Exploiting Locality in Scalable Ordered Maps

Abstract

This paper presents the skip vector, a novel high-performance concurrent data structure based on the skip list. Traversal is sped up by flattening the layers of the skip list into vectors, avoiding much of the costly pointer chasing that skip lists incur. The skip vector utilizes optimistic traversal with sequence locks, and hazard pointers for fast, memory-safe, concurrent access. In microbenchmark evaluation, we show that the skip vector offers excellent performance across a range of key ranges, thread counts, and operation mixes. CCS CONCEPTS • Computing methodologies → Concurrent algorithms.