virtualization.info Editors

InfoWorld published a brief review of SWsoft Virtuozzo for Linux 3.0, giving it a score of 9.3 (Excellent) and writing this bottom line:

SWsoft really has its ducks in a row with Virtuozzo for Linux 3.0. It’s a well-designed and well-implemented virtualization solution that comes at a surprisingly low cost. Because it’s not true hardware virtualization and relies heavily on the host OS, it’s not for everyone, but it’s an outstanding choice for companies such as hosting providers and large infrastructures.

There is a point particularly interesting to me. The author, Paul Venezia, claims Virtuozzo has a much lower overhead than VMWare solution:

…
SWSoft’s approach to server virtualization has some definite benefits over VMWare?s. Among them, it requires much less overhead, so more virtual servers can be run from a single server without noticeable performance degradation…

But there are no traces of benckmarks or even a detail about VMware platform used for comparison, so beware of such affirmations.

Read the whole review at source.

If you are interested in Virtuozzo you could read the virtualization.info Review of SWsoft Virtuozzo for Windows 3.5.1.

After reading this article and this article about current controversy between VMware and Xen on how to implement virtualization in the Linux kernel, I believe it’s meaningful to quote the original VMware proposal:

…
Unlike the full-virtualization techniques used in the traditional VMware products, paravirtualization is a technique where the operating system is modified to enlighten the hypervisor with timely knowledge about the operating system’s activities. Since the hypervisor now depends on the kernel to tell it about common idioms etc, it does not need to write protect OS objects such as page and descriptor tables as a solution based on full-virtualization needs.
This has two important effects (a) it shortens the critical path, since faulting is expensive on modern processors (b) by eliminating complex heuristics the hypervisor is simplified. While the former delivers performance, the latter is quite important too.

Not surprisingly, paravirtualization’s strength, ie that it encourages tighter communication between the kernel and the hypervisor, is also its
weakness. Unless the changes to the operating system are moderated, you can very quickly find yourself with a kernel that (a) looks and feels like a brand new kernel or (b) cannot run on native machines or on newer versions of the hypervisor without a full recompile. The former can impede innovation in the Linux kernel, and the latter can be a problem for software vendors.

VMware proposes VMI as a paravirtualization interface for Linux that
solves these problems.

• A VMI’fied Linux kernel runs unmodified on native hardware, and on many hypervisors, while simultaneously delivering on the performance promise of paravirtualization.
• VMI has a rich and low level interface, which allows the kernel to cope with future hardware evolution by querying for hardware capability. It is our expectation that a single kernel will run unmodified on both today’s processors with limited hardware virtualization support and also keep up with any evolution on the processor front.
• VMI Linux is a fairly clean interface, with distinct name spaces for objects from the kernel and the hypervisor. Nowhere do we mingle names from the hypervisor with that of the kernel. This separation allows innovation in the kernel to proceed at the same speed as always. For most kernel developers, a VMI kernel looks and feels like a regular Linux kernel.
• VMI Linux still supports “native” hypervisor device drivers, for example a hypervisor vendor’s own private network or block device drivers which are free to use any interface desired to communicate with the hypervisor.

…

Be sure to read the whole ongoing thread for having a complete picture of VMware and Xen positions.

If you are interested you can find the draft VMI documentation inside the thread here.

I already mentioned another article about this topic 2 weeks ago, but The Register wrote a very complete and interesting follow-up:

…
“VMware have proposed an implementation that would allow, in theory, different kinds of hypervisors to run beneath the kernel,” Morton said, in an interview with The Register. “It is, if you like, a hypervisor-neutral interface. The question remains if we want to have a hypervisor neutral interface. There might be the case that this generic interface isn’t going to buy us anything, so maybe we will just merge with Xen.

“That decision has not yet been made. We need to step back and have a think about how we are going to do this.”

Morton admits that he knows “very little” about the inner-workings of hypervisors – the core software layer used by some to manage virtual servers. With that in mind, he wants to see VMware and Xen developers hammer out the interface issue without involvement from him or Linus Torvalds.

