[BangPypers] Ideas for Python concurrency...

[Noufal Ibrahim]

On Tue, Feb 08 2011, vikas ruhil wrote:

> i am telling about that specific case for that project , also specific
> about question which is ask by Vishal . i know OS always matter but
> not in some specific case i know you talking about this
> "multiprocessing is a package that supports spawning processes using
> an API similar to the threading
> <http://docs.python.org/library/threading.html#module-threading>module.

I know the difference between the threading and multiprocessing
modules. 

> The multiprocessing package offers both local and remote concurrency,
> effectively side-stepping the *Global Interpreter
> Lock*<http://docs.python.org/glossary.html#term-global-interpreter-lock>by
> using subprocesses instead of threads. Due to this, the
> multiprocessing module allows the programmer to fully leverage
> multiple processors on a given machine. It runs on both Unix and
> Windows."

Yes but it comes with it's own disadvantages. It still doesn't solve the
problem of effective multi*threading*. CPU bound threads are still
forcefully serialised by the GIL. If you use processes instead of
threads, you won't face the problem but you'll use processed which are
more heavyweight than threads. 

> Noufal everything what they is not correct you can visit here with
> expectation of python documentation  OK i go through with this type problem
> with on all  type that's why i am saying they update very later okay z .
> check there are two link one of unix , another for Linux may these for are
> appropriate python for using  mutiprocessing.
> http://archive.debian.net/sarge/allpackages?format=txt.gz*
> *
>
> *http://www.freebsd.org/cgi/man.cgi?query=sem_open&apropos=0&sektion=0&manpath=FreeBSD+6.3-RELEASE&format=html)*

I'm not sure how these links are relevant to this whole discussion. I'm
also a little unsure about the point you're trying to make. The
difference between Windows and Linux is mentioned here by Jesse (the
original author and maintainer of multiprocessing)

http://stackoverflow.com/questions/765129/hows-python-multiprocessing-implemented-on-windows/765207#765207

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