Simon Willison’s Weblog

30th January 2009 - Link Blog

All you ever wanted to know about writing bloom filters. This helped me understand a key use case for bloom filters: reducing the impact of the “worst case search is when there are no matching results so everything gets scanned” problem.

Posted 30th January 2009 at 8:26 am

Recent articles

Claude Opus 5.5, GPT-6 Sol, GPT-6 Luna, and a new price war - 22nd September 2026
Jev introduces a new shape of LLM - System One, aka Decision Models - 21st September 2026
Generating running routes with GPT-6 Astra and ChatGPT Work - 12th September 2026

This is a link post by Simon Willison, posted on 30th January 2009.

bloom-filters 5 jonathan-ellis 2 search 94

Monthly briefing

Sponsor me for $10/month and get a curated email digest of the month's most important LLM developments.

Pay me to send you less!

Sponsor & subscribe