I recently began to see some odd behavior on my MacBook Pro on Mountain Lion. I noticed the fans coming up and applications behaving sluggish. I checked the ActivityMonitor (see below) and the results kept me puzzled: Although I list all processes, only very few show up that cause medium CPU usage, still the system CPU is at close to 70%.
I've wondered about this behavior quite a while ago already and then - just as now - the problem just went away after about 10-15 minutes of lagging and fanning.
What can cause these symptoms? Why isn't the "thing" causing the CPU load showing up in the process list? How can I diagnose the issue in more detail?
UPDATE: I seem to could have hunted it down to Skype causing the trouble. I've notice it running on 100% CPU and quit it. Now it seems to hang in some kind of error state according to
ps. Unfortunately I cannot kill it :(.
$ ps -xo pid,ppid,stat,command | grep Skype 85267 185 ?E (Skype) 79202 339 R+ grep Skype $ kill -9 85267 $ ps -xo pid,ppid,stat,command | grep Skype 85267 185 ?E (Skype) 79220 339 R+ grep Skype