Scroll to navigation

relbench(8) John relbench(8)


relbench - John the Ripper benchmark output comparison tool




relbench is a Perl script to compare two "john --test" benchmark runs, such as for different machines, "make" targets, C compilers, optimization options, or/and versions of John the Ripper.

To use it, redirect the output of each "john --test" run to a file, then run the script on the two files.

Most values output by the script indicate relative performance seen on the second benchmark run as compared to the first one, with the value of 1.0 indicating no change, values higher than 1.0 indicating speedup, and values lower than 1.0 indicating slowdown. Specifically, the script outputs the minimum, maximum, median, and geometric mean for the speedup (or slowdown) seen across the many individual benchmarks that "john --test" performs.

It also outputs the median absolute deviation (relative to the median) and geometric standard deviation (relative to the geometric mean). Of these two, a median absolute deviation of 0.0 would indicate that no deviation from the median is prevalent, whereas a geometric standard deviation of 1.0 would indicate that all benchmarks were sped up or slowed down by the exact same ratio or their speed remained unchanged.

In practice, these values will tend to deviate from 0.0 and 1.0, respectively.


File containing benchmark results from the first test run via john --test.
File containing benchmark results from the second test run via john --test.




John the Ripper password cracker is free and Open Source software. Copyright (c) 2011 by Solar Designer.

This manual page was written by Lars Vogdt for the openSUSE operating system (but it may be freely used, modified, and redistributed by others).

October 2013 Lars Vogdt