Section: Software and Platforms

ProActive

Participants : Françoise Baude, Denis Caromel, Ludovic Henrio, Fabrice Huet [correspondant] , Bastien Sauvan.

ProActive (Proactive Parallel Suite ) is a Java library (Source code under AGPL license) for parallel, distributed, and concurrent computing, also featuring mobility and security in a uniform framework. With a reduced set of simple primitives, ProActive provides a comprehensive API to simplify the programming of applications that are distributed on a Local Area Network (LAN), on cluster of workstations, Clouds, or on Internet Grids.

The library is based on an Active Object pattern that is a uniform way to encapsulate:

• a remotely accessible object,

• a thread,

• an actor with its own script,

• a server of incoming requests,

• a mobile and potentially secure agent.

and has an architecture to inter-operate with (de facto) standards such as Web Service, HTTP transport, ssh, Globus, etc.

ProActive is only made of standard Java classes, and requires no changes to the Java Virtual Machine, no preprocessing or compiler modification; programmers write standard Java code. Based on a simple Meta-Object Protocol, the library is itself extensible, making the system open for adaptations and optimisations. ProActive currently uses the RMI Java standard library as default portable transport layer, but others such as Ibis or HTTP can be used instead, in an adaptive way.

ProActive is particularly well-adapted for the development of applications distributed over the Internet, thanks to reuse of sequential code, through polymorphism, automatic future-based synchronisations, migration of activities from one virtual machine to another. The underlying programming model is thus innovative compared to, for instance, the well established MPI programming model.

In order to cope with the requirements of large-scale distributed and heterogeneous systems like the Grid, many features have been incorporated into ProActive, including support for many transport and job submission protocols, GCM component support, graphical visualization interface, object migration, distributed and non-functional exception handling, fault-tolerance and checkpointing mechanisms; file transfer capabilities, a job scheduler, a resource manager able to manage various hosting machines, support for JMX and OSGi capabilities, web service object exposition, an SCA personality, etc.

ProActive is a project of the former ObjectWeb, now OW2 Consortium. OW2 is an international consortium fostering the development of open-source middleware for cutting-edge applications: EAI, e-business, clustering, grid computing, managed services and more. For more information, refer to [39] , [37] and to the web pages http://www.objectweb.org and http://proactive.inria.fr/ .

ProActive management, distribution, support, and commercialisation is now ensured by the start-up company ActiveEon (http://www.activeeon.com ), in the context of a collaboration with Inria and UNS.

This year, the OASIS team made the following extensions to the ProActive library:

• Implementations related to the multi-active object programming model: multi-active components, declarative request service priority.

• Extension of the support of non-functional aspects for component systems: scripting language for reconfiguration, interceptor components.