Xen Hypervisor - Leading Open Source Hypervisor for Servers
Enterprises looking to increase server utilization, consolidate server farms, reduce complexity, and decrease total cost of ownership are embracing server virtualization. The Xen® hypervisor is the fastest and most secure infrastructure virtualization solution available today, supporting a wide range of guest operating systems including Windows®, Linux®, Solaris®, and various versions of the BSD operating systems.
With Xen virtualization, a thin software layer known as the Xen hypervisor is inserted between the server's hardware and the operating system. This provides an abstraction layer that allows each physical server to run one or more "virtual servers", effectively decoupling the operating system and its applications from the underlying physical server.
The Xen hypervisor is a unique open source technology, developed collaboratively by the Xen community and engineers at over 50 of the most innovative data center solution vendors, including AMD, Cisco, Dell, Fujistu, HP, IBM, Intel, Mellanox, Network Appliance, Novell, Red Hat, Samsung, SGI, Sun, Unisys, Veritas, Voltaire, and Citrix. Xen is licensed under the GNU General Public License (GPL2) and is available at no charge in both source and object format. Xen is, and always will be, open sourced, uniting the industry and the Xen ecosystem to speed the adoption of virtualization in the enterprise.
The Xen hypervisor is also exceptionally lean-- less than 150,000 lines of code. That translates to extremely low overhead and near-native performance for guests. Xen re-uses existing device drivers (both closed and open source) from Linux, making device management easy. Moreover Xen is robust to device driver failure and protects both guests and the hypervisor from faulty or malicious drivers.
Xen Hypervisor 4.1.1 Download
The Xen 4.1 release contains a number of important new features and updates including:
- A re-architected XL toolstack that is functionally nearly equivalent to XM/XEND
- Prototype credit2 scheduler designed for latency-sensitive workloads and very large systems
- CPU Pools for advanced partitioning
- Support for large systems (>255 processors and 1GB/2MB super page support)
- Support for x86 Advanced Vector eXtension (AVX)
- New Memory Access API enabling integration of 3rd party security solutions into Xen virtualized environments
- Even better stability through our new automated regression tests
- Xen 4.1 Release Notes
- Xen 4.1 Datasheet
Xen 4.1.1 is a maintenance release in the 4.1 series and contains:
- Security fixes including CVE-2011-1583 and CVE-2011-1898
- Enhancements to guest introspection (VM single stepping support for very fine-grained access control)
- Many stability improvements, such as:
- PV-on-HVM stability fixes (fixing some IRQ issues)
- XSAVE cpu feature support for PV guests (allows safe use of latest multimedia instructions)
- RAS fixes for high availability
- fixes for offlining bad pages
- changes to libxc, mainly of benefit to libvirt
- Compatibility fixes for newer Linux guests, newer compilers, some old guest savefiles, newer Python, grub2, some hardware/BIOS bugs.
