Free-threaded Python 3.14 hits 65.7 GB/s JSON parsing on 64 threads

Daniel Lemire benchmarked the free-threaded Python 3.14 (python3.14t) without the GIL, achieving 65.7 GB/s JSON parsing throughput with a SIMD JSON library across 64 threads.

2026-10-12 ~ 2026-10-13 · 2 related posts

• Free-threaded Python 3.14t plus fastsimd parses JSON at 65.7 GB/s on 64 cores — lemire · 2026-10-12
• Parsing JSON at tens of GB/s in Python: free-threaded 3.14 hits 65.7 GB/s on 64 cores — charliermarsh · 2026-10-13