Data Criticality in Multithreaded Applications: An Insight for Many-Core Systems

Multithreaded applications are capable of exploiting the full potential of many-core systems. However, network-on-chip (NoC)-based intercore communication in many-core systems is responsible for 60%-75% of the miss latency experienced by multithreaded applications. Delay in the arrival of critical data at the requesting core severely hampers performance. This brief presents some interesting insights about how critical data are requested from the memory by multithreaded applications. Then it investigates the cause of delay in NoC and how it affects the performance. Finally, this brief shows how NoC-aware memory access optimizations can significantly improve performance. Our experimental evaluation considers Early Restart memory access optimization and demonstrates that by exploiting available NoC resources, critical data can be prioritized to reduce miss penalty by 11% and improve overall system performance by 9%.