Xen community releases Xen 4.1 hypervisor

Latest open source Xen virtualization platform is more scalable, has better toolsets, and improves security with APIs for third-party integration

There's good news for organizations that prefer the Linux-based, open source Xen hypervisor over competing virtualization offerings such as KVM, QEMU, VirtualBox, or the market-leading VMware platform. After nearly a year in development, Xen 4.1 has been released, providing updates and enhancements over the previous 4.0 version.

In spite of Xen 4.1 being a minor dot release, this project was no small feat. To put things into perspective, Lars Kurth, the recently appointed Xen.org community manager, stated that there were 102 individuals and 25 organizations that helped make Xen 4.1 possible by contributing more than 1,900 commits to the Xen codebase. There were also 60 individuals who made just over 400 commits to the Xen subsystem and drivers in the Linux kernel.

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The Xen community has updated its hypervisor to provide greater scalability, a better toolset, and improved integration with third-party security solutions. At the same time, the Xen development community has been working more closely with upstream Linux distributions to ensure that Xen dom0 support and Xen guest support is available from unmodified Linux distributions, making using and installing Xen much easier than it was in the past.

Key features found in this latest Xen 4.1 release include the following:

  • A re-architected XL toolstack that is functionally equivalent and almost entirely backward-compatible with existing XM domain configuration files. It is based on the new libxenlight library and provides a simple yet robust API.
  • A new prototype credit 2 scheduler, completely rewritten and designed for latency-sensitive workloads (network traffic and audio) and a very large number of CPUs.
  • CPU pools providing for advanced partitioning and allocating virtual machines. Each CPU pool runs its own scheduler, which can either be credit 1 or credit 2.
  • Extended and optimized support for new hardware features to increase performance and scalability for large systems, including systems with more than 255 processors and 1GB/2MB super page support.
  • Support for xsave and xrestor floating point instructions, enabling Xen guests to utilize Advanced Vector eXtension (AVX) instructions available on newer Intel Sandy Bridge or AMD Bulldozer processors.
  • A new Memory Access API, which enables suitably privileged domains to intercept and handle memory faults and provides integration for third-party security solutions to invoke malware detection from outside the virtual machine environment.

"The Xen development community recognizes that there is still some way to go," said Kurth. "Thus, we will continue to work with upstream open source projects to ensure that Xen works out of the box with all major operating systems, allowing users to get the benefits of Xen such as multi-OS support, performance, reliability, security, and feature richness without incurring the burden of having to use custom builds of operating systems."

When you are ready, you can begin your journey by downloading the latest Xen 4.1 hypervisor and tools from the Xen.org community.

This article, "Xen community releases Xen 4.1 hypervisor," was originally published at InfoWorld.com. Follow the latest developments in virtualization and cloud computing at InfoWorld.com. For the latest business technology news, follow InfoWorld.com on Twitter.