SuperNet: Multimode interconnect architecture for manycore chIPs

Designers of the on-chIP interconnect for manycore chIPs are faced with the dilemma of meeting performance, power and reliability requirements for different operational scenarios. In this paper, we propose a multimode on-chIP interconnect called SuperNet. This interconnect can be configured to run in three different modes: energy efficient mode; performance mode; and, reliability mode. Our proposed interconnect is based on two parallel multi-vt optimized packet switched network-on-chIP (NoC) meshes. We describe the circuit design techniques and architectural modifications required to realize such a multimode interconnect. Our evaluation with diverse set of applications show that the energy efficient mode can save on average 40% NoC power, whereas the performance mode can improve the core IPC by up to 13% on selected high MPKI applications. The reliability mode provides protection against soft errors in the router's data path through byte oriented SECDED codes that can correct up to 8 bit errors and detect up to 16 bit errors in a 64 bit flit, whereas the router's control path is protected through DMR lock step execution.