Improving the Forward Progress of Transient Systems

Emerging applications for Internet of Things (IoT) devices demand smaller mass, size, and cost whilst increasing capability reliability. Energy harvesting can provide power to these ultra-constrained devices, but introduces unreliability, unpredictability, intermittency. Schemes wireless sensors without batteries or supercapacitors overcome intermittency through saving system state into nonvolatile memory before the supply drops below minimum operating voltage, termed transient, intermittent computing. However, this significant time energy overheads. This article presents two schemes that significantly reduce overheads: entering a sleep mode avoid utilizing direct access (DMA) when saves are required. Time previously wasted on instead be used perform useful computation, “forward progress.” We practically validate proposed approaches across range sources IoT benchmarks demonstrate up 46.8% 40.3% increase in forward progress 91.1% 85.6% reduction overheads each scheme, respectively.