Energy Efficiency Enhancement of SCM-based Systems: Write-friendly Coding

With the advent of the Internet of Things (IoT), more and more wearable devices have been developed and integrated into our daily lives. Energy efficiency is critical for these devices because they are typically run on energy-constrained resources like batteries or energy harvesters. The storage-class memory (SCM) technologies and data compression techniques could improve their energy efficiency via reducing data movements and squeezing the data size, respectively, where data compression is especially important for IoT and embedded systems to reduce the volume of data for the space-constrained memory/storage devices. Nevertheless, both of them cannot be aware of their inherent characteristics for further minimization of energy consumption. To this end, a write-friendly coding scheme is proposed in this work that jointly manages both techniques to yield energy-efficient SCM-based systems. Moreover, a novel design of ignorable bits is presented to partially skip write operations after completing data compression without sacrificing data accuracy. We evaluate the proposed scheme via a series of intensive experiments, the experimental results of which indicate that the proposed coding scheme reduces energy consumption by up to 45% under the investigated benchmarks.