On the Evaluation of Space-Time Functions

Abstract

The Proto spatial programming language abstracts the distributed execution of programs as evaluation of spacetime functions over dynamically defined subspaces on a manifold. Previously, however, function evaluation has always been defined in terms of a complete inlining of expressions during compilation. This simplified the definition of programs, at the cost of limiting expressiveness and duplicating code in compiled binaries. In this paper, we address these shortcomings, producing a model of in-place function evaluation and analysis of its implications for Proto. We have extended the MIT Proto compiler and ProtoKernel virtual machine to implement this model, and empirically verified the reduction of compiled binary size.

Software engineering for self-organizing systems

“…This review relies heavily on many colleagues who were kind enough to share their observations on the field, and their own work, with us (alphabetically by last name: Bernhard Bauer, Jake Beal, Olivier Buffet, François Charpillet, Jörg Denzinger, Giovanna Di Marzo Serugendo, Regina Frei, Kurt Geihs, Arnaud Glad, Nicolas Höning, Holger Kasinger, Andrea Omicini, Ingo Scholtes, Olivier Simonin, Paul Valckenaers, Mirko Viroli, and Danny Weyns). The authors particularly appreciate the detailed reviews of the field that several respondents contributed (Beal, 2011; Denzinger et al , 2011; Höning, 2011; Scholtes, 2011; Simonin et al , 2011; Valckenaers, 2011; Viroli & Omicini, 2011; Weyns et al , 2011). Even though these reviews are not publicly available, we have borrowed extensively from their ideas and in some cases their wording, and have cited them in order to give appropriate credit.…”

“…Weyns (2010) demonstrates the integration of multiple mechanisms in an industrial application, but such hybrid approaches are the exception rather than the rule. Beal suggests that ‘the composition of phenomena into a larger complex system is rather understudied’ (Beal, 2011), and identifies three areas that must be pursued.…”

“…The imitation of nature that is so common in identifying individual mechanisms for self-organization holds promise here as well, if we shift our focus from the individual organisms or species to the level of the ecosystem (Kephart et al , 1989; Brueckner, 2000; Janssen, 2002; Viroli & Zambonelli, 2010; Beal, 2011; SAPERE, 2011). In natural ecosystems, individual organisms interact in different ways, including amensalism, competition, antagonism, commensalism, and competition.…”

“…Traditional software engineering assumes that noise (i.e. errors) can be eliminated, while other disciplines recognize that it is unavoidable and seek to damp it or provide for graceful degradation (Beal & Knight Jr, 2008; Beal, 2011). Another example is the adaptation of methods for safety engineering to increasing the robustness and dependability of self-organizing software (Di Marzo Serugendo, 2009).…”

“…Finally, engineers of self-organizing systems can take advantage of recent advances in iterative and incremental development (Larman & Basili, 2003; Beal, 2011). It is impossible to anticipate in advance the states accessible to a self-organizing system as it evolves in an open environment.…”