I once spent ages trying to determine why a Python unit test that sorted timestamps constantly failed on Windows. In the test, we compared the timestamps of per

I once spent ages trying to determine why a Python unit test that sorted timestamps constantly failed on Windows. In the test, we compared the timestamps of performed operations, and checked to confirm that the operations happened in sequence based on their timestamp (I'm sure many of you see where this is going). On Windows, the timestamp for all the actions was exactly the same, so when sorted, the actions appeared out-of-order. It was then that I discovered Python's time library on Windows only reports times with a resolution of ~1ms, whereas on Linux the same code reports times with a resolution of ~10us. That one was actually super fun to track down, but super disappointing to discover it's not something that's easily remedied. (For those about to suggest how it should have been done, the application also stored an atomic revision counter, so the unit test was switched to that instead of a timestamp.)