XRebel 2.0 Features Enhancements for Enterprise Java 

Java toolmaker ZeroTurnaround has announced the general availability of version 2.0 of its lightweight Java profiler, XRebel.

According to the company, this release comes with extensive usability improvements specifically designed to help users profiling large enterprise Java applications -- such as an improved display of large data sets and the ability to handle very large HTTP sessions. The tool also works with all major application servers and development environments without configuration requirements; XRebel displays alerts in the user's browser via a simple widget. 

"Enterprise applications tend to be larger and more complex, which makes reasoning about performance much harder," Jevgeni Kabanov, founder and CEO of ZeroTurnaround, told ADTmag via e-mail. "XRebel makes performance issues immediately apparent, and the UI is extensively optimized for large applications and large data sets, so you only see things that are relevant to your issue."

When it was release in June 2014, XRebel represented a departure from traditional performance monitors, which had been used primarily by performance experts in dedicated sessions that generated huge amounts of data that had to be interpreted. XRebel is an "always-on, interactive profiler," running continuously in the background, making it the first of its kind to measure and display the performance of Java code from within the development workflow.

"This is a different use pattern," Kabanov said at the time. "XRebel enables developers to continuously test and iterate on their code, to catch more production-related errors before they commit code, and to better understand their codebase. It creates this awesome feedback loop in development that developers didn't have before."

That 1.0 release was able to profile database queries, HTTP sessions, and hidden exceptions. Between version 1.0 and 2.0 the tool has acquired the ability to profile Web services, NoSQL database queries, ORM queries, and even RMI calls.

The upgraded application profiler in XRebel 2.0 breaks down request latency to individual hotspot methods, Kabanov explained. "We can now handle any latency issue you might have, with the IO profiler focusing on heavy remote calls and the application profiler reporting on everything else," he said. "We also rethought how we notify the user when an issue occurs, to reduce false positive interactions. The notifications are now really low key, and you can run XRebel minimized most of the time."

"The beauty of those enhancements is that they make latency issues immediately visible and fixable," he added, "which has been the XRebel creed from Day One. And it's still the lightweight profiler our users have come to know and love."

The Tartu, Estonia-based ZeroTurnaround is probably best known for its JRebel plug-in, which integrates with the Java Virtual Machine (JVM) and app servers on the class loader level, allowing developers to make on-the-fly code changes in Java class files. The company's research and content organization, Rebel Labs, publishes free, vendor-neutral technical resources.

ZeroTurnaround gave the original XRebel a broad beta test among more than 500 organizations. The company expects to have attracted more than 1,000 users by the tool's one-year anniversary.

About the Author

John K. Waters is the editor in chief of a number of sites, with a focus on high-end development, AI and future tech. He's been writing about cutting-edge technologies and culture of Silicon Valley for more than two decades, and he's written more than a dozen books. He also co-scripted the documentary film Silicon Valley: A 100 Year Renaissance, which aired on PBS.  He can be reached at [email protected].