ResCheck: Resilient Checkpointing for Energy Harvesting Systems

Checkpointing is a key technique to guarantee execution correctness and ensure progress forwarding in energy harvesting systems. However, checkpointing itself introduces system overhead due to extra operations of data movements between volatile memory and nonvolatile memory. Moreover, execution rollback to the latest checkpoint under a power failure can cancel some obtained progress and this waste is highly correlated to the latest checkpoint interval. These two kinds of overhead can be quite high if the checkpoint interval setting mismatches the power input characteristic. Unlike previous checkpointing schemes emphasizing on optimizing data copy overhead, this paper further takes into account the characteristic of input power sources and proposes a resilient checkpointing scheme, ResCheck, which can capture the power input changes and thus accordingly mitigate checkpoint overhead and rollback cost. The proposed ResCheck, directed by a lightweight neural network-based power level predictor, is capable of adjusting the checkpoint intervals to fit different power levels at runtime. In this way, an energy harvesting system equipped with ResCheck can achieve both fewer checkpoint number and lower execution rollback punishment. Our experimental results show that ResCheck can reduce an average checkpoint number of 24.4% and 14.6% over the conventional periodic checkpointing scheme and the state-of-the-art iCheck scheme respectively. Meanwhile, ResCheck improves average performance as well as energy efficiency by more than three times compared to iCheck.