Debugging performance problems can be a daunting task, especially when you are short on time and lack proper tools that integrate nicely with your custom application landscape. Thermostat was designed to answer the most interesting questions related to performance measurement and application monitoring. It takes advantage of performance metrics and serviceability features of OpenJDK to provide a holistic view of the system. In this session, attendees will get a chance to see Thermostat in action as it is used to analyse programs, gather data, and debug issues affecting performance and functionality.