diff options
| -rw-r--r-- | Doc/library/concurrent.futures.rst | 6 | ||||
| -rw-r--r-- | Lib/concurrent/futures/thread.py | 11 | ||||
| -rw-r--r-- | Lib/test/test_concurrent_futures.py | 24 | ||||
| -rw-r--r-- | Misc/NEWS | 3 |
4 files changed, 40 insertions, 4 deletions
diff --git a/Doc/library/concurrent.futures.rst b/Doc/library/concurrent.futures.rst index ae03f4b..d85576b 100644 --- a/Doc/library/concurrent.futures.rst +++ b/Doc/library/concurrent.futures.rst @@ -124,7 +124,7 @@ And:: executor.submit(wait_on_future) -.. class:: ThreadPoolExecutor(max_workers=None) +.. class:: ThreadPoolExecutor(max_workers=None, thread_name_prefix='') An :class:`Executor` subclass that uses a pool of at most *max_workers* threads to execute calls asynchronously. @@ -137,6 +137,10 @@ And:: should be higher than the number of workers for :class:`ProcessPoolExecutor`. + .. versionadded:: 3.6 + The *thread_name_prefix* argument was added to allow users to + control the threading.Thread names for worker threads created by + the pool for easier debugging. .. _threadpoolexecutor-example: diff --git a/Lib/concurrent/futures/thread.py b/Lib/concurrent/futures/thread.py index 3ae442d..6266f38 100644 --- a/Lib/concurrent/futures/thread.py +++ b/Lib/concurrent/futures/thread.py @@ -81,12 +81,13 @@ def _worker(executor_reference, work_queue): _base.LOGGER.critical('Exception in worker', exc_info=True) class ThreadPoolExecutor(_base.Executor): - def __init__(self, max_workers=None): + def __init__(self, max_workers=None, thread_name_prefix=''): """Initializes a new ThreadPoolExecutor instance. Args: max_workers: The maximum number of threads that can be used to execute the given calls. + thread_name_prefix: An optional name prefix to give our threads. """ if max_workers is None: # Use this number because ThreadPoolExecutor is often @@ -100,6 +101,7 @@ class ThreadPoolExecutor(_base.Executor): self._threads = set() self._shutdown = False self._shutdown_lock = threading.Lock() + self._thread_name_prefix = thread_name_prefix def submit(self, fn, *args, **kwargs): with self._shutdown_lock: @@ -121,8 +123,11 @@ class ThreadPoolExecutor(_base.Executor): q.put(None) # TODO(bquinlan): Should avoid creating new threads if there are more # idle threads than items in the work queue. - if len(self._threads) < self._max_workers: - t = threading.Thread(target=_worker, + num_threads = len(self._threads) + if num_threads < self._max_workers: + thread_name = '%s_%d' % (self._thread_name_prefix or self, + num_threads) + t = threading.Thread(name=thread_name, target=_worker, args=(weakref.ref(self, weakref_cb), self._work_queue)) t.daemon = True diff --git a/Lib/test/test_concurrent_futures.py b/Lib/test/test_concurrent_futures.py index cdb9308..46b069c 100644 --- a/Lib/test/test_concurrent_futures.py +++ b/Lib/test/test_concurrent_futures.py @@ -154,6 +154,30 @@ class ThreadPoolShutdownTest(ThreadPoolMixin, ExecutorShutdownTest, unittest.Tes for t in threads: t.join() + def test_thread_names_assigned(self): + executor = futures.ThreadPoolExecutor( + max_workers=5, thread_name_prefix='SpecialPool') + executor.map(abs, range(-5, 5)) + threads = executor._threads + del executor + + for t in threads: + self.assertRegex(t.name, r'^SpecialPool_[0-4]$') + t.join() + + def test_thread_names_default(self): + executor = futures.ThreadPoolExecutor(max_workers=5) + executor.map(abs, range(-5, 5)) + threads = executor._threads + del executor + + for t in threads: + # We don't particularly care what the default name is, just that + # it has a default name implying that it is a ThreadPoolExecutor + # followed by what looks like a thread number. + self.assertRegex(t.name, r'^.*ThreadPoolExecutor.*_[0-4]$') + t.join() + class ProcessPoolShutdownTest(ProcessPoolMixin, ExecutorShutdownTest, unittest.TestCase): def _prime_executor(self): @@ -43,6 +43,9 @@ Core and Builtins Library ------- +- Issue #27664: Add to concurrent.futures.thread.ThreadPoolExecutor() + the ability to specify a thread name prefix. + - Issue #26750: unittest.mock.create_autospec() now works properly for subclasses of property() and other data descriptors. Removes the never publicly used, never documented unittest.mock.DescriptorTypes tuple. |