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by mrbrowning 4697 days ago
> I think the first thing that should be mentioned in any introductory article on Python threads is that Python threads work great for IO concurrency but they won't help with CPU concurrency. Things like downloading files, sending data over a socket will work nicely.

Python's threads certainly work acceptably for IO-bound purposes, but given the overhead of creating a real OS thread and the potential for GIL thrashing when using Python 2.x on a multicore machine, I'm not sure why you wouldn't favor a greenlet-based solution in most such cases, especially since you don't even really have to drop the threading idiom to do so.
1 comments
rdtsc 4697 days ago
Good point. I use gevent and now switching back to eventlet. But that is a different post perhaps.

Not only do you get more threads with greenlet you also don't have to worry about a whole class of synchronization side-effects since a greenlet will only switch contexts on an IO operation. (Now some might argue that is bad since you could be calling a function and not know what happens in side or what might happen in the future so you should lock anyway).

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mrbrowning 4697 days ago
Out of curiosity, why the switch? I went with gevent pretty early on because it seemed like eventlet had some weird quirks, but I have to admit never really giving it a close look.
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rdtsc 4697 days ago
Because it is supported in older Pythons on some servers I work on. Works with PyPy. It has less dependencies (just greenlet) and easier to build.

gevent also has been thrashing around is it 1.0 beta? Switching to libev or libevent. And eventlet picked up more steam with more test coverage.

So no one big issue just a bunch of small ones.

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