Release: Xen 4.1, the community which develops the Xen hypervisor under the GNU General Public License (GPLv2) has released version 4.1, this version is the follow-up of version 4.0 which was released in April last year.

Xen is a virtualization engine, used by several Linux distributions, NetBSD and Solaris but also serves as a basis for the Xen Cloud Platform (XCP) and Xen Hypervisor for Client Devices (XCI) for example, which will probably include a new version of Xen in a future release. Also Citrix XenServer which derives from XCP and Citrix XenClient which derives from XCI use Xen.

Version 4.1 adds the following new features:

  • A re-architected XL toolstack that is based on the libxenlight library and provides functionally nearly equivalent to XM domain configuration files/XEND
  • Prototype credit2 scheduler designed for latency-sensitive workloads and very large systems, although the scheduler is functional and stable, its algorithm need further fine-tuning before it will become Xen’s main scheduler
  • CPU Pools for advanced partitioning, each CPU pool runs its own scheduler (credit 1 or credit 2)
  • 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
  • Better stability through new automated regression tests