From 5361ced5a26552f4ff737bea19662100868ed1f7 Mon Sep 17 00:00:00 2001
From: Matt Van Horn <mvanhorn@gmail.com>
Date: Sun, 8 Mar 2026 20:37:16 -0700
Subject: [PATCH] gh-145238: Add native thread ID to logging record attributes

Add a `nativeThreadId` attribute to `LogRecord` that exposes the
OS-native thread ID via `threading.get_native_id()`. This is useful
for correlating log entries with system tools like htop, strace, and
perf that display native thread IDs.

The attribute can be used in format strings as `%(nativeThreadId)d`.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
---
 Doc/library/logging.rst                                     | 6 ++++++
 Lib/logging/__init__.py                                     | 5 +++++
 .../Library/2026-03-08-00-00-00.gh-issue-145238.nThrId.rst  | 3 +++
 3 files changed, 14 insertions(+)
 create mode 100644 Misc/NEWS.d/next/Library/2026-03-08-00-00-00.gh-issue-145238.nThrId.rst

diff --git a/Doc/library/logging.rst b/Doc/library/logging.rst
index aba530844d7177..136fbd7edf6862 100644
--- a/Doc/library/logging.rst
+++ b/Doc/library/logging.rst
@@ -1062,6 +1062,9 @@ the options available to you.
 |                |                         | of the logging call which resulted in the     |
 |                |                         | creation of this record.                      |
 +----------------+-------------------------+-----------------------------------------------+
+| nativeThreadId | ``%(nativeThreadId)d``  | Native thread ID (if available). See          |
+|                |                         | :func:`threading.get_native_id`.              |
++----------------+-------------------------+-----------------------------------------------+
 | thread         | ``%(thread)d``          | Thread ID (if available).                     |
 +----------------+-------------------------+-----------------------------------------------+
 | threadName     | ``%(threadName)s``      | Thread name (if available).                   |
@@ -1075,6 +1078,9 @@ the options available to you.
 .. versionchanged:: 3.12
    *taskName* was added.
 
+.. versionchanged:: 3.15
+   *nativeThreadId* was added.
+
 .. _logger-adapter:
 
 LoggerAdapter Objects
diff --git a/Lib/logging/__init__.py b/Lib/logging/__init__.py
index 39689a57e6ecd6..9f5b5a48b22d26 100644
--- a/Lib/logging/__init__.py
+++ b/Lib/logging/__init__.py
@@ -350,9 +350,14 @@ def __init__(self, name, level, pathname, lineno,
         if logThreads:
             self.thread = threading.get_ident()
             self.threadName = threading.current_thread().name
+            if threading._HAVE_THREAD_NATIVE_ID:
+                self.nativeThreadId = threading.get_native_id()
+            else: # pragma: no cover
+                self.nativeThreadId = None
         else: # pragma: no cover
             self.thread = None
             self.threadName = None
+            self.nativeThreadId = None
         if not logMultiprocessing: # pragma: no cover
             self.processName = None
         else:
diff --git a/Misc/NEWS.d/next/Library/2026-03-08-00-00-00.gh-issue-145238.nThrId.rst b/Misc/NEWS.d/next/Library/2026-03-08-00-00-00.gh-issue-145238.nThrId.rst
new file mode 100644
index 00000000000000..1a712696aebb33
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2026-03-08-00-00-00.gh-issue-145238.nThrId.rst
@@ -0,0 +1,3 @@
+Added ``nativeThreadId`` attribute to :class:`logging.LogRecord`, exposing
+the OS-native thread ID via :func:`threading.get_native_id`. This can be
+used in format strings as ``%(nativeThreadId)d``.