Date Posted: December 16, 2004
Update: December 5, 2005 Version 1.3: analysis of output from new IBM JVM 1.5.0; new "Multiple File Analysis" modality; new graph and text data; performance and user interface improvements.
Tab navigation
1. Can Diagnostic Tool for Java Garbage Collector be used to examine the data produced by any JVM?
Generally, all JVMs are able to produce output that describes the characteristics of the garbage collector actions; however, each JVM output has its own format. Moreover, the output can, and generally does, change between releases of the same JVM.
Diagnostic Tool for Java Garbage Collector is written for analyzing the output of the IBM JVMs. In order to understand the information produced by the garbage collector, the tool uses parsers; each parser is able to decode a well-defined format, so generally a parser is only pertinent to one version of JVM. Diagnostic Tool for Java Garbage Collector 1.3 comes with three built-in parsers for IBM JVM 1.5.0, IBM JVM 1.4.2, and IBM JVM 1.2.2. These parsers were not tested with all the other versions of the IBM JVM, so each parser is likely able to parse the data produced by some other versions of the IBM JVM; for instance, the JVM 1.4.2 parser should also work well with the JVM 1.3.x. If you need to use Diagnostic Tool for Java Garbage Collector to read an unsupported format, you could code your own parser by implementing the GCParser interface, as Diagnostic Tool for Java Garbage Collector will be able to use it as a plug-in.2. How can I code my own parser to examine data produced by an unsupported JVM?
You can code your parser by implementing the GCParser interface, as long as the verbose output of the JVM gabage collector is compatible with some assumptions. The documentation that comes with Diagnostic Tool for Java Garbage Collector explains both the assumptions and the details of the implementation.
