Python multiprocessing for CPU-bound tasks

🚀 Advanced Python Tips #6 — multiprocessing.Pool “Python is slow.” No. Your execution model might be. A for loop in Python is optimized in C and is surprisingly efficient. The real limitation isn’t iteration speed; it’s synchronous execution. If you're running CPU-bound tasks sequentially, you're leaving multiple CPU cores idle. Here’s the uncomfortable truth many developers gloss over: 👉 The GIL prevents true parallelism with threads for CPU-bound workloads. 👉 multiprocessing, however, does not share the GIL across processes. If your tasks are CPU-intensive and independent, multiprocessing.Pool enables real parallelism. With Pool:  - Each process has its own Python interpreter  - Each process has its own GIL  - Work is distributed across multiple CPU cores  - You get true parallel execution But here’s the part that rarely makes it into tutorials: ⚠️ multiprocessing has non-trivial overhead (process spawn + pickling) ⚠️ For lightweight tasks, it can be slower than a simple for loop ⚠️ For I/O-bound workloads, asyncio or threading may be more efficient Multiprocessing isn’t a magic performance switch. It’s a tool, and it only shines in the right context. It makes sense when your workload is:  - CPU-bound  - Independent  - Heavy enough to amortize process overhead Otherwise, you’re just parallelizing the wrong bottleneck. Python isn’t slow. Misapplied parallelism is. Do you analyze whether your bottleneck is CPU-bound or I/O-bound before parallelizing?

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