您确认您的过程实际上是CPU密集型的，而不是I / O密集​​型？您code看起来很像I / O密集​​型code，这将受益于并行一无所获。

Have you checked that your process is actually CPU-bound and not I/O-bound? Your code looks very much like I/O-bound code, which would gain nothing from parallelization.