The State of Python Profiling in 2026

Austin's maintainer surveys Python profiling as CPython 3.15 adds Tachyon (profiling.sampling) to the standard library, built on 3.14's remote-debugging interface. Tachyon only profiles 3.15 and later, whereas py-spy lacks free-threaded support and Scalene profiles from inside the process. Austin 4.1 adds native-stack mode and asyncio task tracking. The author's own CI benchmark, on Linux x86_64 with Python 3.13, shows repeated-stack detection lifting the maximum sampling rate from 121,000 to 166,000 samples/s; the figure comes from the author and wasn't independently checked, and the gain varies with workload.