A profiler is a performance analysis tool that allows you to reveal hot spots in the application that result in either high CPU utilization or high contention for shared resources. Some common profilers are:
Wily Technology, Inc. provides management solutions for large-scale, real-time production Web applications, applications servers, portal solutions and integration middleware.
SPECjbb2000, a software benchmark product developed by the Standard Performance Evaluation Corporation (SPEC). SPECjbb2000 is designed to measure a system's ability to run Java server applications.
ECPerf Benchmark Kit, a software benchmark product developed under the Java Community ProcessSM Program that is designed to measure performance and scalability and assist the J2EE user in understanding J2EE scalability and tuning.
SPECjAppServer2001 (Java Application Server), a client/server benchmark for measuring the performance of Java Enterprise Application Servers using a subset of J2EE API's in a complete end-to-end web application.