[hurin]

>Python developers would almost all upgrade in a single minute for 30%+ better performance.

But strangely they don't - PyPy has hardly gained traction (albeit the python2->python3 switch didn't help) and looking at the benchmarks that's more like 5-7x performance.

I suspect that most often, in places where performance matters enough in a way that would warranted refactoring a code-base from cpython to PyPy, they already rewrote the botte-neck parts in C anyways.

[xioxox]

A lot of the problem is that PyPy isn't completely compatible with C extensions.

[danieloaks]

I want to use PyPy, and I have used it for a biggish server-based project I've been a part of.

The issue I've usually had with it is just small things – maybe an module we depend on doesn't work with PyPy yet, maybe PyPy3 isn't 3.3-compatible yet and can't use "yield from", which we use in our code or which our libraries use.

Dealing with those sort of small issues (and/or waiting for PyPy to fix them), worrying about whether the project I'm currently working on can use PyPy or if I need to use CPython instead, etc makes me stop worrying about trying to use it after a while. In my dev environment at least.

I do really love what the PyPy guys are doing though, and when it works it works damn well. Building it from source is also super pretty.

[stock_toaster]

pypy is great (we use it at work for a few services), but it has slow startup/jit warm up, and uses crazy lots of ram. Once it warms up though, it is pretty darn fast (for python).

[vessenes]

I like PyPy, it's great work. But, it doesn't always work. Our last project that used python seriously used tornado and occasionaly numpy. Getting it all glued together was lots and lots of frustration, confusion about versions, and so on. PyPy just isn't mainline python. Which is really what the 2 vs 3 debate is about, in the end. If you have a 'batteries included' language, making breaking changes could take a long time.