I've searched for an exhaustive explanation of the meaning of each event monitored by the perf stat command;

I've found a tutorial which explains quite well how to use different the features of the perf tool. However, it doesn't explain the meaning of several events that can be observed (and there are a lot!!).

Someone know where is a quite simple and complete documentation about the events listed by the perf list command?

In particular, I'm interested in finding out the percentage of cpu used by some application I wrote. Can i measure it directly through cpu-clock or task-clock? What's the meaning of these two events?

Thanks in advance