New Relic is a monitoring and observability solution that helps sysadmins and developers understand their infrastructure systems by providing real-time data and insights. It supports various operating systems, including Windows, Linux, macOS, Docker, and Kubernetes, and can be installed on any system, including virtual machines, private or public clouds, and even local machines. The tool provides a range of features, such as dashboards, alerts, metrics, logs, and event explorers, to help identify root cause issues in infrastructure systems. Installation is relatively straightforward, requiring only an active New Relic account, a system to instrument, and internet connectivity. Once installed, users can use stress testing tools like stress-ng to simulate various scenarios and test their system's performance in real-time.