How to obtain a Thread id in Python?

python

threading

logging

debugging

byAlex Kataev·Feb 19, 2025

To get the ID of a thread in Python, use threading.get_native_id() for the current thread or choose t.native_id for a specific Thread object t.

import threading

# One ring to rule the current thread
current_thread_id = threading.get_native_id()

# A thread's gotta have name, right?
t = threading.Thread(target=lambda: None)
t.start()
specific_thread_id = t.native_id

Debugging and Monitoring? Thread ID to the Rescue

When you need to debug or monitor multithreaded apps, knowing the ID of your Threads is super handy. For instance, in those puzzled moments of 'Which thread was that again?' while logging multithreaded messages.

The good news? Python's got you covered. Retrieve thread id without passing extra parameters. A real time-saver, right?

Ins & Outs of Thread Attributes

The threading module is your one-stop shop for thread-related attributes:

threading.get_ident(): Obtain the 'thread identifier', a unique integer for the current thread.
threading.current_thread().ident: Similar to get_ident(), but for any Thread instance.
threading.current_thread().name: Gets the name of the current thread. It's like a name tag for your logs!

Remember: a Thread's ident and name attributes are like its driver's license. Have it handy!

Version-Specific and System-Specific Methods

Introduced in Python 3.8, threading.get_native_id() provides an OS-level thread identifier. For older versions, you'll need threading.get_ident() or threading.current_thread().ident.

System-specific needs, say in Linux, may require the Linux thread id. Combine syscall(SYS_gettid) with the ctypes library, and Voila! Just a heads up: this involves advanced, system-dependent coding. Tread lightly!

Automatic Logging of Thread IDs

Logging and thread IDs, an unbeatable duo! The logging module lets you conveniently track threads right in your logs.

import logging

# Configuring log-omatic 5000 (basically Batman's utility belt for logging)
logging.basicConfig(
    level=logging.DEBUG,
    format='%(asctime)s:%(levelname)s:%(thread)d:%(message)s'
)

# Log messages right in the action
def task():
    logging.debug('Logging mode: Thread detective!')

threading.Thread(target=task).start()

Now, your log records will sport thread IDs, making it easier to solve the mysteries of multithreading!

Use Cases and Caveats: Thread IDs in Action

Incorporating thread IDs into your codebase? Take note:

Logging: Tracking thread IDs makes logging from multiple threads a piece of cake.
Debugging: Finding which thread caused an exception just got easier.
Performance monitoring: Thread IDs help tune performance by mapping with system/application metrics.
Caveat: Remember, Thread IDs are no James Bonds. They aren't suitable for security-sensitive purposes. Once a thread exits, IDs may be recycled. Reuse, Reduce, Recycle, right?