When I run TOP, all processes report 0.0 cpu usage. I look in /proc/[pid]/stat and I also see 0.0 cpu usage for all processes. However I can get overall cpu usage from most tools. I had this problem before and it fixed itself when I rebooted. However I had to reboot for an update and it seems it will not fix itself after a reboot. Do people have any idea why the per-process cpu usage is not being reported? What can I do to fix it? It is not critical, but it is nice to see these stats.
I recommend using htop, not top. You can configure htop to show activity on every core seperately:
Hit F2 or click »F2|Setup«, then select »Meters -> CPUs« to your liking. You can configure the upper left and the upper right of htop seperately.
Also, go to Setup/Display Options (right under the »Meters« entry). A few niceties are hidden away there.
Another trusty utility that goes way back (I’ve used it since the early 1990s) is xosview:
Customizing xosview means editing X resources in your local ~/.Xdefaults file:
XOsview*background: grey40 XOsview*memCacheColor: LightSeaGreen XOsview*geometry: 664x420 ...
If you use KDE, you probably also have the KDE System Monitor, a.k.a. KSysGuard, installed. It shows the task list in one tab, and your CPU graphs on another. It’s customizable with context menus (right-click, then select »Properties«).