PIRL 2020 Lock free Concurrent Level Hashing for Persistent Memory

This presentation from the PIRL 2020 conference is by Zhangyu Chen of he Huazhong University of Science and Technology. We propose clevel hashing, a lock-free concurrent level hashing, to deliver high performance with crash consistency for persistent memory. In the clevel hashing, we design a multi-level structure for concurrent resizing and queries. Resizing operations are performed by background threads without blocking concurrent queries. For concurrency control, atomic primitives are leveraged to enable lock-free search/insertion/update/deletion. We further propose context-aware schemes to guarantee the correctness of interleaved queries. Our evaluation results show the efficiency of clevel hashing.