This section covers the most fundamental command-line switches that control garbage collection in JRockit. For more advanced manipulation of the memory system, for example tuning compaction, please refer to Chapter 5, Benchmarking and Tuning.
Following are the most fundamental command-line switches for interacting with the JRockit memory system.
Running JRockit with –Xverbose:gc will, similar to –Xverbose:codegen, output plenty of verbose information on what the JVM memory management system is doing. This information includes garbage collections, where they take place (nurseries or old space), changes of GC strategy, and the time a particular garbage collection takes.
-Xverbose:gc (or -Xverbose:memory) is, except for JRockit Mission Control, the main information provider when it comes to studying garbage collector behavior for an application.
Here is an example of the output generated by –Xverbose:gc:
hastur:material marcus...