[issue20353] Hanging bug with multiprocessing + sqlite3 + tkinter (OS X 10.9 only)

Change by Terry J. Reedy : -- resolution: -> out of date stage: -> resolved status: open -> closed ___ Python tracker ___ ___

[issue20353] Hanging bug with multiprocessing + sqlite3 + tkinter (OS X 10.9 only)

Terry J. Reedy added the comment: hang.py uses the default multiprocessing start method, which was then 'fork'. It is now 'spawn' on macOS. And there have been many other changes. When I run the following from IDLE, it finishes immediately. import multiprocessing, sqlite3 def hang():

[issue20353] Hanging bug with multiprocessing + sqlite3 + tkinter (OS X 10.9 only)

Change by Erlend Egeberg Aasland : -- nosy: +erlendaasland ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe:

[issue20353] Hanging bug with multiprocessing + sqlite3 + tkinter (OS X 10.9 only)

Terry J. Reedy added the comment: #33111 claims that importing tkinter is enough to hang multiprocessing on MacOS up through 3.6. -- components: +macOS nosy: +ronaldoussoren, terry.reedy ___ Python tracker

[issue20353] Hanging bug with multiprocessing + sqlite3 + tkinter (OS X 10.9 only)

Change by Eitan Adler : -- nosy: +eadler ___ Python tracker ___ ___ Python-bugs-list

[issue20353] Hanging bug with multiprocessing + sqlite3 + tkinter (OS X 10.9 only)

Evan Jones added the comment: I believe the root cause of this bug is the following issue: http://bugs.python.org/issue27126 ; a workaround is to run the following code before forking any subprocesses: sqlite3.connect(':memory:').close() -- nosy: +evan.jo...@bluecore.com

[issue20353] Hanging bug with multiprocessing + sqlite3 + tkinter (OS X 10.9 only)

Ned Deily added the comment: Arnon, what version of sqlite3 is the Python linked with? Try: python3.4 -c import sqlite3;print(sqlite3.sqlite_version) What kind of database access is happening in your program, i.e. strictly multi-read, one writer many reads, multiple-writers? Also, regarding

[issue20353] Hanging bug with multiprocessing + sqlite3 + tkinter (OS X 10.9 only)

Arnon Sela added the comment: I ran into similar issue on OSX. Multiprocessing system where processes issue sqlite3.connect(). Periodically it hangs. System is using Python 3.4.3 and sqlite3; it doesn't use tkinter Noticed the following: 1. This doesn't happen on Ubuntu 2. It happens even

[issue20353] Hanging bug with multiprocessing + sqlite3 + tkinter (OS X 10.9 only)

New submission from Craig Silverstein: Don't ask me how, but our code managed to combine multiprocessing, sqlite, and tkinter all in one app, and got a hanging behavior, though only on a particular OS. Removing any of these removes the hang. I filed this under tkinter, but the fault could

[issue20353] Hanging bug with multiprocessing + sqlite3 + tkinter (OS X 10.9 only)

Ned Deily added the comment: I can reproduce a hang (but not a crash) when using a Python 2.7.x or 3.4.x built from source and linking with the OS X 10.9 system libsqlite3. Using the Apple-supplied Python 2.7 on 10.9 causes a crash in libdispatch. Using Python 2.7.6 or 3.4.0 from the

[issue20353] Hanging bug with multiprocessing + sqlite3 + tkinter (OS X 10.9 only)

Craig Silverstein added the comment: Thanks -- we managed to work around it by removing the tkinter dependency, so this isn't time-critical for us. It is curious, though. One thing I forgot to mention before is that playing around with the hung process in gdb, it seems like sqlite was

[issue20353] Hanging bug with multiprocessing + sqlite3 + tkinter (OS X 10.9 only)

Changes by Ben Alpert spicyjalap...@gmail.com: -- nosy: +spicyj ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue20353 ___ ___ Python-bugs-list