A microkernel design for component-based parallel numerical software systems

What is the minimal software infrastructure and what type of conventions are needed to simplify development of sophisticated parallel numerical application codes using a variety of software components that are not necessarily available as source code? We propose an opaque object-based model where the objects are dynamically loadable from the le system or network. The microkernel required to manage such a system needs to include, at most a few basic services, namely, { a mechanism for loading objects at run time via dynamic link libraries, and { consistent schemes for error handling and memory management; and selected methods that all objects share, to deal with { object life (destruction, reference counting, relationships), and { object observation (viewing, proling, tracing). We are experimenting with these ideas in the context of extensible numerical software within the ALICE (Advanced Large-scale Integrated Computational Environment) project, where we are building the microkernel to manage the interoperability among various tools for large-scale scientic simulations. This paper presents some preliminary observations and conclusions from our work with microkernel design.