English

ExaLogLog: Space-Efficient and Practical Approximate Distinct Counting up to the Exa-Scale

Data Structures and Algorithms 2025-02-28 v2 Databases

Abstract

This work introduces ExaLogLog, a new data structure for approximate distinct counting, which has the same practical properties as the popular HyperLogLog algorithm. It is commutative, idempotent, mergeable, reducible, has a constant-time insert operation, and supports distinct counts up to the exa-scale. At the same time, as theoretically derived and experimentally verified, it requires 43% less space to achieve the same estimation error.

Keywords

Cite

@article{arxiv.2402.13726,
  title  = {ExaLogLog: Space-Efficient and Practical Approximate Distinct Counting up to the Exa-Scale},
  author = {Otmar Ertl},
  journal= {arXiv preprint arXiv:2402.13726},
  year   = {2025}
}

Comments

14 pages, accepted at EDBT 2025

R2 v1 2026-06-28T14:55:38.800Z