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Red Hat Wants Xen In Linux Kernel
DIY News writes "Red Hat is aggressively pushing to get Xen virtualization technology included in the Linux kernel as quickly as possible. This move comes as Microsoft is pushing its own virtualization products and recently relaxed some of its licensing requirements around Windows Server 2003 to facilitate more pervasive adoption and use of those technologies."
What exactly does "virtualization technology included in the Linux kernel" means?
That you can run virtual machines with that kernel? that that kernel can be hosted into a virtual machine?
Or that you can install parallel kernels and run part of the ELF binaries on the other machine?..
gtkaml.org
Xen isn't all that hard, you just need some jump boots and a particle weapon of some sort.
Well, Xen is free, and Intel/AMD hardware solutions are comming soon, which will allow Xen to run Windows unmodified. So, once everyone is upgraded to the new CPU's, virtualization will become a basic standard feature for everyone. MS can compete by giving their solution away for free, but either way, it doesn't get better than free for the consumer.
Not only do they get the ability to knock the shit out of Microsoft, by taking away the base platform from them, they also get to try to get some market share from VMWare.
Imagine if you would the ability to use Xen for unlimited operating systems, no licensing cost of the base OS, thinking about it, I would prefer to be in Microsoft's shoes as opposed to VMWare's. Only difference is that Xen when compared to VMWare is a very immature platform and no IT manager is going to take Xen over VMWare just yet (Unless cost is a BIG factor).
I would have to say that this is still very cool, with all the new Virtualization options come out in the new cores shortly and if they can get to market before Microsoft, this is a great way to pick up some customers. Kudos to RedHat and IBM and Intel and everyone else for making this happen.
Curiosity was framed; ignorance killed the cat. -- Author unknown
"My goal is to get this done in the most collaborative way possible with anyone in the community who wants to participate," Stevens said, adding that Red Hat is committed to putting on this project enough of its staff who have the technical knowledge necessary to get the work done.
Perhaps it's only me, but this doesn't sound aggressive; this sounds friendly and cooperative.
Ask me about repetitive DNA
Why don't they fork? Or just build and rpm their own kernel, like they did with GCC 2.96?
The more advanced the technology, the more open it is to primitive attack
The irony is that Microsoft provided some of the funding for Xen (probably for the early experimental Xenised versions of Windows XP). Yes - Microsoft does fund GPLd projects. Often in a company that big, the left hand doesn't know what the right hand is doing, so whilst Gates/Balmer spout off about how evil open source is, another part of MS is funding it (or even releasing it on Sourceforge).
Oolite: Elite-like game. For Mac, Linux and Windows
*hmmm*
Must remember to patent the idea of trojan/virus that uses visualisation to run a spam/DOS server
in a Windows environment...
Rubs hands with glee as he tries to sell the idea on IRC.
Acid House saves Souls
"While Xen appears as a neat package, why choose Xen instead of vservers?
The hardware cost of running multiple copies of the same OS with vservers is smaller than Xen - there is one and only one copy of glibc in memory, one and only scheduler, and so on."
But part of the purpose of a virtual machine is that you can run a different operating system in each partition, including different schedulers and libc versions.
Mandriva Linux 2006 includes xen0 and xenU-enabled kernels and the Xen supervisor utilities package. The Community version of Mandriva 2006 can be downloaded from many Linux mirror sites.
I'm running such a box now with a total of three Linux domains (one host domain and two guest)... much easier than manually patching everything.
With Xen, a kernel panic effects only that kernel, the other kernels keep on running. Under vservers, it takes down the machine.
Under Xen you can reduce the parent kernel down to obare minimum, reducing the chance of errors.
eg: you want to run an experimental iptable module on one of the virtual servers, no problem, if it crashes, all the other servers keep on trucking.
Essentially Xen provides a better sandbox from a stability/security perspective.
Remember that anything RedHat pushes into the Linux Kernel will automatically become available for ALL OTHER LINUX DISTROS. So please forgive my ignorance, but where is the "badness" in that aim? AFAIK, nothing that RedHat has developed has been proprietary in any way. They do have a track record of buying things from other companies and releasing them as OSS stuff. Again please let me know of the badness in that aim.
IMHO, virtualisation is going to become very important to all sofware developers over the next few years. If it is easy to fire up a Debian system on top of a SUSE and have Mandriva & RedHat running as well then you can test your app on all these platforms at the same time. Hurrah!
I'd rather be riding my '63 Triumph T120.
I still remeber reading that the whole x86 architecture didn't meet the requirements for virtualization, meaning that this recent trend is probably the result of VMware figuring out some "tricks to make it work", and then everyone else jumping on the bandwagon.
In any case, if you really want to learn about the fundamental concepts behind virtualization, I strongly recommend reading the following paper: Formal Requirements for Virtualizable Third Generation Architectures
Yes, it was published in 1974, but most of the concepts are still very applicable and make a lot of sense. (though the architecture examples are obviously dated)
This is a very good paper which lays out all the ground rules. Sure, it may sound a bit academic in terminology and explanation, but it is still quite readable.
