The CPU Usage (Sampled) data gives you an approximation of how much time is spent in different call stacks but it cannot differentiate between a small number of expensive function calls and a large number of cheap calls. I set this as a conditional breakpoint that would only halt after being hit one billion times because I didn’t actually want Explorer.exe to halt in the debugger – I just wanted Visual Studio to count how many times the breakpoint was hit. Acronis True Image is iterating through a list of running processes many times – sometimes thousands of times – whenever my monitor is plugged or unplugged.