Palacios is an open source virtual machine monitor developed as part of the V3VEE Project and the Hobbes Project.

Palacios is intended to facilitate research and teaching in computer systems, computer architecture, and high performance computing. It is released under the BSD license. Community use and contributions to the source base are strongly encouraged!

The current version of Palacios is the head of the main development branch, which is available below via git or snapshot download. This is probably the version you want.

Hobbes users should instead clone the NVL repository and follow instructions there. The NVL repository contains various components, including Palacios, as submodules as well as additional code that integrates these components together appropriately.

As of version 1.3, the preferred host OS for Palacios is the Linux Kernel. Palacios can be compiled into a kernel module that can then be inserted into existing Linux kernels. Palacios 1.3 can also be readily incorporated into the Kitten Lightweight Kernel, and other OSes.


  • Public git access (Please register below)
    main development branch | release 1.3 branch | release 1.2 branch | release 1.1 branch | release 1.0 branch

  • Other Code
    Externally contributed code (thank you!)
    Palacios/Gem5 Integration

  • Palacios-1.3 (available as source tarball (below)) Latest Version (November 18, 2011)
    announcement | changes | getting started | technical report (manual) | pxe boot
    simple guest | simple multicore guest | compact linux host configuration
    example palacios config | example linux 2.6.37 config
    kitten 1.3.0 is the current kitten host

  • Palacios-1.2 (available as source tarball (below)) (January 28, 2010)
    announcement | changes | simple instructions | manual (pdf)
  • Palacios-1.1 (available as source tarball (below)) (May 1, 2009)
    announcement | changes | using palacios with kitten
  • Palacios-1.0 (available as source tarball and VMWare Image (below)) (November, 2008)
    announcement | release notes
  • Getting Help

  • The Palacios Technical Report is the most important documentation for Palacios 1.3 and later.
  • Release 1.3 has been tested with Kitten 1.3.0, Linux 2.6.32 and several later Linux versions as host OSes. In addition to compact Linux host configurations, we have also tested Palacios in unmodified Fedora 15 environments, and in Red Hat
  • There is also an Open Discussion Group for Developers, as well as a General Open Discussion Group On V3VEE.

  • We ask that you complete the following form to access the code. All fields are optional. By filling out the form, you will help us measure the impact of the Palacios VMM and the V3VEE project.

    Research area (e.g., Palacios):
    Primary use:
    Download type:


    This project is made possible by support from the National Science Foundation (NSF) via grants CNS-0709168 (Northwestern), CNS-0707365 (UNM), and the Department of Energy (DOE) via grant DE-SC0005343 (Northwestern, UNM, U.Pittsburgh, Sandia, and ORNL). Seed funding to help start the development of Palacios at Northwestern was provided via a subcontract from Oak Ridge National Laboratory (ORNL) on DOE grant DE-AC05-00OR22725. Seed funding to help start multicore guest development at Northwestern was provided via a subcontract from Sandia National Laboratories. Jack Lange was partially supported by a Symantec Research Labs Fellowship.