Recently I got email from customer, that our product consumes relatively lot of CPU on idle. About 3%-7%. He is using old notebook and as result fan is constantly cycles between on and off state and it is really annoying. I decided to check this because very often it could be sign of bigger problems.

Usually for cases like this I am asking customer to run PerfView to collect events that happens during problematic time. It is quite useful application; it is developed by Microsoft and completely free. It has quite unusual interface and requires some learning. There have links to learning videos from app itself.

Anyway, customer was nice and provided quite a few PerfView captures in different state