The "Smart" simulation environment - A tool-set to develop new cache coherency protocols

"Smart" is a new system-level simulation environment that was developed in order to evaluate and improve algorithms for distributed and parallel systems. In this paper we focus our discussion on the developing of new cache coherency mechanisms that were optimized to handle system-level effects such as process switching and task migration. The developing of new cache coherency protocols is a good example to demonstrate many of the important features of Smart, since system-level events have a major influence on the effectiveness of different cache coherency policies and the overall performance of multicache systems. The Smart simulation environment was built as a separate layer that extends existing multi-processing simulators, so we could take the advantage of using mature and reliable simulation engines. Smart also provides a friendly graphical user interface (GUI) that allows: (1) control of different system parameters and mechanisms such as the cache coherency protocol type, cache organization, scheduling policies of processes and threads, etc., (2) simulation of the execution of shared-memory parallel architecture and measuring different systems' performance parameters and (3) use as a powerful visual based debugging tool. Although this paper presents a version of Smart which is dedicated for shared-bus architectures, other libraries of the tool can simulate different parallel and distributed architectures as well.