How can they estimate this? What about all the libraries that might not be compatible with the solution PyPy comes up with?
This feels like a number that might in the end blow up to 10x the original estimate.
This feels like a number that might in the end blow up to 10x the original estimate.
(And really, was it intended to be dangerous in this way?)
No, these libraries are already semantically broken in the same way e.g. libraries which didn't properly close their files and assumed the CPython refcounting GC would wipe there asses were broken.
They're already broken under two non-GIL'd implementations.
Expecting bad code to magically work forever is unrealistic and hinders progress.
What python doesn't have is a C api for extensions that makes sense without a GIL. So ideally a correct threadsafe C extension will continue to be correct, which probably implies that a function called "PyEval_AcquireLock" will continue to provide similar guarantees. Which means that the process for utilizing more cores with pure python code in one process will probably be a gradual upgrade process.
It might as well not be the case here, I just found it funny, 50k is our little magic number.