Interconnect-Aware Coherence Protocols for Chip Multiprocessors

Improvements in semiconductor technology have made it possible to include multiple processor cores on a single die. Chip Multi-Processors (CMP) are an attractive choice for future billion transistor architectures due to their low design complexity, high clock frequency, and high throughput. In a typical CMP architecture, the L2 cache is shared by multiple cores and data coherence is maintained among private L1s. Coherence operations entail frequent communication over global on-chip wires. In future technologies, communication between different L1s will have a significant impact on overall processor performance and power consumption. On-chip wires can be designed to have different latency, bandwidth, and energy properties. Likewise, coherence protocol messages have different latency and bandwidth needs. We propose an interconnect composed of wires with varying latency, bandwidth, and energy characteristics, and advocate intelligently mapping coherence operations to the appropriate wir...

• Type: Conference
• Year: 2006
• Where: ISCA
• Authors: Liqun Cheng, Naveen Muralimanohar, Karthik Ramani, Rajeev Balasubramonian, John B. Carter
• Keywords: Coherence Operations, Coherence Protocols, Hardware, ISCA 2006, On-chip Wires