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

Qwen3-4B-Thinking: "This is art - pelicans don't ride bikes!" - 10th August 2025
My Lethal Trifecta talk at the Bay Area AI Security Meetup - 9th August 2025
The surprise deprecation of GPT-4o for ChatGPT consumers - 8th August 2025

caching 48 http 97 performance 92 varnish 10

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