[issue10348] multiprocessing: use SysV semaphores on FreeBSD

Jesse Noller added the comment: Charles and Antoine's votes match my own, therefore closing the bug wont fix -- resolution: -> wont fix status: open -> closed ___ Python tracker __

[issue10348] multiprocessing: use SysV semaphores on FreeBSD

Antoine Pitrou added the comment: Agreed with Charles-François. -- nosy: +pitrou ___ Python tracker ___ ___ Python-bugs-list mailing

[issue10348] multiprocessing: use SysV semaphores on FreeBSD

Charles-François Natali added the comment: -1 IMHO, implementing SysV semaphores would be a step backwards, plus the API is a real pain. I think there's no reason to complicate the code to accomodate such corner cases, especially since the systems that don't support POSIX semaphores will even

[issue10348] multiprocessing: use SysV semaphores on FreeBSD

STINNER Victor added the comment: Martin fixed test_concurrent_futures (#10798), this issue can be implemented later. -- type: -> feature request versions: +Python 3.3 -Python 3.2 ___ Python tracker

[issue10348] multiprocessing: use SysV semaphores on FreeBSD

STINNER Victor added the comment: OpenBSD. According to Martin, OpenBSD doesn't implement POSIX semaphores. --- I don't have an installation of OpenBSD, but... In FreeBSD, POSIX semaphores are implemented in sys/kern/uipc_sem.c. In http://www.openbsd.org/cgi-bin/cvsweb/src/sys/kern/ that fil

[issue10348] multiprocessing: use SysV semaphores on FreeBSD

STINNER Victor added the comment: Darwin (Mac OS X). According to the following email (July 2010), Darwin supports POSIX semaphores and the default limit is 10,000 semaphores. http://osdir.com/ml/darwin-dev/2010-07/msg00012.html The limit is configurable via sysctl as kern.posix.sem.max. ---

[issue10348] multiprocessing: use SysV semaphores on FreeBSD

STINNER Victor added the comment: NetBSD. Extract of the sem_close() manpage http://www.daemon-systems.org/man/sem_close.3.html --- STANDARDS The sem_open(), sem_close(), and sem_unlink() functions conform to ISO/IEC 9945-1:1996 (``POSIX.1''). HISTORY Support for named semaphore

[issue10348] multiprocessing: use SysV semaphores on FreeBSD

STINNER Victor added the comment: More info about FreeBSD. "sysctl p1003_1b.sem_nsems_max" gives the maximum number of POSIX semaphores (per process? system wide?). Since FreeBSD 8.1, "sudo sysctl -w p1003_1b.sem_nsems_max=256" can be used to change this limit at runtime. Before FreeBSD 8.1

[issue10348] multiprocessing: use SysV semaphores on FreeBSD

Jesse Noller added the comment: Adding, or moving, to SYSV semaphores is very low on the list of things to do. If someone were to provide a patch, I'm sure we could consider it. -- ___ Python tracker

[issue10348] multiprocessing: use SysV semaphores on FreeBSD

STINNER Victor added the comment: See also http://semanchuk.com/philip/sysv_ipc/: "System V IPC for Python - Semaphores, Shared Memory and Message Queues" -- ___ Python tracker ___

[issue10348] multiprocessing: use SysV semaphores on FreeBSD

STINNER Victor added the comment: See also #5725. -- ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe: http://ma

[issue10348] multiprocessing: use SysV semaphores on FreeBSD

STINNER Victor added the comment: Examples of programs using SysV semaphores: http://firebird.cvs.sourceforge.net/viewvc/firebird/firebird2/src/jrd/isc_sync.cpp?revision=HEAD&view=markup (Firebird, search "#ifdef USE_SYS5SEMAPHORE" sections) https://github.com/mono/mono/blob/master/mono/io-lay

[issue10348] multiprocessing: use SysV semaphores on FreeBSD

STINNER Victor added the comment: Informations about SysV semaphores: - functions: semget(), semop(), semctl(), ftok() - http://perldoc.perl.org/IPC/SysV.html - http://beej.us/guide/bgipc/output/html/multipage/semaphores.html -- ___ Python tracker

[issue10348] multiprocessing: use SysV semaphores on FreeBSD

Changes by Antoine Pitrou : -- nosy: +asksol ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python

[issue10348] multiprocessing: use SysV semaphores on FreeBSD

STINNER Victor added the comment: It looks like SysV semaphores are also preferred on Darwin. So I suppose that Mac OS X would also benefit of this issue. Maybe also other OSes (Solaris?). See also issue #7272. -- nosy: +jnoller title: multiprocessing: use SYSV semaphores on FreeBSD -

[issue10348] multiprocessing: use SYSV semaphores on FreeBSD

New submission from STINNER Victor : Support POSIX semaphore on FreeBSD is recent, optional (eg. disabled by default in FreeBSD 7) and limited (30 semaphores). SYSV should be used instead because they are less limited or more adjustable (at runtime: POSIX semaphore requires to recompile the ke