wine with Word Viewer (the free download from microsoft.com) and that was many years ago; on my non-thorough tests it worked perfectly even back then.

    There's a company who sells a proprietary extension of Wine called 'Crossover Office' which specifically adds tweaks to improve Office compatibility in Wine -- I know a few satisfied users.