DIALOG — A dataflow model for parallel execution of logic programs

The paper presents a dataflow execution model, DIALOG, for logic programs which operates on an intermediate virtual machine. The virtual machine is granulated at clause argument level to exploit argument parallelism through unification. The model utilises a new variable binding scheme that eliminates dereference operations for accessing variables, and therefore supports OR-parallelism in the highly distributed dataflow environment. The model has been implemented in Occam. A conventional dataflow architecture in support of the model has been simulated as a testbed for the evaluation. The simulation indicates some encouraging results and suggests future improvements.