“Any time Linus or I have to make a decision, the system has failed,” he said, noting that the kernel crew is eager to see this particular issue resolved.

The major problem, however, is that VMware and Xen developers don’t seem very close to having a meeting of the minds

The two camps have debated VMI for months on Linux kernel mailing lists, with other developers from IBM, Red Hat, Oracle and elsewhere chiming in.

“Most of our interactions have been on that level,” VMware senior director of research and development Jack Lo said.

VMware has reached out to the OSDL (Open Source Development Labs) and other unnamed parties to help set up a public forum for discussing the interface issue with Xen backers and anyone else who wants to show up.

But, after interviewing a number of people for this story, we get the sense that such a meeting is a concept at best right now. The parties involved proved reticent to nail down a time when they actually plan to sit down and don’t seem all that determined to approach a debate until all the behind-the-scenes political posturing has taken place…

I strongly suggest to read the whole article.

Ben Armstrong provided another script to programmatically change the boot order inside Virtual Server 2005 virtual machines.

Read it here.

Quoting from CNET News:

…
Harald Welte, the lead programmer of the netfilter/iptables firewall software used in Linux, griped last week on his blog that the software didn’t support the next-generation IPv6 Internet standard.

Welte’s complaint didn’t fall on deaf ears. “We have listened to the community and appreciate the feedback and will implement IPv6 support in OpenVZ in a month or two,” SWsoft said in a statement…

Read the whole article at source.

Before buying a new server/desktop/laptop it’s quite obvious for a company or a single IT professional checking if it will sport new generation AMD/Intel CPUs.
Among most desirable features there is virtualization extension, but not every new processor on the market will have it.

The Register reported the expected low-end Pentium D 9xx processor family Intel will possibly release 3Q 2006 will not have Virtualization Technology (VT) enhancement:

…The 925 and 915 are clocked at 3.0GHz and 2.8GHz, respectively. Both contain twin 2MB L2 caches, run over an 800MHz frontside bus and support 64-bit addressing. In addition to VT, they don’t feature Enhanced SpeedStep – both technologies are present in higher-end 9xx-class Pentium Ds…

Read the whole article at source.

While working on its Workstation 2.1 for Apple Mac OS X on Intel architectures, Parallels is launching another beta program for a very useful tool: the VM Compactor 1.0.

Parallels claims this tool is able to compact size of a virtual machine of up to 80% and it works with any Microsoft Windows XP/2000/2003 virtual machine created with most known virtualization platforms:

• Microsoft Virtual PC and Virtual Server
• Parallels Workstation
• VMware Workstation, GSX Server and Server

Download it here.

Even if it actually has no competitors, Parallels continues its marathon to be the first virtualization vendor to release a product on the new Apple Mac OS X for Intel architectures.

This new beta fixes several problems, improve performances and user experience, and introduces following features:

• Full-screen mode
• Dual-monitor support

Download it here.

Macworld published a very interesting review of how Parallels Workstation 2.1 beta 3 is performing on a Apple Mac mini powered by an Intel Core Duo.

The review is particularly interesting cause it details in a very objective way what works and what not, while trying to work with Microsoft Windows XP and 2000, Debian and Fedora Core Linux.

Read it at source.

Quoting from WindowsForDevices:

TenAsys is developing a real-time virtual-machine manager based on the built-in virtualization technology extensions of Intel’s new multi-core processors. TenAsys says its RT-Hypervisor, available later this year, will isolate multiple operating environments on an Intel processor, ensuring real-time determinism and improved control over hardware and interrupt resources for “guest” RTOSes (real-time operating systems).
…
RT-Hypervisor will implement an “early boot” mechanism that creates a transparent virtual machine layer that treats all operating systems, including Windows, as “guests” OSes. The companion RTOSes could be Windows CE, VxWorks, or even “legacy” applications that don’t require an OS…

Read the whole article at source.