Performance profiler for a java application

Question

I need to optimise a Java application. It makes some 3rd party calls. I need some good tool to accurately measure the time taken by individual API calls. To give an idea of complexity- the application takes a data source file containing 1 million rows, and it takes around one hour to complete the processing. As a part of processing , it makes some 3rd party calls (including some network calls). I need to identify which calls are taking more time then others, and based on that, find out a way to optimise the application.

Any suggestions would be appreciated.

Answer 1

I can recommend JVisualVM. It's a great monitoring / profiling tool that is bundled with the Oracle/Sun JDK. Just fire it up, connect to your application and start the CPU-profiling. You should get great histograms over where the time is spent.

Getting Started with VisualVM has a great screen-cast showing you how to work with it.

Screen shot:

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Another more rudimentary alternative is to go with the -Xprof command line option:

-Xprof

Profiles the running program, and sends profiling data to standard output. This option is provided as a utility that is useful in program development and is not intended to be be used in production systems.