Discussion

The Optimization Ladder

Ralfp: CPython 3.13 went further with an experimental copy-and-patch JIT compiler -- a lightweight JIT that stitches together pre-compiled machine code templates instead of generating code from scratch. It's not a full optimizing JIT like V8's TurboFan or a tracing JIT like PyPy's; Good news. Python 3.15 adapts Pypy tracing approach to JIT and there are real performance gains now:https://github.com/python/cpython/issues/139109https://doesjitgobrrr.com/?goals=5,10

josalhor: While this is great, I expected faster CPython to eventually culminate into what YJIT for Ruby is. I'm not sure the current approaches they are trying will get the ecosystem there.

__mharrison__: Great writeup.I've been in the pandas (and now polars world) for the past 15 years. Staying in the sandbox gets most folks good enough performance. (That's why Python is the language of data science and ML).I generally teach my clients to reach for numba first. Potentially lots of bang for little buck.One overlooked area in the article is running on GPUs. Some numpy and pandas (and polars) code can get a big speedup by using GPUs (same code with import change).

seanwilson: > The real story is that Python is designed to be maximally dynamic -- you can monkey-patch methods at runtime, replace builtins, change a class's inheritance chain while instances exist -- and that design makes it fundamentally hard to optimize. ...> 4 bytes of number, 24 bytes of machinery to support dynamism. a + b means: dereference two heap pointers, look up type slots, dispatch to int.__add__, allocate a new PyObject for the result (unless it hits the small-integer cache), update reference counts.Would Python be a lot less useful without being maximally dynamic everywhere? Are there domains/frameworks/packages that benefit from this where this is a good trade-off?I can't think of cases in strong statically typed languages where I've wanted something like monkey patching, and when I see monkey patching elsewhere there's often some reasonable alternative or it only needs to be used very rarely.

LtWorf: I've used a library that patches the zipfile module to add support for zstd compression in zipfiles.In python3.14 the support is there, but 2 years ago you could just import this library and it would just work normally.

kelvinjps10: Great post saved it for when I need to optimize my python code

arlattimore: What a great article!