Re: Multiple threads

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Date	Thu, 17 Nov 2011 00:55:40 +1100
Subject	Re: Multiple threads
From	Chris Angelico <rosuav@gmail.com>
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On Thu, Nov 17, 2011 at 12:48 AM, Eduardo Oliva <dutche@gmail.com> wrote:
> Hello, I have a py script that reads for all "m2ts" video files and convert them to "mpeg" using ffmpeg with command line.
>
> What I want to do is:
>
>  I need my script to run 2 separated threads, and then when the first has finished, starts the next one....but no more than 2 threads.
>  I know that Semaphores would help with that.
>  But the problem here is to know when the thread has finished its job, to release the semaphore and start another thread.

First off, it's better in CPython (the most popular Python) to use
multiple processes than multiple threads. That aside, what you're
looking at is a pretty common model - a large number of tasks being
served by a pool of workers.

Have a look at the multiprocessing module, specifically Pool:
Version 2: http://docs.python.org/library/multiprocessing.html
Version 3: http://docs.python.org/py3k/library/multiprocessing.html

Should be fairly straightforward.

ChrisA

Thread

Multiple threads Eduardo Oliva <dutche@gmail.com> - 2011-11-16 05:48 -0800
  Re: Multiple threads Chris Angelico <rosuav@gmail.com> - 2011-11-17 00:55 +1100
  Re: Multiple threads Henrik Faber <hfaber@invalid.net> - 2011-11-16 15:07 +0100
  Re: Multiple threads Christian Heimes <lists@cheimes.de> - 2011-11-16 16:01 +0100
  Re: Multiple threads Thomas Rachel <nutznetz-0c1b6768-bfa9-48d5-a470-7603bd3aa915@spamschutz.glglgl.de> - 2011-11-16 17:45 +0100
    Re: Multiple threads Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2011-11-16 16:38 -0800
  Re: Multiple threads Dave Angel <d@davea.name> - 2011-11-16 12:27 -0500
  Re: Multiple threads Michael Hunter <tahoemph@gmail.com> - 2011-11-16 09:55 -0800
  Re: Multiple threads Dave Angel <d@davea.name> - 2011-11-16 13:06 -0500
  Re: Multiple threads Dave Angel <d@davea.name> - 2011-11-16 13:30 -0500
  Re: Multiple threads Miki Tebeka <miki.tebeka@gmail.com> - 2011-11-16 12:50 -0800

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