This web page provides the details for the data that gives this graph:
The experiment was done on a Ubuntu server 12.04 running a kernel including Commit-ID: c308b56b5398779cd3da0f62ab26b0453494c3d4
Before the commit, every data point in the above graph would be at a reported load average of 0.0
To avoid discontinuities in the reported load averages, and to maintain predictable execution loop times in the main program, the cpu frequency governors were set to powersave mode.
The main program, as a text file.
The program, as a text file, that generates the script for execution conditions of the main program.
The resulting script, as a text file, edited for one hour (4 time constants of the 15 minute load average) of extra settling time between frequencies.
The raw data. (the 180 hertz data was obtained from a previous experiment).
For this experiment the frequencies were selected to be above the known 25 hertz lower limit and away from the known alias frequencies.
The main program parameters and compile time constants were selected to print an update every 10 seconds and to run for 30 minutes.
Obviously, the server can not be used for anything else during the execution of this test, or the reported load averages might be biased.