PSL-DB: Non-Volatile Memory-optimized LSM-Tree with Skip List

Chanyeol Park, Dongui Kim, Beomseok Nam

http://doi.org/10.5626/JOK.2020.47.7.635

With the release of Intel"s Optane DC Persistent Memory, non-volatile memory, offering higher capacity than DRAM and showing higher performance than SSD and HDD, is in the spotlight as the next generation of storage devices. In this paper, we propose the Persistent Skip List DataBase (PSL-DB), a key-value store system optimized for the Optane DCPM in app-direct mode. PSL-DB uses a byte-addressable skip list that significantly reduces the I/O traffic as it avoids redundant writes. PSL-DB also does not sacrifice write performance for read performance as it does not degrade the write performance via artificial governors. In our experiments using Intel Optane DC Persistent Memory, PSL-DB shows significantly higher query processing throughput than legacy LevelDB that stores SSTables in Optane DC PM.