Range Queries in Non-blocking $k$-ary Search Trees

TL;DR

This paper introduces a linearizable, non-blocking k-ary search tree supporting fast searches and range queries, tolerating crash failures, and outperforming existing algorithms in small-range query workloads.

Contribution

It presents a novel non-blocking k-ary search tree using single-word CAS that supports linearizable range queries and crash failures, with improved performance.

Findings

Outperforms other algorithms for small-range queries

Rivals the performance of leading concurrent skip-lists

Supports crash failures and linearizable operations

Abstract

We present a linearizable, non-blocking $k$-ary search tree ($k$-ST) that supports fast searches and range queries. Our algorithm uses single-word compare-and-swap (CAS) operations, and tolerates any number of crash failures. Performance experiments show that, for workloads containing small range queries, our $k$-ST significantly outperforms other algorithms which support these operations, and rivals the performance of a leading concurrent skip-list, which provides range queries that cannot always be linearized.