We use a grid engine software behind the scenes to dispatch tests to dozens of hosts and CPUs. This means that to total linear time of a build can be 3 days, but because it is done in parallel, the wall time is actually much smaller, e.g. 16 hours.

Jenkins cannot know that we are doing this, but nevertheless, the timeline has all the information to report it correctly, but it does not.

In the attached picture, we can clearly see that the duration was approximately 16 hours in the text, but Jenkins extends the red "line" to over 3 days.