Lots of confounds due to non-uniform hardware, etc, but more importantly these are very artificial micro-benchmarks; systems are (ideally) tuned for performance

Lots of confounds due to non-uniform hardware, etc, but more importantly these are very artificial micro-benchmarks; systems are (ideally) tuned for performance on the sorts of loads that they will actually be running under, not artificial tests like "create 65k files of 32B each". In artificial tests like these, you frequently get the best performance by flushing data out as fast as possible, while in most "real-world" scenarios you have some temporal locality that makes keeping data around a win. Optimizing for these sorts of benchmarks can actually harm performance. Still, fun.