Do Python webapps require prefork Apache?
Python has a concept known as Global Interpreter Lock (GIL). It means that one Python interpreter process only runs one thread at a time. That's it.
Naturally, webapps tend to use multiple threads to serve multiple requests concurrently (especially if a single request takes some time).
So far, the only Python webapps I've seen used Gunicorn, which uses the old "1 master process, N worker process" prefork approach.
I know Apache supports Python via mod_python and mod_wsgi. Does this mean that Apache+Python requires using the prefork MPM approach?
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In case somebody sees this and cares, that's a sometimes important oversimplification of the GIL. Only one thread can be interpreting Python bytecode at a time. You can absolutely have two threads doing I/O (and a bunch of other things where a single python instruction takes a long time) simultaneously.
youngeng [OP] 1 points · Jun 2024
Interesting, thanks.