Simon Willison’s Weblog

High-end Varnish-tuning. Tuning the Varnish HTTP cache to serve 27K requests/second on a single core 2.2GHz Opteron.

Posted 20th October 2009 at 9:25 am

Recent articles

What happens if AI labs train for pelicans riding bicycles? - 13th November 2025
Reverse engineering Codex CLI to get GPT-5-Codex-Mini to draw me a pelican - 9th November 2025
Video + notes on upgrading a Datasette plugin for the latest 1.0 alpha, with help from uv and OpenAI Codex CLI - 6th November 2025

caching 48 http 98 performance 93 varnish 14

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