Free virtual machines software for linux

The Linux Virtual Server is a highly scalable and highly available server built on a cluster of real servers, with the load balancer running on the Linux operating system.

The architecture of the server cluster is fully transparent to end users, and the users interact as if it were a single high-performance virtual server.

The basic goal of the Linux Virtual Server Project is to:
- Build a high-performance and highly available server for Linux using clustering technology, which provides good scalability, reliability and serviceability.

Caffeine is a free high-performing interoperability solution between the Java platform and the .NET framework.
Caffeines key differentiator is that does not replace the Java Virtual Machine. Instead, your JVM of choice is hosted within the .NET runtime, ensuring that vendor-specific VM optimizations are preserved.
The specific objectives of Caffeine are:
- Run on any combination of .NET runtime (1.0+) and Java Virtual Machine (1.2+).
- Allow full reuse of any Java library from a .NET environment, working exclusively at the API level and avoiding bytecode translation of the actual implementation.
- Provide optimal performance, running the JVM and .NET under the same process and avoiding network or IPC costs.
Caffeine is open source, built for and by developers, and licensed under an MIT/X license that allows Caffeine to be used and/or embedded in commercial software.
Main features:
- Bindings of jobject, jarray, jvalue, jclass, jmethoid, jclassid, jfieldid.
- C# wrapper class generator toolchain from Java library.
- Public and protected classes and methods.
- Inner types, within classes and interfaces.
- Abstract classes and interfaces.
- Object casting.
- Arrays.
- Constants in interfaces.
- Basic temporary interoperability between System.String and java.lang.String.

Joeq is a virtual machine and compiler infrastructure designed to facilitate research in virtual machine technologies such as Just-In-Time and Ahead-Of-Time compilation, advanced garbage collection techniques, distributed computation, sophisticated scheduling algorithms, and advanced run time techniques.
Joeq is entirely implemented in Java, leading to reliability, portability, maintainability, and efficiency. It is also language-independent, so code from any supported language can be seamlessly compiled, linked, and executed -- all dynamically.
Each component of the virtual machine is written to be independent with a general but well-defined interface, making it easy to experiment with new ideas.
Joeq is released as open source software, and is being used as a framework by researchers on five continents on topics ranging from automatic distributed virtual machines to whole-program pointer analysis.
Joeq is a virtual machine and compiler infrastructure designed to be a platform for research in compilation and virtual machine technologies. We had three main goals in designing the system. First and foremost, we wanted the system to be flexible. We are interested in a variety of compiler and virtual machine research topics, and we wanted a system that would not be specific to researching a particular area.
For example, we have interest in both static and dynamic compilation techniques, and in both type-safe and unsafe languages. We wanted a system that would be as open and general as possible, without sacrificing usability or performance.
Second, we wanted the system to be easy to experiment with. As its primary focus is research, it should be straightforward to prototype new ideas in the framework. With this in mind, we tried to make the system as modular as possible, so that each component is easily replaceable. Learning from our experience with Jalapeno, another virtual machine written in Java, we decided to implement the entire system in Java.
This makes it easy to quickly implement and prototype new ideas, and features like garbage collection and exception tracebacks ease debugging and improve productivity. Java, being a dynamic language, is also a good consumer for many of our dynamic compilation techniques; the fact that our dynamic compiler can compile the code of the virtual machine itself means that it can dynamically optimize the virtual machine code with respect to the application that is running on it. Javas object-oriented nature also facilitates modularity of the design and implementation.
Third, we wanted the system to be useful to a wide audience. The fact that the system is written in Java means that much of the system can be used on any platform that has an implementation of a Java virtual machine. The fact that Joeq supports popular input languages like Java, C, C++, Fortran, and even x86 binary code increases the scope of input programs. We released the system on the SourceForge web site as open source under the Library GNU Public License.
It has been picked up by researchers on five continents for various purposes, among them: automatic extraction of component interfaces, static whole-program pointer analysis, context-sensitive call graph construction, automatic distributed computation, versioned type systems for operating systems, sophisticated profiling of applications, advanced dynamic compilation techniques, system checkpointing, anomaly detection, secure execution platforms and autonomous systems. In addition, Joeq is now used as the basis of the Advanced Compilation Techniques class taught at Stanford University.
Joeq supports two modes of operation: native execution and hosted execution. In native execution, the Joeq code runs directly on the hardware. It uses its own run-time routines, thread package, garbage collector, etc. In hosted execution, the Joeq code runs on top of another virtual machine. Operations to access objects are translated into calls into the reflection library of the host virtual machine.
The user code that executes is identical, and only a small amount of functionality involving unsafe operations is not available when running in hosted execution mode. Hosted execution is useful for debugging purposes and when the underlying machine architecture is not yet directly supported by Joeq. We also use hosted execution mode to bootstrap the system and perform checkpointing, a technique for optimizing application startup times.
Joeq system consists of seven major parts:
- Front-end: Handles the loading and parsing of input files, such as Java class files, SUIF files, and binary object files.
- Compiler: A framework for performing analyses and optimizations on code. This includes the intermediate representation (IR) of our compiler.
- Back-end: Converts the compilers intermediate representation into native, executable code. This code can be output to an object file or written into memory to be executed. In addition, it generates metadata about the generated code, such as garbage collection maps and exception handling information.
- Interpreter: Directly interprets the various forms of compiler intermediate representations.
- Memory Manager: Organizes and manages memory. Joeq supports both explicitly-managed and garbage-collected memory.
- Dynamic: Provides profile data to the code analysis and optimization component, makes compilation policy decisions, and drives the dynamic compiler.
- Run-time Support: Provides runtime support for introspection, thread scheduling, synchronization, exception handling, interfacing to external code, and language-specific features such as dynamic type checking.

