AERO-VM Documents

DASIA'03, Prague

Abstract

The AERO (Architecture for Enhanced Reprogrammability and Operability) is an ESA project with the objectives to investigate on a real-time Java virtual machine for ERC32 processor. Special attention was put on the garbage collection mechanism and deterministic execution model. The project have first investigate existing virtual machine to choose a potential candidate that will be customized, are then investigates the definition of requirements concerning a real-time interpreter in on-board systems. The second phase of the project was dedicated to the definition of software functions of the real-time Java virtual machine and to their implementation and assessment through validation tests. The resulting application is the AERO-VM.

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AERO Project documents:

ESTEC 15750/02/NL/LVH

Abstract

This document gives an analysis of the application of Software Java VMs for real time and safety critical space applications. VMs are evaluated by their real time and safety critical features, by their qualitiy, their performance, the Java language and API they support and the expected complexity of the development.

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ESTEC 15750/02/NL/LVH

Abstract

This document presents the modifications and add-ons made to the JamaicaVM virtual machine during the AERO project that result in the JamaicaVM/AERO-VM. The AERO-VM was based on the JamaicaVM and extended by features to be compliant with the requirements of the space domain. In an validation process, the AERO-VM was validated and evaluated to verify that it is compliant with these requirements. The major enhancements made on the basis JamaicaVM are in two areas: First, support for execution on an VxWorks/ERC32 environment via a target specific layer for this environment. Second, support for standard APIs as required in the space domain. Particularly, a subset of the Java standard libraries plus an implementation of a subset of the Real-Time Specification for Java (RTSJ) classes. During the project, enhancements were also made within the framework of the EC IST-funded HIDOORS project . This projet contributed significantly to the RTSJ support within AERO-VM.

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ESTEC 15750/02/NL/LVH

Abstract

This document presents the design and prototype implementation of the static garbage collector in the AERO-VM. The static garbage collector analyzes a program and makes it possible to either insert explicit deallocation instructions are allocate objects on the stack. This releaves the runtime garbage collector of work. Thus, performance is increased. More important is that the predictability of the memory usage increases, since it becomes explicit where memory can be reclaimed. In the general case, a runtime garbage collector is still needed. However, many applications can be implemented so that they can execute with no runtime garbage collector at all.

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ESTEC 15750/02/NL/LVH

Abstract

This document presents the design and prototype implementation of the static garbage collector in the AERO-VM. The static garbage collector analyzes a program and makes it possible to either insert explicit deallocation instructions are allocate objects on the stack. This releaves the runtime garbage collector of work. Thus, performance is increased. More important is that the predictability of the memory usage increases, since it becomes explicit where memory can be reclaimed. In the general case, a runtime garbage collector is still needed. However, many applications can be implemented so that they can execute with no runtime garbage collector at all.

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ESTEC 15750/02/NL/LVH

Abstract

This document is the evaluation report of the AERO Real-time Java Virtual Machine project, output of the task 1.b.2. This document provides evaluation results of the AERO-VM, who is a Java Virtual Machine with real-time capacities, for ERC32 processor. This document contains an overview of tests, and results.

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