2 Open Questions

Should there be a subinterpreter "Serial Execution Mode"?

The idea is to introduce a mode in which using a subinterpreter is less perilous. This mode could be optional for subinterpreters (at the C level), though it's probably not worth it.

• disallow threading
• disallow forking
• eliminate the GIL within each subinterpreter
• start the subinterpreter in its own thread (and pin it there)
• (maybe) add mode management

What is the "main" thread of a subinterpreter?

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