Xen is een virtuele machine monitor voor het x86-platform en laat meerdere besturingssystemen gelijktijdig op één systeem draaien zonder de prestaties drastisch te beďnvloeden. Wie wil weten hoe de ontwikkelaars Xen hebben bedacht en ontworpen kan hier de documentatie na lezen. Op dit moment wordt alleen Linux en *BSD ondersteund als besturingssysteem maar men is druk bezig met andere bedrijven om ook andere besturingssystemen te ondersteunen zoals Solaris. De ontwikkelaars van XenSource hebben versie 3.0 uitgebracht waar ondersteuning voor 32-way SMP, 64-bit guests, en Intel Virtualization Technology worden toegevoegd. De persaankondiging ziet er als volgt uit:
XenSource, Inc., the leader in infrastructure virtualization solutions based on the open source Xen hypervisor, today announced the open source community release of Xen 3.0. In its first major release in over a year, the Xen project has delivered a compelling virtualization feature set that is squarely targeted at enterprise infrastructure virtualization needs, focusing on support for symmetric multi-processing (SMP), large server memory configurations and near-native performance, and offering for the first time an ability to virtualize all guest operating systems.
Xen 3.0 supports Intel® Virtualization Technology, which allows virtualized servers to run natively on the processor, exploiting hardware acceleration for CPU and memory virtualization. This support is key to Xen’s ability to virtualize all operating systems. Xen will also support AMD’s Pacifica hardware virtualization early in 2006.
Xen 3.0 also supports up to 32-way SMP virtualized guests, with an ability to dynamically "hot plug" CPUs to ensure best use of available resources. Used in conjunction with Xen's ability to dynamically relocate a running guest from one server to another, this capability enables IT managers to optimally place workload on their available server resources. Additionally, Xen 3.0 offers support for two new addressing modes for servers with large memories: Physical Address Extension (PAE) allows 32-bit servers to address more than 4GB memory, and 64-bit addressing for up to 1TB of memory; and, support for Trusted Platform Modules, which provide hardware based security, attestation and trust, as well as security features contributed from IBM’s secure hypervisor initiative. A port of Xen, to Intel’s Itanium Architecture contributed by HP and Intel is also included, and a port of Xen to IBM’s Power PC architecture by IBM is close to completion, signaling broad cross-platform adoption of Xen.
"This release represents a significant milestone for the Xen community," said Ian Pratt, Xen project leader and XenSource founder. "It is the result of a tremendous community effort, with contributions to date from over 150 developers world wide, and more than 20 major Enterprise infrastructure vendors, as well as the OSDL and ten top tier universities. The fact that Xen is the industry’s fastest and most secure hypervisor for x86 systems is testimony to the depth of our community and power of the open source process. The industry has embraced Xen as an emerging open industry standard for virtualization, for all operating systems."
The community release signals that the code base is functionally complete and ready for further testing and validation by the Xen community. "We have been working hard to make Xen 3.0 available to the major Enterprise Linux vendors so they can begin QA for their next major releases, and to deliver a hypervisor that can exploit hardware virtualization and thus support proprietary operating systems," said Pratt. "Now we are turning our focus to extending our community testing program, hardening, and performance-tuning."
Xen 3.0 is the first major release of Xen since the October 2004 release of Xen 2.0, which saw significant deployment in ASP, retail, hosting and development and testing environments. The new release delivers a feature set needed by large enterprises seeking to adopt virtualization in the data center, to realize the benefits of increased server utilization, server consolidation, "instant on" provisioning of servers and no-downtime maintenance. Virtualization of enterprise servers cuts capital expenditures and personnel costs associated with deployment and management of IT infrastructure. Xen’s ability to instantly deploy a virtual server image on any server dramatically cuts provisioning time – from weeks to seconds – and its live relocation capability enables no-downtime maintenance, high availability and optimal matching of workload to available compute resources.
This release represents the first public availability of the Xen 3.0 code base and feature set to the broader open source Xen community allowing Xen partners and vendors to now begin perform performance testing and quality assurance, stabilization, and development of their Xen-based offerings. Xen 3.0 will be distributed by the leading enterprise Linux distributors, in Novell’s SUSE Linux Enterprise Server, and Red Hat Enterprise Linux. Sun also recently announced plans to offer paravirtualized Solaris on x64 virtual servers running on Xen.