namedthreads

Patch to propagate Python thread names to system thread names


Keywords
debugging, python, python-3, threading
License
BSD-3-Clause
Install
pip install namedthreads==1.0

Documentation

namedthreads

This is a hack to propagate thread names set in Python to the system.

WARNING: This is only meant for testing/debugging purposes. Do NOT run in production.

The problem

You can name threads in Python like so:

import threading

my_thread = threading.Thread(target=my_func, name="my-thread")

But when running ps, top and similar, you'll notice that the thread name isn't visible in these tools, making threading bugs somewhat harder to debug.

The solution

A comment in bpo-15500 lines out a monkeypatch that uses ctypes to set the name using libpthread.pthread_setname_np. While this works beautifully, it hasn't been included in core python due to compatibility reasons. This module packages the monkeypatch in an easy to install package.

Before After

Usage

Install

pip install namedthreads

Manual patching

Run this as early as possible in your code:

import namedthreads
namedthreads.patch()

Automatic patching

Inspired by Graham Dumpleton's autowrapt, this module can be activated automatically. Due to the hacky nature of this approach, it is guarded by checking the presence of an environment variable, NAMEDTHREADS. Automatic patching is only activated if this environment variable is set

NAMEDTHREADS=1 python myscript.py