This is a project to create 64-bit virtual CPU, create a 64 bit assembler for the CPU and then port C to it, and then create scripts to port GNU/Linux to it.
The aim is to run 64-bit Linux on common 8/16/32 bit CPUs in applications where speed is not an issue.
Enhancements:
- Added C code intended tor a PIC Preliminary documentation More updates to Gambas program

Waimea is a fast and highly customizable virtual multiple desktop window manager. It supports advanced features like transparent textures and Xft fonts.

The Kernel-Machine Library is a freely available (released under the GPL) C++ library to promote the use and progress of kernel machines. It is both for academic use and for developing real world applications.
The Kernel-Machine Library draws heavily from features of modern C++ such as template meta-programming to achieve high performance while at the same time offering a comfortable interface.
It enables compile-time selection of specialised algorithms on the basis of data types: for example, the specific case of a SVM in combination with a linear kernel can be computed by a specialised efficient algorithm.
The Kernel-Machine Library has implementations for the following kernel machines and their cited algorithms:
- Support Vector Machine [1, 2, 3]
- Relevance Vector Machine [4]
- Kernel Recursive Least Squares [5]
- Adaptive Sparseness using Jeffreys Prior [6]
- Smooth Relevance Vector Machine [7]
Up till now, the focus has been on regression. The handling of classification and ranking problems is being added.

Jolt is a Java Virtual Machine Daemon. This program provides a means to invoke the JDK tools javac, javadoc, and jar from the command line while reusing the same JVM instance across invocations.

Jolt daemon is intended primarily for use as a helper tool to make compilation of Java code with make as fast as (and potentially faster than) with Jakarta Ant.

It can also be used to run arbitrary Java programs (as with java); this is particularly useful for command-line utilities that are run over and over, where the cost of launching the JVM each time would be prohibitive (or at the very least, annoying).

Usage:

The `runjolt shell script can be used as a wrapper for the `jolt binary. It checks for the presence of the JAVA_HOME environment variable (which should be set to the top-level installation directory of JDK 1.4.0 or later) and augments LD_LIBRARY_PATH accordingly before invoking `jolt proper.