On-chip sensor networks for soft-error tolerant real-time multiprocessor systems-on-chip

As transistor density continues to increase with the advent of nanotechnology, reliability issues raised by the more frequent appearance of soft errors are becoming critical for future embedded multiprocessor systems design. State-of-the-art techniques for soft error protections targeting multiprocessor systems result either high chip cost and area overhead or high performance degradation and energy consumption, and do not fulfill the increasing requirements for high performance and dependability. In this article we present a systematic approach, that is, the Sensor Networks-on-Chip (SENoC), to collaboratively and efficiently manage on-chip applications and overcome reliability threats to Multiprocessor Systems-on-Chip (MPSoC). A hardware-software collaborative approach is proposed to solve soft error problems: a hardware-based on-chip sensor network is built for soft error detection, and a software-based recovery mechanism is applied for soft error correction. A two-step scheduling scheme is presented for reliable application and chip management, combining an off-line static optimization stage for application performance maximization and an online lightweight dynamic adjustment stage to handle runtime variations and exceptions. This strategy introduces only trivial overhead on hardware design and much lower overhead on software control and execution, and hence performance degradation and energy consumption is greatly reduced. We build a cycle-accurate simulator using SystemC, and verify the effectiveness of our technique by comparing performance with related techniques on several real-world applications.