Skip to content


Xen 4.0 Feature List

Here is the complete Xen 4.0 feature list:

  • Better performance and scalability: 128 vcpus per guest, 1 TB of RAM per host, 128 physical CPUs per host (as a default, can be compile-time increased to lots more).
  • blktap2 for VHD image support, including high-performance snapshots and cloning. Wiki link: blktap2
  • Improved IOMMU PCI passthru using hardware accelerated IO virtualization techiques (Intel VT-d and AMD IOMMU). Wiki links: XenPCIpassthrough and VTdHowTo
  • VGA primary graphics card passthru support to an HVM guest for high performance graphics using direct access to the graphics card GPU from the guest OS. Wiki links: XenVGAPassthrough
  • TMEM allows improved utilization of unused (for example page cache) PV guest memory. more information: http://oss.oracle.com/projects/tmem/
  • Memory page sharing and page-to-disc for HVM guests: Copy-on-Write sharing of identical memory pages between VMs.This is an initial implementation and will be improved in upcoming releases.
  • New Linux pvops dom0 kernel 2.6.31.x as a default, 2.6.32.x also available. You can also use linux-2.6.18-xen dom0 kernel with Xen 4.0 hypervisor if you want. Wiki link: XenDom0Kernels
  • Netchannel2 for improved networking acceleration features and performance, smart NICs, multi-queue support and SR-IOV functionality.
  • Online resize of guest disks without reboot/shutdown.
  • Remus Fault Tolerance: Live transactional synchronization of VM state between physical servers. run guests synchronized on multiple hosts simultaneously for preventing downtime from hardware failures.
  • RAS features: physical cpu/memory hotplug.
  • Libxenlight (libxl): a new C library providing higher-level control of Xen that can be shared between various Xen management toolstacks.
  • PV-USB: Paravirtual high-performance USB passthru to both PV and HVM guests, supporting USB 2.0 devices. Wiki link: XenUSBPassthrough
  • gdbsx: debugger to debug ELF guests
  • Support for Citrix WHQL-certified Windows PV drivers, included in XCP (Xen Cloud Platform). Xen Cloud Platform: http://www.xen.org/products/cloudxen.html
  • Pygrub improvements: Support for PV guests using GRUB2, Support for guest /boot on ext4 filesystem, Support for bzip2- and lzma-compressed bzImage kernels
  • And more..

Thanks again to the Xen.org community for their outstanding efforts in developing this important community release.


Be Sociable and Share!

Posted in Community, Xen Development, Xen.org Promotion.

Tagged with , .


2 Responses

Stay in touch with the conversation, subscribe to the RSS feed for comments on this post.

Continuing the Discussion

  1. Xen.org Weekly Newsletter Vol 10 No 15 – blog.xen.org linked to this post on April 16, 2010

    [...] Xen 4.0 – Feature List – http://blog.xen.org/index.php/2010/04/13/xen-4-0-feature-list/ [...]

  2. Xen and the Art of Virtualization – 2010 Edition | The Virtualization Blog linked to this post on April 23, 2010

    [...] the effort to have Xen provide support for our CPU and GPU technologies.  Here are some of the key enhancements that stand out to us and provide solid support for our new AMD Opteron™ 6000 series [...]

You must be logged in to post a comment.