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Preforks interpreters to reduce script startup time

Project Description

Python module launcher

This module tries to improve the start-up time of Python scripts. It
does so by doing two things:

- Eliminating the time it takes to spawn a new Python process.
- Loading modules ahead of time.

Eliminating interpreter start-up time is done by maintaining a pool of
Python processes. Reducing module load times is done by importing
modules immediately after a worker is spawned. Python is smart about
not re-importing modules that are already in ``sys.modules``.

I ended up writing this module because of a few small Qt programs that
weren't launching as fast as I would like them too. The results were a
~100ms reduction in startup time, which can be attributed to PySide
being a hefty package to import.

There are plenty of bugs and todos left - handling return code and
proper process shutdown seem to be on top of the list.



Usage: python-module-launcher-3.3 [-hvdpws] socket [mod, ...]

-h, --help show this help message and exit
-v, --version show version and exit
-d, --daemonize run in background (default: no)
-p, --pidfile pid file to use if running as a daemon
-w, --workers <num> worker processes to start (default: 5)
-s, --spare <num> spare worker processes to maintain (default: 3)

socket path to AF_UNIX socket
mod* modules to pre-import in workers

python-module-launcher-3.3 launcher.sock numpy PySide.QtCore

echo -n "module" | nc -U launcher.sock
echo -n "file path/to/ arg1 arg2 | nc -U launcher.sock
echo -n "entrypoint name==0.1.0 console_scripts name arg1 arg2"

You can send the following commands to the unix socket::

file path/to/ arg1 arg2 ...
module arg1 arg2 ...
entrypoint name==0.1.0 console_scripts name arg1 arg2 ...


This module is released under the terms of the `Revised BSD License`_.

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