GCToolkit: Microsoft’s Open-Source Tool for Analyzing Java Garbage Collection Logs and Memory State
Microsoft’s Java Engineering Group has made a significant contribution to the Java development community by open-sourcing the Microsoft GCToolkit. This toolkit, now available on GitHub under the MIT license, offers a suite of libraries designed to facilitate the analysis of Java garbage collection (GC) log files. By parsing these logs into discrete events, the GCToolkit enables developers to perform intricate and customized analyses of managed memory within the JVM.
Released in early August, GCToolkit consists of three main Java modules. The first module is the API, which serves as the primary interface for interacting with the toolkit. It abstracts the complexity involved in using the parser and Vert.x-based messaging system, allowing users to analyze GC logs with just a few method calls. The second module is the GC log file parser, a robust component built with regular expressions and dedicated code to reliably interpret GC log files.
The third module incorporates a messaging backplane based on the Vert.x toolkit, known for its capabilities in building reactive applications on the JVM. This backplane utilizes two message buses to handle the data flow. The first bus streams log lines from the GC file to various listeners, which parse the data into events representing GC cycles or safe points. These events are then published on the second message bus, where they are further processed by listeners interested in specific types of events.
The GCToolkit’s parser emits discrete JVM events, allowing for detailed data capture and analysis. Developers can use the toolkit to focus on different aspects of GC logs depending on their needs. The toolkit includes an aggregator/aggregation framework that enables the collection and examination of GC log data. Aggregators capture events, while aggregations perform the analysis, providing a flexible approach to understanding GC behavior and memory management.
For those interested in contributing to the GCToolkit, Microsoft has opened up the project for community involvement. Developers can engage in online discussions and contribute to the toolkit’s development. This move follows Microsoft’s earlier release of its own Java distribution, the Microsoft Build of OpenJDK, in May. The company’s support for Java development extends to its Azure cloud platform, reinforcing its commitment to enhancing Java tools and resources for developers.