Skip to content

bpo-39244: multiprocessing get all start methods #18529

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Closed
idomic wants to merge 17 commits into from
Closed

bpo-39244: multiprocessing get all start methods #18529

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
17 commits
Select commit Hold shift + click to select a range
13c5b05
Hard reset + cherry piciking the changes.
idomic Feb 11, 2020
fdecdf0
📜🤖 Added by blurb_it.
blurb-it[bot] Feb 11, 2020
29d13c9
Added @vstinner News
idomic Feb 12, 2020
135259f
Update Misc/NEWS.d/next/Library/2020-02-11-13-01-38.bpo-38691.oND8Sk.rst
idomic Feb 13, 2020
794b948
Merge branch 'master' of https://github.com/python/cpython
idomic Feb 15, 2020
bfa3cd1
Merge branch 'master' of https://github.com/python/cpython
idomic Feb 16, 2020
71b4de5
Merge branch 'master' of https://github.com/python/cpython
idomic Feb 16, 2020
0c3e3cf
[bpo-39244] multiprocessing.get_all_start_methods() wrong default on …
idomic Feb 16, 2020
4be42f0
Removed residues
idomic Feb 16, 2020
a3fdeb4
Merge branch 'master' into bpo-39244multiprocessing-get_all_start_met…
idomic Feb 16, 2020
23f1b9c
📜🤖 Added by blurb_it.
blurb-it[bot] Feb 16, 2020
b23191c
Merge branch 'bpo-39244multiprocessing-get_all_start_methods' of http…
idomic Feb 16, 2020
ac7ad3f
Removed residues
idomic Feb 16, 2020
f360bec
[bpo-39244] added reviewers comments
idomic Feb 17, 2020
39b8661
[bpo-39244] added reviewers comments
idomic Feb 17, 2020
f303b8f
[bpo-39244] added reviewers comments
idomic Feb 17, 2020
c083041
[bpo-39244] Fixed failing test
idomic Feb 23, 2020
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
2 changes: 2 additions & 0 deletions Lib/multiprocessing/context.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -256,6 +256,8 @@ def get_start_method(self, allow_none=False):
def get_all_start_methods(self):
if sys.platform == 'win32':
return ['spawn']
elif sys.platform == 'darwin':
return ['spawn', 'fork', 'forkserver']

@pppery pppery Feb 17, 2020

Copy link
Copy Markdown

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Is HAVE_SEND_HANDLE guaranteed to be defined on macOS?

@idomic idomic Feb 23, 2020 •
edited
Loading

Copy link
Copy Markdown
Contributor Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I think it's always set from a certain version (could not find documentation for that), the example of the code that defaults to this case and to 'fork' is in the bugs.python.

else:
if reduction.HAVE_SEND_HANDLE:
return ['fork', 'spawn', 'forkserver']
Expand Down
2 changes: 2 additions & 0 deletions Lib/test/_test_multiprocessing.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -4982,6 +4982,8 @@ def test_get_all(self):
methods = multiprocessing.get_all_start_methods()
if sys.platform == 'win32':
self.assertEqual(methods, ['spawn'])
elif sys.platform == 'darwin':
self.assertEqual(methods, ['spawn', 'fork', 'forkserver'])
else:
self.assertTrue(methods == ['fork', 'spawn'] or
methods == ['fork', 'spawn', 'forkserver'])
Expand Down
2 changes: 2 additions & 0 deletions Misc/NEWS.d/next/macOS/2020-02-16-21-24-18.bpo-39244.QGqhjT.rst
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,2 @@
Fixed default :class:`multiprocessing.context` in :func:`get_all_start_methods`
if the context is macOS, return the default 'spawn'