Created attachment 141587 [details] CPU usage graph scale, showing more than 100% total CPU usage. The default interface of the new System Monitor (I bet) simply sums the individual core usage percentages and plots them. This means that the scale on the y-axis goes up to 400% (since my CPU has 4 cores), which makes no sense. I think somewhere there's a "divided by ncores" missing in the code. :)
There's not. It is a stacked view, and every core can go up 100%, then you will reach a sum that is 400% of the value of a single core. You can toggle stacked view, or choose to show only an overall CPU.
OK, then maybe it makes more sense to modify the default title to "CPU cores", because simply "CPU" makes me think of something else (where it's wrong to put 400%). Better even to simply hide the y-axis labels. I know I can change the title by myself (the whole configurability of this thing is awesome). This is now more a problem of how DEFAULTS are presented and setup. And by default, it just looks weird/counterintuitive (well, to me).
We need to do something, it's been asked by enough people that we definitely have a UI problem. IMHO we should just show total CPU, there's no usable data in seeing cores.
*** This bug has been marked as a duplicate of bug 434040 ***