Use multiprocessing start_method "spawn"
#4305
Closed
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Quoting from https://docs.python.org/3/library/multiprocessing.html#contexts-and-start-methods * fork ... Note that safely forking a multithreaded process is problematic. Available on Unix only. The default on Unix. The idea to try `"spawn"` is the result of deadlock debugging. After reviewing tracebacks @jbms wrote: > This actually looks like a general fork thread-safety issues, not related to pybind11 > Using fork in a multithreaded program is generally not safe
|
Works! That's one way to get rid of the deadlocks (hoping this will do the trick). But I'll try "forkserver", too, in another PR. |
rwgk
pushed a commit
to rwgk/pybind11
that referenced
this pull request
Nov 1, 2022
Alternative to PR pybind#4305
This was referenced Nov 1, 2022
…similar to pybind#4306, the only difference between the two PRs is the `"spawn"` vs `"forkserver"` argument).
rwgk
pushed a commit
to rwgk/pybind11
that referenced
this pull request
Nov 23, 2022
Alternative to PR pybind#4305
rwgk
pushed a commit
that referenced
this pull request
Nov 23, 2022
* Use `multiprocessing` `start_method` `"forkserver"` Alternative to PR #4305 * Add link to comment under PR #4105 * Unconditionally `pytest.skip("DEADLOCK")` for PyPy Windows * Remove `SKIP_IF_DEADLOCK` entirely, for simplicity. Hopefully this PR will resolve the deadlocks for good. * Add "In a nutshell" comment, in response to request by @EricCousineau-TRI
|
This PR was made obsolete by #4306. |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Description
Quoting from
https://docs.python.org/3/library/multiprocessing.html#contexts-and-start-methods
fork
... Note that safely forking a multithreaded process is problematic.
Available on Unix only. The default on Unix.
The idea to try
"spawn"is the result of deadlock debugging. After reviewing tracebacks @jbms wrote:Suggested changelog entry: