3

I noticed that sometime some application are using some impossibly high amount of my CPU according to the Activity Monitor, as the screenshots below illustrate. How comes Activity Monitor displays such high percentages?

enter image description here

enter image description here

enter image description here


Icons:

enter image description here

enter image description here

  • Is it doing that all the time ? Or is it displaying normal CPU usage most of the time ? – Trevör Dec 12 '14 at 6:05
  • For a couple of seconds – Franck Dernoncourt Dec 12 '14 at 6:11
  • I'm not sure of what I am saying and this won't be a really technical answer, but it looks like activity monitor is dividing something (maybe something like the number of CPU calls) by the CPU time, to get some sort of average, the problem is that here CPU TIME = 0 so you get really high numbers. – Trevör Dec 12 '14 at 7:03
  • 1
    I notice that in the menu bar at the top there is a large gap between a 'gear' icon and the TimeMachine icon. (The second screenshot has what looks to be a 'battery' icon I don't recognize.) What usually goes there? Does the menu bar always look like that under normal usage? What are those icons ('gear' & 'battery')? As for the odd CPU%, it is obvious that Activity Monitor is getting some funky data from some app or apps. Notice that the CPU Time and Threads columns are at 0 for each of these funky CPU% measurement processes. (I've also never seen a single character username before. Really?) – IconDaemon Dec 12 '14 at 13:05
  • @TrevörAnneDenise I thought of it at first but then I would tend to think that all 3 screenshots which are the same value (i.e. the maximum displayable %CPU value). – Franck Dernoncourt Dec 13 '14 at 1:57
1

The other suggestions are good, I just wanted to ad that percentages higher than 100 are, oddly enough, not counter intuitive.

very simply if you see more than 100% usage (as was explained to me) it is a combination of the number of cores in the processor (usually 2 to 8) and how busy all the cores are compared to some (unknown to me) baseline.

So getting high percentages are not uncommon but in the end a bit confusing as this question illustrates. And honestly what is going on here, specifically, is beyond me as well.

  • However I think the most you can get to is 1200% on a top MacPro the numbers in the question are something else – Mark Dec 12 '14 at 23:58
  • I wish this explained my case :) But true many people are surprised by this (e.g. people with Windows background). – Franck Dernoncourt Dec 13 '14 at 0:49
  • 100% CPU usage is 100% of one core. So on a Mac Pro, 1200% means 12 cores at 100% usage. Note that a hyper threaded core can go to 200% if both threads are fully utilized. I am reasonably sure that the images shown in the screen captures here are a bug. – Josh Jan 19 '15 at 4:22

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .