This project develops an existing scalable fault-tolerant and visually programmable platform called GLU which enables parallel application to be run on existing hardware. The essential property of GLU that makes it all work is the way it actually combines declarative and procedural code. GLU programs consist of a declarative top layer and lower layers of procedural code, e.g., C or FORTRAN. The procedural code is written without thinking about parallel evaluation. All the parallelism and the fault tolerance come from the declarative level. GLU will be developed by making improvements at various levels: in the range of machines that can be used, in performance (and measurement thereof), in the declarative/procedural interface to allow systematic reuse of existing code, in the graphical specification of the declarative layer, and in the graphical layer itself.
