Graph Structure Management in Parallel Symbolic Systems

We discuss the efficient exploitation of parallelism in systems where a common data structure is accessed, using message-passing, by a set of parallel processes. In particular, we provide a framework in which such systems can be abstractly represented and present a range of definitions in terms of constraints upon the available parallelism. In addition to considering a particular class of problems (based on common graph structures), we study purely control parallelism. Within these restrictions, we consider applications in automated deduction and garbage collection, and contrast the constraints on parallel activity within such systems. 1 Introduction In this paper we study the general problem of maintaining the integrity of a shared data-structure, which is being manipulated by a set of parallel processes. In particular, we discuss the conflict between maximal exploitation of parallelism and the requirement that the datastructure remain consistent across all its copies. We restrict ou..