big cpu usage, but top shows no heavy use process
I have been running to a strange problem. For a few days, a few times a day something seems to take over my machine. Suddenly I can't type, or the key shows up about 5 seconds are being pressed, music players halt, etc.
In anticipation, I had top and htop running. Sure enough, when this business begins htop reports all 8 cores firing at near 100% for a few minutes. However, top is telling me nothing about who is too blame. The cup%sy on top shows heavy usage, but the top processes are nothing remarkable, mostly just top and htop and conky, all running at around 1 or 2% on average.
I am a bit puzzled as to why I can't see the cpu hog so that I figure out what is going on.
My question then: Are there some processes (in kernel space?) that don't show up in top, yet which could be hogging the cpu?