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
Idle enter / exit frequencies were selected to always add up to 180 hertz and also to avoid going below 25 hertz and avoid known alias frequencies.
This gave: 6 processes at 30 hz; 5 processes at 36 hz; 4 processes at 45 hz; 3 processes at 60 hz; 2 processes at 90 hz; and 1 process at 180 hz.
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 number of processes changes.
The raw data for this experiment is no longer available.
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.
Note: the slight roll off at high load and 5 and 6 processes, is an issue with the actual load being less than expected. There is a fix for the main program, for future experiments. As a background task reported load averages were over sampled throughout this experiment, and was used to fix the graphs.
An overview of all of the reported load average background samples:
Detail A: Lookup the correct Reported Load Average for an actual 6 processes load of about 5.6
Detail B: Lookup the correct Reported Load Averages for the upper end of the 5 processes data set
The corrected graph, replaces the above graph in the parent web page:
