Slipstream Execution Mode for CMP-Based Multiprocessors

Scalability of applications on distributed sharedmemory (DSM) multiprocessors is limited by communication overheads. At some point, using more processors to increase parallelism yields diminishing returns or even degrades performance. When increasing concurrency is futile, we propose an additional mode of execution, called slipstream mode, that instead enlists extra processors to assist parallel tasks by reducing perceived overheads. We consider DSM multiprocessors built from dualprocessor chip multiprocessor (CMP) nodes with shared L2 cache. A task is allocated on one processor of each CMP node. The other processor of each node executes a reduced version of the same task. The reduced version skips shared-memory stores and synchronization, running ahead of the true task. Even with the skipped operations, the reduced task makes accurate forward progress and generates an accurate reference stream, because branches and addresses depend primarily on private data. Slipstream execution mode...

• Type: Conference
• Year: 2003
• Where: HPCA
• Authors: Khaled Z. Ibrahim, Gregory T. Byrd, Eric Rotenberg
• Keywords: Computer Architecture, HPCA 2003, Slipstream Execution Mode, Slipstream Mode, True Task