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BSML is a library for parallel programming with the functional language Objective Caml. It is based on an extension of the λcalculus by parallel operations on a parallel data structure named parallel vector. The execution time can be estimated, dead-locks and indeterminism are avoided. Programs are written as usual functional programs (in Objective Caml) but using a small set of additional functions. Provided functions are used to access the parameters of the parallel machine and to create and operate on parallel vectors. It follows the execution and cost model of the Bulk Synchronous Parallel model. The paper presents the lastest implementation of this library and experiments of performance prediction.

bsp is a bridging model between abstract execution and concrete parallel systems. Structure and abstraction brought by bsp allow to have portable parallel programs with scalable performance predictions, without dealing with low-level details of architectures. In the past, we designed bsml for programming bsp algorithms in ml. However, the simplicity of the bsp model does not fit the complexity of today's hierarchical architectures such as clusters of machines with multiple multi-core processors. The multi-bsp model is an extension of the bsp model which brings a tree-based view of nested components of hierarchical architectures. To program multi-bsp algorithms in ml, we propose the multi-ml language as an extension of bsml where a specific kind of recursion is used to go through a hierarchy of computing nodes. We define a formal semantics of the language and present preliminary experiments which show performance improvements with respect to bsml.

International audienceBulk Synchronous Parallel ML is a high-level language for programming parallel algorithms. Building upon OCaml and using the BSP model, it provides a safe setting for their implementation, avoiding concurrency related problems (deadlocks, indeterminism). Only a limited set of the features of OCaml can be used in BSML to respect its safety: this paper describes a way to add exception handling to this set by extending and adapting OCaml's exceptions. The behaviour of these new exceptions and the syntactic constructs to handle them, together with their implementation, are described in detail, and results over an example are given

This paper presents a Bulk-Synchronous Parallel (BSP) algorithm to compute the discrete state space of structured models of security protocols. The BSP model of parallelism avoids concurrency related problems (mainly deadlocks and non-determinism) and allows us to design an efficient algorithm that is at the same time simple to express. A prototype implementation has been developed, allowing to run benchmarks showing the benefits of our algorithm.