An Improved Flash-Based Swap System for Performance and Flash Endurance
Jungseung Lee, Huijin Park, Yongchun Song · 2023 IEEE International Conference on Consumer Electronics (ICCE) · 2023
Recently, CE devices are increasingly supporting various features that meet user requirements, and accordingly, the demand for the amount of memory required continues to increase. Compression swap technology, which stores compressed data in memory, is widely used as a solution to secure free memory, but fundamentally, compressed data occupies the memory. On the other hand, the traditional disk swap method using disk as a swap device has the advantage of not requiring memory occupancy, but in an embedded environment, it has been difficult to be widely used due to the overall system performance degradation due to disk I/O operation and the lifespan limit of flash as a disk device. In this work, we present a method to minimize the overhead caused by I/O by screening swap data to be stored in flash as a way to solve the performance and life limitations that have hindered the use of flash swap. At the same time, it shows how to asynchronously writeback the swap data and how to utilize the enhanced mode of flash to overcome the flash lifespan limit. As a result of the evaluation, our scheme shows performance degradation of less than 5 % on average in the DTV user scenario compared to the existing compression swap technology in a DTV environment using total 1.5GB memory, while free memory improves by more than 130MB in idle time.