Thread synchronization unit (TSU): A building block for high performance computers

Abstract

The Thread Synchronization Unit (TSU) is a hardware mechanism that provides data-driven thread synchronization and data consistency for multi-threaded architectures built with control-flow (i.e. commodity) microprocessors. The TSU design is based on the Decoupled Data-Driven model of execution. This model decouples the synchronization from the computation portions of a program and allows them to execute asynchronously. At compile time a program is partitioned into a number of threads of variable granularity and the Data-Driven thread synchronization graph is also constructed. The TSU is responsible for maintaining the synchronization graph implicitly, it determines when a thread is ready for execution without interruption and then feeds it to the microprocessor for execution. The TSU-based machines exhibit the tolerance to long memory and communication latencies, of the data-driven model, with very little overhead and also exploits short-term optimal cache placement and replacement policies. © Springer-Verlag Berlin Heidelberg 1997.