Hardware Supported Synchronization Primitives for Clusters

Parallel architectures with shared memory are well suited to many applications, provided that efficient shared memory access and process synchronization mechanisms are available. When the parallel machine is a cluster with physically distributed memory, software based synchronization mechanisms together with virtual memory infrastructure can implement Software Distributed Shared Memory (S-DSM), a shared memory abstraction on a distributed memory machine. However, the communication network overload from the emulation can limit the performance of such systems. This problem motivated our research, in which we developed a set of synchronization primitives for S-DSM on reconfigurable hardware. This hardware implements an auxiliary synchronization network, which works in parallel to the data communication network. Experiments evaluating our hardware implementation against a software one showed that our system increases the performance of these S-DSM primitives by a factor of 40 or more.