PerfView
PerfView is a CPU and memory performance-analysis tool
PerfView is a free performance analysis tool that helps isolate CPU and memory-related performance issues. It is a Windows tool, but it also has some support for analyzing data collected on Linux machines. It works for a wide variety of scenarios, but has a number of special features for investigating performance issues in code written for the .NET runtime. If you are unfamiliar with PerfView, there are PerfView video tutorials.