Linus Torvalds Wrote Linux Kernel Patches With Claude Code, Sees 3x Speedup

Linus Torvalds used Anthropic's Claude Code to develop eight experimental Linux kernel patches that speed up page cache reads. On his laptop with an Intel Core i7-8565U, throughput rose from about 10 million to 30–33 million reads per second with eight threads. The patches are not merged into mainline and carry caveats.

• 8 patches on Linux 7.3-rc6 change page cache reads via RCU without folio references
• 8 threads: from ~10M to 30–33M reads/s; 4 threads: from 9–12M to 25–26M
• Single-thread test: from ~8M to nearly 9M reads per second
• Claude Code produced code, tests and draft text; Torvalds ran the benchmarks himself