A crosstalk aware interconnect with variable cycle transmission

Crosstalk between wires, caused by increased capacitive coupling, is considered one of the major factors that affect the performance of interconnects such as buses. The data-dependent nature of crosstalk-induced delays necessitates bus cycle time to be designed for the worst case crosstalk. However, this pessimism incurs a significant performance penalty. Consequently, we propose a crosstalk aware interconnect that uses a faster clock and dynamically controls the number of cycles required for transmission based on the estimated delay of the data pattern to be transmitted. In order to accomplish this, we designed a crosstalk analyzer circuit that is incorporated into the sender side of the bus and support a variable cycle transmission mechanism. We evaluate the effectiveness of the proposed scheme focusing on the on-chip buses of a microprocessor and by using the SPEC2000 benchmarks. The experimental results show that the proposed approach improves performance by 31.5% as compared to the original pessimistic approach. Furthermore, we employ a coding optimization to enhance the effectiveness of the proposed approach. We also show that the proposed scheme is an area-efficient approach to improving performance as compared to other crosstalk reduction schemes.