Frequently Asked Questions
I. General
1.1 What is the Managed Runtime Initiative?
1.2 What is the enhanced Java runtime project (“MRI-J”)?
1.3 What is the enhanced Linux project?
1.4 Who created the Managed Runtime Initiative?
1.5 What are the future plans for the Managed Runtime Initiative?
1.6 What license is the enhanced OpenJDK runtime project and enhanced Linux project released under?
1.7 Is there a Managed Runtime Initiative mailing list?
II. Building, Developing and Packaging
2.1 What packages are required?
2.2 What distributions/platforms do the enhanced OpenJDK runtime and enhanced Linux projects build on?
2.3 How can I contribute to Managed Runtime Initiative projects?
2.4 Is there a Managed Runtime Initiative bug tracker?
2.5 What format is code available?
III. Problems when building
3.1 My build failed
IV. Functionality and Testing
4.1 What does and doesn't work in the enhanced OpenJDK runtime?
4.2 What does and doesn't work with the Linux enhancements?
I. General
1.1 What is the Managed Runtime Initiative?
The Managed Runtime Initiative is a software development and integration initiative launched by Azul Systems with the aim of improving the execution of managed runtimes (.e.g. Java, Ruby, .Net) by enhancing interfaces and functionality across vertical components of the systems stack (e.g. managed runtime, OS kernel, hypervisor and hardware layer). The initiative will encompass multiple projects, some of which are based on open source software, which promote performance and scalability improvements through innovations and extensions across the layered interfaces in the systems stack.
1.2 What is the enhanced OpenJDK runtime project (“MRI-J”)?
The enhanced OpenJDK runtime project (“MRI-J”) and reference implementation contributed by Azul Systems is an enhanced OpenJDK runtime which demonstrates how highly optimized modules working in concert across enhanced interfaces in the system stack can achieve dramatic performance and scalability improvements. The first release (version 0.9) includes a fully functional Java Virtual Machine (JVM) based on an enhanced version of OpenJDK 6. Core capabilities of JVM include pauseless garbage collection and two orders of magnitude (100x) increase in object allocation rate (and supported heap size) for dramatically improved scalability and consistency.
1.3 What is the enhanced Linux project?
The enhanced Linux project and reference implementation contributed by Azul Systems provides a set of enhanced loadable Linux kernel objects (LKOs) that expose new functionality and interfaces which are needed and used by the enhanced OpenJDK runtime project. LKOs are provided for new virtual memory subsystem, physical memory subsystem, and resource scheduler functionality. The LKOs include capabilities which support garbage collection, high virtual memory allocation and manipulation rates, and policy enforcement. Changes are also provided to the Linux kernel to add hooks that enable the LKOs.
1.4 Who created the Managed Runtime Initiative?
The Managed Runtime Initiative was created by Azul Systems.
1.5 What are the future plans for the Managed Runtime Initiative?
The Initiative promotes runtime innovations at a holistic level (i.e. from the managed runtime to operating systems and underlining hypervisor and hardware layer). This requires new implementations and enhanced interfaces across vertical components of the systems stack which encompass both open source projects (e.g. OpenJDK, Linux, KVM) and closed source products (e.g. Windows, Solaris, VMware). Since these layers in the systems stack can be governed by different licensing models and OSS submission processes, the focus will be to (1) define interface enhancements across vertical components and (2) develop and mature new implementations for enhancing performance and scalability which can in turn be upstreamed into existing and complementary OSS projects (e.g. kernel.org, openjdk.org).
1.6 What license is the enhanced OpenJDK runtime project and enhanced Linux project released under?
The enhanced OpenJDK runtime project and enhanced Linux project are both released under the GPL v2 + Classpath exception, which is the same license as OpenJDK and Linux.
1.7 Is there a Managed Runtime mailing list?
We currently have two lists. As other projects are established, there will be additional lists added to support those communities.
II. Building. Developing and Packaging
2.1 What packages are required?
See README files
2.2 What distributions/platforms do the enhanced OpenJDK runtime and enhanced Linux projects build on?
The initial builds for the enhanced OpenJDK runtime and enhanced Linux projects are for x86-64 platforms. The enhanced Linux project is based on a 2.6.32 Linux kernel.
2.3 How can I contribute to the Managed Runtime Initiative?
We will be working to ensure that we have the broadest participation from the community, but at the same time we must minimize any risks to the open projects and to our community due to inappropriate contributions of the intellectual property of others.
A good first step is join our mailing lists (e.g. dev@www.ManagedRuntime.org )
2.4 Is there a Managed Runtime Initiative bug tracker?
We currently have not deployed a bug tracking systems for the project, but anticipate doing so when the 1.0 release is pushed to the download site in the second half of 2010.
2.5 What format is code available?
Currently, the enhanced OpenJDK runtime is available as a tar file containing an enhanced version of OpenJDK6 x86-64. An additional tar file is available containing the enhanced loadable Linux kernel objects (LKOs) and a set of core kernel modifications that provide the LKO “hooks” in the kernel. See the download section for more information.
III. Problems When Building
3.1 My build failed
The components have been tested to build and function correctly only against the specific versions of the tools and build environment described in the instructions. Please make sure that you are using all the specific versions described and accurately following the instructions.
IV. Functionality and Testing
4.1 What does and doesn't work in the enhanced OpenJDK runtime?
The components were tested to build and function correctly only against the specific versions of the tools and build environment as described in the documentation. While the initial release is intended to demonstrate the scalability and performance benefits of the new interfaces and functionality in the systems stack, it only supports a limited set of simple Java applications. Throughout 2010, it is anticipated that further releases to the enhanced OpenJDK runtime project and corresponding kernel modules will provide a more complete and robust solution.
4.2 What does and doesn't work with the Linux enhancements?
The Linux enhancements have been tested against the enhanced OpenJDK runtime in a limited manner for a set of simple Java applications. No other testing has been performed, such as testing of non-Java applications.