A Fast, Minimal Memory, Consistent Hash Algorithm

TL;DR

This paper introduces jump consistent hash, a simple, fast, and memory-efficient algorithm for evenly distributing keys among buckets, with improved performance over previous methods, suitable mainly for data storage applications.

Contribution

The paper presents jump consistent hash, a novel algorithm that is faster, requires no storage, and provides better load balancing compared to prior consistent hashing methods.

Findings

Requires no storage and is faster than previous algorithms

Provides more even key distribution among buckets

Suitable mainly for data storage applications

Abstract

We present jump consistent hash, a fast, minimal memory, consistent hash algorithm that can be expressed in about 5 lines of code. In comparison to the algorithm of Karger et al., jump consistent hash requires no storage, is faster, and does a better job of evenly dividing the key space among the buckets and of evenly dividing the workload when the number of buckets changes. Its main limitation is that the buckets must be numbered sequentially, which makes it more suitable for data storage applications than for distributed web caching.