The Time-constrained Barrier Synchronizer and its Applications in Parallel Systems

A barrier synchronizer, allowing processors to participate dynamically by letting them register their intent to participate within a timeout period, is presented. The synchronizer allows some applications - like software combining and highly concurrent queue operations - to be implemented in a rather unconventional but highly efficient manner. The barrier synchronizer generates successive time windows, allowing requests within the same window to be combined, thus ensuring a more-or-less fixed latency for the Fetch-and-Op primitive.