Fixed #27685 -- Added watchman support to the autoreloader.

Removed support for pyinotify (refs #9722).

3 files changed, 31 insertions, 6 deletions

diff --git a/docs/internals/contributing/writing-code/unit-tests.txt b/docs/internals/contributing/writing-code/unit-tests.txt
index c3af1cd02f..3480e3f2ca 100644
--- a/docs/internals/contributing/writing-code/unit-tests.txt
+++ b/docs/internals/contributing/writing-code/unit-tests.txt
@@ -229,6 +229,7 @@ dependencies:
 *  Pillow_
 *  PyYAML_
 *  pytz_ (required)
+*  pywatchman_
 *  setuptools_
 *  memcached_, plus a :ref:`supported Python binding <memcached>`
 *  gettext_ (:ref:`gettext_on_windows`)
@@ -258,6 +259,9 @@ and install the Geospatial libraries</ref/contrib/gis/install/index>`.
 Each of these dependencies is optional. If you're missing any of them, the
 associated tests will be skipped.
 
+To run some of the autoreload tests, you'll need to install the Watchman_
+service.
+
 .. _argon2-cffi: https://pypi.org/project/argon2_cffi/
 .. _bcrypt: https://pypi.org/project/bcrypt/
 .. _docutils: https://pypi.org/project/docutils/
@@ -267,12 +271,14 @@ associated tests will be skipped.
 .. _Pillow: https://pypi.org/project/Pillow/
 .. _PyYAML: https://pyyaml.org/wiki/PyYAML
 .. _pytz: https://pypi.org/project/pytz/
+.. _pywatchman: https://pypi.org/project/pywatchman/
 .. _setuptools: https://pypi.org/project/setuptools/
 .. _memcached: https://memcached.org/
 .. _gettext: https://www.gnu.org/software/gettext/manual/gettext.html
 .. _selenium: https://pypi.org/project/selenium/
 .. _sqlparse: https://pypi.org/project/sqlparse/
 .. _pip requirements files: https://pip.pypa.io/en/latest/user_guide/#requirements-files
+.. _Watchman: https://facebook.github.io/watchman/
 
 Code coverage
 -------------
diff --git a/docs/ref/django-admin.txt b/docs/ref/django-admin.txt
index e8371897e2..22a5c4dbac 100644
--- a/docs/ref/django-admin.txt
+++ b/docs/ref/django-admin.txt
@@ -879,13 +879,26 @@ needed. You don't need to restart the server for code changes to take effect.
 However, some actions like adding files don't trigger a restart, so you'll
 have to restart the server in these cases.
 
-If you are using Linux and install `pyinotify`_, kernel signals will be used to
-autoreload the server (rather than polling file modification timestamps each
-second). This offers better scaling to large projects, reduction in response
-time to code modification, more robust change detection, and battery usage
-reduction.
+If you're using Linux or MacOS and install both `pywatchman`_ and the
+`Watchman`_ service, kernel signals will be used to autoreload the server
+(rather than polling file modification timestamps each second). This offers
+better performance on large projects, reduced response time after code changes,
+more robust change detection, and a reduction in power usage.
 
-.. _pyinotify: https://pypi.org/project/pyinotify/
+.. admonition:: Large directories with many files may cause performance issues
+
+    When using Watchman with a project that includes large non-Python
+    directories like ``node_modules``, it's advisable to ignore this directory
+    for optimal performance. See the `watchman documentation`_ for information
+    on how to do this.
+
+.. _Watchman: https://facebook.github.io/watchman/
+.. _pywatchman: https://pypi.org/project/pywatchman/
+.. _watchman documentation: https://facebook.github.io/watchman/docs/config.html#ignore_dirs
+
+.. versionchanged:: 2.2
+
+   Watchman support replaced support for `pyinotify`.
 
 When you start the server, and each time you change Python code while the
 server is running, the system check framework will check your entire Django
diff --git a/docs/releases/2.2.txt b/docs/releases/2.2.txt
index 45d436ebe1..13f7617888 100644
--- a/docs/releases/2.2.txt
+++ b/docs/releases/2.2.txt
@@ -203,6 +203,10 @@ Management Commands
   comments in generated migration file(s). This option is also available for
   :djadmin:`squashmigrations`.
 
+* :djadmin:`runserver` can now use `Watchman
+  <https://facebook.github.io/watchman/>`_ to improve the performance of
+  watching a large number of files for changes.
+
 Migrations
 ~~~~~~~~~~
 
@@ -487,6 +491,8 @@ Miscellaneous
   :func:`~django.contrib.sitemaps.ping_google` function, set the new
   ``sitemap_uses_https`` argument to ``False``.
 
+* :djadmin:`runserver` no longer supports `pyinotify` (replaced by Watchman).
+
 .. _deprecated-features-2.2:
 
 Features deprecated in 2.2