Managing, monitoring, and improving application responsiveness is a common need for many software professionals. Whether you develop Java applications or manage them, understanding application responsiveness and the major mechanisms that affect it is key to achieving successful applications and happy users. In this workshop, Gil Tene (CTO, Azul Systems) will provide an in-depth overview of Latency and Response Time Characterization, including proven methodologies for measuring, reporting, and investigating latencies, and and overview of some common pitfalls encountered (far too often) in the field. While most of this discussion will apply to all application environments, some specific considerations in JVM based environments will be covered as part of this workshop. Our discussion will include an exploration of of the common needs and motivations for understanding the behavior of application response time and latency, and ways to successfully capture these descriptions and relate them to business needs. However, even good characterization of bad data is useless. If measurements of response time present false or misleading latency information, even the best analysis can lead to wrong operational decisions and poor application experience. Gil will demonstrate and discusses some common pitfalls, false assumptions and problematic measurement techniques that lead to dramatically incorrect reporting results, and will explain how these false measurements naturally occur using the most common measurement methods and tools in use today. We will discuss the coordinated data omission problem, and ways to work around it, and will introduce and demonstrate how simple and recently open sourced tools can be used to improve and gain higher confidence in both latency measurement and reporting. Garbage Collection, in platforms that use it, is often dominantly responsible for application responsiveness and latency behavior. Gil will review and classify the various garbage collectors and collection techniques available in managed runtimes today. We will define terms and metrics common to all collectors, classify some commonly available collector mechanisms, and discuss the tradeoffs involved in balancing responsiveness requirements against other concerns (like throughput, space, etc.). We will include an interactive discussion of how these tradeoffs play off in the real world. Who should attend: Software developers, architects, technical leaders and anyone with an interest in designing or measuring for latency in software environments.