The Schrodinger Corp. makes special PC cases that can handle those requirements.
http://www.novell.com/products/linuxprofessional/c omparative.html
This sig kills fascists.
The Slashdot summary is a bit misleading. What the article says is that Andrew Morton has been expecting a kernel submission for Xen for quite some time now but a) has yet to receive it, and b) needs to go through the usual process with other "stakeholders" before any incorporation. Later the article quotes the Xen folks themselves who point out that "feature creep" and the need to generally get things really solid and stable has made everything take a little longer.
What the article actually seems to be saying - it uses the word "agressive" a lot as if this was some kind of virtue - is that Red Hat has a new senior honcho who'd like to make his mark. The issue of incorporating virtualization technologies into the Linux kernel is taken as a given by all parties. Which is hardly news. Chalk one up to the Red Hat marketing department for a nicely planted "news" story about their increased investment in the area (new hires, etc.), perhaps.
Las qué passoun
tournoun pas maï
These guys(Xen) have all these companies donating money to them, but have been beaten to kernel inclusion by UML.
Being the first to the party doesn't always mean you're going to the best; see DevFS vs. udev.
Xen has much greater performance than UML and supports more operating systems. While UML is currently more mature and stable than Xen, it's only a matter of time before Xen surpasses UML as the preferred virtual server technology. Hell, even Linode, a strong proponent of UML technology and virtual server hosting provider is migrating to Xen.
FYI, I'm currently running a Xen-based system with 15 virtual server instances for a system administration course at UC Berkeley on a server built with cheap off the shelf components (AMD Athlon 64 2800+, 1 GB RAM) and everything is quite snappy. It'd be difficult to even approach such usability with UML, and I'm using Xen 2.0.7. I can't see what Xen 3.0 will bring.
I'm Trappped at Berkeley.
Multiple OSes at once? [..] I never got the whole concept of virtual servers
Its mainly an enterprise play.
If you're an old-timer UNIX admin, you may have difficulty understanding the point of server virtualization (i.e. multiple OS instances). In UNIXland, it has been normal and customary for several completely unrelated applications to run under the same OS instance, together servicing thousands of users. That never worked well in Windowsland. That being said, it didn't stop manufacturers from making staggering improvements in performace and capabilities of Intel servers. Companies grew to expect single Intel boxes to perform at the levels of large UNIX servers. The only way to achieve that in recent years has been to use industrial strength virtualization technology (basically, ESX). The boxes are beefier than ever, and ESX isn't cheap, but it works wonders.
For $50k, you can run 50 VMware guests on one very beefy box (not counting SAN), but you'd want a second for failover. For $75k, you can run about 100 guests on 14 blades in 7U (again, not counting SAN) and have the guests automatically migrate to the blades most able to run their workload at that moment in time. Ask a blade to come down for maintenance, and all the guests scatter to other blades before the blade powers off. Replaced a dead blade with a blank? Your systems management policies detect the new blank and automatically install ESX on it so guests can migrate back and evenly spread out the load.
Sounds crazy, I know, but that's a taste of what we're doing in the enteprise space these days.
Intelligent Life on Earth
There are a few problems with Xen. First, it's i386 only. Second (and this is the biggest problem IMO) - Xen is venture-backed, and seems to be extremely eager to show their investors a return. Nothing wrong with that, but it's important to consider the motivation, and the consequence of a funding pull back. If XenSource does not turn out to be a great business, then will Xen still be developed and maintained? Why not wait a little bit, in the open source world quality over quantity matters and time pressure should not influence development.
Also, there is another project that I plug every chance I get - Linux Vserver. Unlike Xen, this is a purely volunteer effort, and is very innovative and attemtps to solve a difficult issue. Unlike Xen, these guys actually do not want to be in the mainline for now, becuase they think it will slow down development. Because Linux VServer is taking a different approach to virtualization (better known as separation, which was pioneered by FreeBSD jails and is also now supported in Solaris), the end result is cross-platform, i.e. runs on any architecture that Linux runs on.
Now in the past whenever I posted about Linux VServer a lot of folks said that Xen allows you to run multiple operating systems and that that is why it is so useful. I think that in reality running multiple OS's isn't all that valuable - the only case where it may be very useful is software development, but that's a tiny fraction of the Linux users. We've been using Linux VServer for hosting, and we are absolutely convinced that this is the right solution - for using Xen for example would introduce all kinds of problems (starting with resource bloat).
Yet unfortunately the OSS world has become PR driven lately. Very few people are technically capable of looking at things based on its merits and just go after the things that have the most buzz, not realizing that the buzz is artificially generated.
The full x86 architecture is not suitable for virtualization, because there are a few instructions which fail silently when run from user level.
VMware uses various techniques to get around this, including full simulation and binary re-writing.
Xen uses another approach, where they port to an instruction set that is basically x86 without the problematic instructions. This approach requires that the guest OS's be modfied.
This will all change with the new virtualization instructions being added by both AMD and Intel. Once that is in place, Xen will be able to run unmodified guest OS's (such as Windows, for instance). There will be a speed hit though, so modified guests will be prefered if speed is an issue.