Apr 29, 2023 · Apr 24, 2023 · Apr 24, 2023 · Apr 24, 2023 · Apr 25, 2023 · Apr 25, 2023
diff --git a/Doc/whatsnew/3.12.rst b/Doc/whatsnew/3.12.rst
  replacement strings containing group references by 2--3 times.
  (Contributed by Serhiy Storchaka in :gh:`91524`.)

 * Speed up :class:`asyncio.Task` creation by deferring expensive string formatting.
  (Contributed by Itamar O in :gh:`103793`.)


 CPython bytecode changes
 ========================
diff --git a/Lib/asyncio/tasks.py b/Lib/asyncio/tasks.py
            raise TypeError(f"a coroutine was expected, got {coro!r}")

        if name is None:
            self._name = f'Task-{_task_name_counter()}'
            # optimization: defer task name formatting to first get_name
            self._name = None
        else:
            self._name = str(name)

        return self._context

    def get_name(self):
        if self._name is None:
            self._name = f'Task-{_task_name_counter()}'
        return self._name

    def set_name(self, value):
diff --git a/Misc/NEWS.d/next/Core and Builtins/2023-04-24-14-38-16.gh-issue-103793.kqoH6Q.rst b/Misc/NEWS.d/next/Core and Builtins/2023-04-24-14-38-16.gh-issue-103793.kqoH6Q.rst
 Optimized asyncio Task creation by deferring expensive string formatting
 (task name generation) from Task creation to the first time ``get_name`` is
 called. This makes asyncio benchmarks up to 5% faster.
diff --git a/Modules/_asynciomodule.c b/Modules/_asynciomodule.c
    Py_XSETREF(self->task_coro, coro);

    if (name == Py_None) {
        name = PyUnicode_FromFormat("Task-%" PRIu64,
                                    ++state->task_name_counter);
        // optimization: defer task name formatting
        // set task_name to None to indicate deferred formatting
        Py_INCREF(name);
    } else if (!PyUnicode_CheckExact(name)) {
        name = PyObject_Str(name);
    } else {
 /*[clinic end generated code: output=0ecf1570c3b37a8f input=a4a6595d12f4f0f8]*/
 {
    if (self->task_name) {
        if (Py_IsNone(self->task_name)) {
            asyncio_state *state = get_asyncio_state_by_def((PyObject *)self);
            PyObject *name = PyUnicode_FromFormat(
                "Task-%" PRIu64, ++state->task_name_counter);
            Py_XSETREF(self->task_name, name);
        }
        return Py_NewRef(self->task_name);
    }
Original file line number	Diff line number	Diff line change
Expand Up		@@ -553,6 +553,9 @@ Optimizations
		replacement strings containing group references by 2--3 times.
		(Contributed by Serhiy Storchaka in :gh:`91524`.)

		* Speed up :class:`asyncio.Task` creation by deferring expensive string formatting.
		(Contributed by Itamar O in :gh:`103793`.)


		CPython bytecode changes
		========================
Expand Down
Original file line number	Diff line number	Diff line change
Expand Up		@@ -104,7 +104,8 @@ def __init__(self, coro, *, loop=None, name=None, context=None):
		raise TypeError(f"a coroutine was expected, got {coro!r}")

		if name is None:
		self._name = f'Task-{_task_name_counter()}'
		# optimization: defer task name formatting to first get_name
		self._name = None
Copy link Member gvanrossumApr 25, 2023 Choose a reason for hiding this comment The reason will be displayed to describe this comment to others.Learn more. Why do we need to optimize the .py version (which is normally not run since there is a C accelerator version)? Copy link ContributorAuthor itamaroApr 25, 2023 Choose a reason for hiding this comment The reason will be displayed to describe this comment to others.Learn more. we definitely don't need to optimize the python version. I assumed we wanted to maintain parity between the versions, but maybe it doesn't matter to this extent (or my assumption was wrong and parity is not a goal). I will revert the changes to the python version. willingc reacted with thumbs up emoji
		else:
		self._name = str(name)

Expand DownExpand Up		@@ -143,6 +144,8 @@ def get_context(self):
		return self._context

		def get_name(self):
		if self._name is None:
		self._name = f'Task-{_task_name_counter()}'
		return self._name

		def set_name(self, value):
Expand Down
Original file line number	Diff line number	Diff line change
		@@ -0,0 +1,3 @@
		Optimized asyncio Task creation by deferring expensive string formatting
		(task name generation) from Task creation to the first time ``get_name`` is
		called. This makes asyncio benchmarks up to 5% faster.
Original file line number	Diff line number	Diff line change
Expand Up		@@ -2069,8 +2069,9 @@ _asyncio_Task___init___impl(TaskObj self, PyObject coro, PyObject *loop,
		Py_XSETREF(self->task_coro, coro);

		if (name == Py_None) {
		name = PyUnicode_FromFormat("Task-%" PRIu64,
		++state->task_name_counter);
		// optimization: defer task name formatting
		// set task_name to None to indicate deferred formatting
		Py_INCREF(name);
		} else if (!PyUnicode_CheckExact(name)) {
		name = PyObject_Str(name);
		} else {
Expand DownExpand Up		@@ -2449,6 +2450,12 @@ _asyncio_Task_get_name_impl(TaskObj *self)
		/[clinic end generated code: output=0ecf1570c3b37a8f input=a4a6595d12f4f0f8]/
		{
		if (self->task_name) {
		if (Py_IsNone(self->task_name)) {
		asyncio_state state = get_asyncio_state_by_def((PyObject )self);
		PyObject *name = PyUnicode_FromFormat(
		"Task-%" PRIu64, ++state->task_name_counter);
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		Py_XSETREF(self->task_name, name);
		}
		return Py_NewRef(self->task_name);
		}

Expand Down