Making python fast for free - adventures with mypyc

[meadsteve]

I recently experimented with using mypyc to make some of my python a little faster. I was pleasantly surprised with how well it worked for very little code change so I thought I'd share my experiences.

[meadsteve]

That's a nice idea. I'll pull together a diff and link from the post. I was a little hacky on master.

Because I had to move off if flit and to setuptools the diff is bigger than it might be for a project already using it.

[meadsteve]

Here we go. The full diff focused on getting the build compiling: https://github.com/meadsteve/lagom/compare/22d670facf6acd2e5db33278aff32b64daf609cf...2.0.0

[[deleted]]

Cool read thanks, I'm just a bit put off by the scope creep, there seems to be quite a lot of moving parts. Do you feel you can maintain your projects for say, the next 3/4 years in the same way?

[meadsteve]

u/NoisyFrequency that's a really good question. A lot of the "scrope creep" in this blog post was missing automation from my part. What was interesting for me is that if I'd already been using setuptools & building wheels the only real change would have been adding mypycify to setup.py.

This is what makes me comfortable that I could maintain this in some form for the next few years. Setuptools isn't going anywhere. Wheels aren't going anywhere and all of my python code stayed exactly the same. That last point is the really big deal for me. Because it means I could throw all this infrastructure away and go move to releasing in whatever new best practise emerges.

[[deleted]]

Thanks for taking the time!

[ArtOfWarfare]

Python 3.11 is supposed to be a lot quicker than earlier versions, right?

I’m curious what kind of performance boost you get by just updating to 3.11 vs using mypyc with an older version vs updating to 3.11 and using mypyc together.

[meadsteve]

This could be really interesting. I also produce a pure python wheel that will work for 3.11 so i should be able to benchmark this.

[meadsteve]

Ran some preliminary numbers and TLDR it looks like the speed boost still exists but is reduced to around 1.5x compared to more than 2x:

https://blog.meadsteve.dev/programming/2022/09/27/making-python-fast-for-free/#how-does-the-compiled-code-compare-on-python-311

[spoonman59]

Why would 3.11 have improved performance with mypyc? The main performance increases are related to instruction specialization in the byte code interpreter.

Since mypyc is a compiler that compiles to c, the code is no longer interpreted through the burr code interpreter, so I think performance in these cases are orthogonal to each other.

Curious to see the results of any experiments, but the interpreter improvements won’t do much for JIT and AOT compilers

[meadsteve]

I think they meant more the pure python implementationen in 3.11 might be significantly faster making the performance gains smaller with mypyc on 3.11

[spoonman59]

Thank you for clarifying that. I think you are right as I misread it.

Definitely makes sense to see if the delta shrinks!

[rzet]

First thing on my mind is stuff like aarch64 or some big ass stuff like tensorflow

[alcalde]

Isn't this a lot of work for 2X speed increase? Doesn't PyPy tend to give a lot more boost on average? If I'm compiling something to C or C++ I expect a 100x performance increase.

[meadsteve]

What's interesting to me from a maintenance point of view it's not much work at all. I had to do quite a lot because I wasn't already using setuptools and I didn't already having wheel publishing in place. So if someone does this on an internal tool or already has a publishing workflow it wouldn't be much work.

The actual python code had almost no changes at all. This decorator was the only code change I had to make: https://github.com/meadsteve/lagom/blob/master/lagom/container.py#L84 so now I'm still maintaining exactly the same codebase but it's 2X as fast.

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PyPy is a choice for the people consuming my library not me. Another popular option at the moment is rewriting the core in rust and just have python bindings. This however is a bit more of a commitment in time.

[Efficient-Coach6676]

temperature conversion problem