Compare-perf: CLI tool for simple benchmarking with statistics

The tool gives more meaningful statistics about test runs during benchmarking, e.g. by running two commands and seeing which performs better.

Here is some example output (taken from the slides linked to in the article):

  +------------------------------------------------------------------------------+
  |                   +                            x                             |
  |                   +                            x                             |
  |           +       +                            x x            x              |
  | +    ++   +++     +                            x xxx xx       x              |
  |++ ++++++++++++++++++                   x  x    x xxx xxx  xxxxx              |
  |++ ++++++++++++++++++ +++ +       ++   xxxxxxxxxx xxxxxxxxxxxxxxxx  xx x    xx|
  |     |______MA______|                        |________A________|              |
  +------------------------------------------------------------------------------+
      N           Min           Max        Median           Avg        Stddev
  x  57      45.62364     46.437353      45.93506     45.951554    0.19060973
  +  57     44.785579     45.534727     45.042576     45.056702    0.16634531
  Difference at 95.0% confidence
    -0.894852 +/- 0.0656777
    -1.94738% +/- 0.142928%
    (Student's t, pooled s = 0.178889)