Real-time scheduling for Java']Java

Composition methods and tools are generally focusing on producing components integrating different functionality and aspects, and neglect the dynamical issues very often. In the case of dynamic deployment of distributed components, a new component is added to the running system by starting the component on a remote node. This paper describes authors' efforts to compose an application using dynamically connected components (tasks to be migrated with real-time constraints). For migrating the components from one host to the other, a Java agent environment was used. The drawbacks of the off-the-self Java scheduling software products verified the need o implementing a standard JVM-based real-time schedu er. Authors have created a high-level solution that does not need special virtual machine features different from those in the language specification. This paper details the requirements and constraints, specifies the scheduler architecture, scheduling strategies at id algorithm. Evaluation of the implemented scheduling strategies - earliest deadline first, least laxity first, and rate monotonic - shows that the EDF is the most efficient alternative.