CPU Utilization

I’m really confused about the “CPU Utilization” chart which is shown on the test result page since I found different interpretations of this chat in this forum:

  1. Some posts in this forum state that this is chart shows client side (browser) CPU utilization caused by javascript execution etc…:


  1. Other posts claim this this chart shows CPU utilization on the server:


Which of these interpretations is true? From my personal experience would opt for the second option since CPU Utilization varies a lot depending on test location.

Can someone please clearify?