Controlling concurrent access to objects in the Raven system

The paper presents the rationale and design of the concurrency control features of Raven, an object-oriented distributed and parallel programming language and system. Raven´s parallel constructs support coarse grained parallelism and are designed to permit programmers to use parallelism with relative ease. To achieve this Raven provides automatic concurrency control on an object´s instance data at method invocation time. Raven allows multiple execution threads to access an object strictly for reading or a single execution thread to access an object for the updating of instance data. Raven is operational on a variety of machine architectures, including a shared memory multiprocessor. Experience indicates Raven´s concurrency support simplifies the task of converting sequential code to run in a parallel or distributed environment