Add explicit Numpy import to workaround GIL deadlock with asyncio. #155
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Merging despite failing tests (which are failing due to documentation not passing; need to clean up that flakey CI setup). |
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See #154.
In certain situations (including when using asyncio), Pedalboard's C++ code will implicitly and lazily import NumPy via its Pybind11 bindings. This lazy import can sometimes (!) cause a deadlock on the GIL if multiple threads are attempting it simultaneously. To work around this, we preload Numpy into the current Python process so that Pybind11's lazy import is effectively a no-op.
No tests included here: the buggy behaviour occurs when
numpyisn't loaded into the running Python process, which is very hard to simulate in test without running a subprocess and writing a very elaborate (and likely brittle) test.