The goal of this Project is to provide a venue to explore and incubate advanced Java VM and Language feature candidates such as:

This Project is sponsored by the HotSpot Group.

Additional Resources

The following provide a sketch of possible features and implementation approaches.

The following is a list of community presentations


How you can help!

If you're new to OpenJDK then it is strongly advised that you join the Adoption Group and learn about OpenJDK before diving into advanced Valhalla topics.


Most theoretical ideas have been well explored by the core Members! The greatest help can therefore be given by those who:

Levels of expertise / suggested participation:

  1. Full Time JVM internals expert / implementer
    Please join the mailing list and produce concrete prototypes, try out the nightly builds and give feedback on existing prototypes.
  2. Java/JVM Language, Framework, Library authors/experts
    Please join the mailing list, try out the nightly builds and give feedback on existing prototypes.
  3. Day to Day Java Developers (or developers using other JVM languages)
    Please join the mailing list and join the Adoption Group to participate in hack days on stable prototypes.

Source Code and Building Valhalla

Valhalla is built the same as most OpenJDK forests, i.e. At the command line execute:
    hg clone valhalla
    cd valhalla
    chmod u+x
    bash configure
    make images
Once you've done this once you only need to repeat the last three commands when you want to update to the latest version.
There is a general OpenJDK build guide if you need help.