← 💻 Coding & Engineering Craft
Core
Concurrency and the GIL
Concurrency screens punish people who reach for threads without knowing what Python's GIL does. The GIL means threads do not run Python bytecode in parallel, so threads help I/O-bound work and do nothing for CPU-bound work, which needs processes. The other half is correctness: shared mutable state needs a lock, and a bounded queue is the clean way to hand work between producers and consumers without races.
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RELATED CONCEPTS
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