ADeS, a simulator for AADL

Introduction

ADeS is a software tool to simulate the behavior of system architectures described with the AADL language. Moreover, the name of this tool means Architecture Description Simulation. This tool makes possible the evaluation and analysis of the behavior of a system during its specification with AADL, for instance by helping in the choice of dimensioning parameters: what will happen if we enlarge an execution time? if we change a deadline? if we bind a task on another processor?

ADeS is an Eclipse plug-in, based on Osate, an AADL modeling plug-in developed by SEI, and on Topcased project. This technical choice ensure an easy installation and a perfect interoperability with other AADL tools.

The first version of ADeS started in 2002 during a joint study with the European Space Agency (ESA) to assess the interest of AADL for the space domaine. The AADL standard was then under development, and this study contributed to stabilise it.

The process of a simulation is divided into several phases:

Lexical analysis, syntactic analysis and semantic analysis of the AADL description: this phase consists in verifying that the description provided as input is correct, and return the possible errors to the user, and then building an internal representation of the architecture which will be used by the following phases. The AADL parser used here directly comes from the Osate plug-in;
Instanciation of the simulation objects: each element of the described architecture is represented by one or more simulation elements which are able to represent the behavior of the AADL element, as described by the standard of the language.
Simulation itself: the simulation elements are activated to simulate the behavior of the architecture. The results are organised and displayed for the user.

Description

Conformance with the standard

The vocation of ADeS is to support the whole behaviors as described by the AADL standard. Its current version, still under development, only implement a subset of these behaviors.

In the future, ADeS will also support the behavior annex, currently developed by the standardisation committee, but not yet stabilised.

Results of the simulation

The whole results of the simulation are recorded into a log file. They may be used afterward for analysis or replay.

Flexibility

ADeS has been designed to provide a high flexibility. It is possible to easily add new policies for scheduling, queuing management, etc. ADeS may also be adapted to simulation of components other than those defined by the AADL standard.

Development process

Current state

ADeS is currently still a prototype tool. The priority for us it to represent as perfectly as possible the whole behaviors, as specified by the AADL standard. Thus, the graphical representation does not show all the underlying results.

ADeS also depends on the capacities of OSATE, the AADL modeling tool on which it is built. Some AADL constructs can not already be instanciated in a satisfying way, as it is for the subprograms.

However, Axlog is ready to adapt its priorities and adapt the developments in order to better tackle more specific needs which would be expressed by final users. If interested, just contact us.

Downloads

ADeS is available for download. For this, please see the download page.

ADeS is now hosted on the GForge site of Topcased: http://gforge.enseeiht.fr/projects/ades.

update 2007-12-04