HalftimeHash: Modern Hashing without 64-bit Multipliers or Finite Fields

TL;DR

HalftimeHash is a high-performance hashing algorithm for long strings that reduces collisions and increases speed without relying on 64-bit multipliers or finite field arithmetic, improving portability and efficiency.

Contribution

It introduces a novel hashing method that outperforms existing algorithms in collision reduction and speed, avoiding hardware-dependent operations.

Findings

Over 50% performance increase compared to existing hash functions

Lower collision probability than universal hash functions

No use of 64-bit multipliers or finite field arithmetic

Abstract

HalftimeHash is a new algorithm for hashing long strings. The goals are few collisions (different inputs that produce identical output hash values) and high performance. Compared to the fastest universal hash functions on long strings (clhash and UMASH) HalftimeHash decreases collision probability while also increasing performance by over 50%, exceeding 16 bytes per cycle. In addition, HalftimeHash does not use any widening 64-bit multiplications or any finite field arithmetic that could limit its portability.