[Python] Why does my Python script run significantly slower on Windows than on macOS for the...

I'm running a Python script that reads a large CSV file (~500MB), performs some basic data manipulation using pandas, and writes the result back to disk. The code is exactly the same on both systems, but performance is very different:

macOS (MacBook Air M1, 8GB RAM): ~30 seconds

Windows 11 (Intel i7, 16GB RAM, SSD): ~2 minutes+

I’m trying to understand what might be causing this significant slowdown on the Windows machine, especially since the hardware is arguably better.

✅ Verified Python version — Python 3.11.2 installed on both machines.

✅ Checked pandas version — Both using pandas 2.2.2 and numpy is up to date.

✅ Tested file location — The CSV file is stored locally on both machines (not on a network or external drive).

✅ Disabled antivirus — I paused Windows Defender real-time protection in case it was scanning files during runtime.

✅ Ran with admin privileges — No change.

✅ Monitored CPU and memory usage — No bottlenecks observed. CPU usage stays low on Windows, surprisingly.

✅ Tried WSL — Running the same script under WSL (Ubuntu) on the Windows machine reduced the runtime slightly (~1.5 minutes), but still much slower than macOS.

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