PEP-703 contains a whore Motivation section. Long enough to require a summary: > Python’s global interpreter lock makes it difficult to use modern multi-core C

PEP-703 contains a whore Motivation section. Long enough to require a summary: > Python’s global interpreter lock makes it difficult to use modern multi-core CPUs efficiently for many scientific and numeric computing applications. Heinrich Kuttler, Manuel Kroiss, and Paweł Jurgielewicz found that multi-threaded implementations in Python did not scale well for their tasks and that using multiple processes was not a suitable alternative. > The scaling bottlenecks are not solely in core numeric tasks. Both Zachary DeVito and Paweł Jurgielewicz described challenges with coordination and communication in Python. > Olivier Grisel, Ralf Gommers, and Zachary DeVito described how current workarounds for the GIL are “complex to maintain” and cause “lower developer productivity.” The GIL makes it more difficult to develop and maintain scientific and numeric computing libraries as well leading to library designs that are more difficult to use.