Avoid python setup time

I just searched for the same and found this:

http://blogs.gnome.org/johan/2007/01/18/introducing-python-launcher/

Python-launcher does not solve the problem directly, but it points into an interesting direction: If you create a small daemon which you can contact via the shell to fork a new instance, you might be able to get rid of your startup time.

For example get the python-launcher and socat¹ and do the following:

PYTHONPATH="../lib.linux-x86_64-2.7/" python python-launcher-daemon &
echo pass > 1
for i in {1..100}; do 
    echo 1 | socat STDIN UNIX-CONNECT:/tmp/python-launcher-daemon.socket & 
done

Todo: Adapt it to your program, remove the GTK stuff. Note the & at the end: Closing the socket connection seems to be slow.

The essential trick is to just create a server which opens a socket. Then it reads all the data from the socket. Once it has the data, it forks like the following:

        pid = os.fork()
        if pid:
            return

        signal.signal(signal.SIGPIPE, signal.SIG_DFL)
        signal.signal(signal.SIGCHLD, signal.SIG_DFL)

        glob = dict(__name__="__main__")
        print 'launching', program
        execfile(program, glob, glob)

        raise SystemExit

Running 100 programs that way took just 0.7 seconds for me.

You might have to switch from forking to just executing the code instead of forking if you want to be really fast.

(That’s what I also do with emacsclient… My emacs takes ~30s to start (due to excessive use of additional libraries I added), but emacsclient -c shows up almost instantly.)

¹: http://www.socat.org

Write the "do this several 100 times" logic in your Python script. Call it ONCE from that other language.

Use timeit instead:

http://docs.python.org/library/timeit.html