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J. Duke319a3b92007-12-01 00:00:00 +00001#
2# Copyright 2004-2007 Sun Microsystems, Inc. All Rights Reserved.
3#
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31
32gctest
33
34This agent library can be used to track garbage collection events.
35
36You can use this agent library as follows:
37
38 java -agentlib:gctest ...
39
40To get help on the available options try:
41
42 java -agentlib:gctest=help
43
44See ${JAVA_HOME}/demo/jvmti/index.html for help running and building agents.
45
46The Events JVMTI_EVENT_GARBAGE_COLLECTION_START,
47JVMTI_EVENT_GARBAGE_COLLECTION_FINISH, and JVMTI_EVENT_OBJECT_FREE
48all have limitations as to what can be called directly inside the
49agent callback functions (e.g. no JNI calls are allowed, and limited
50interface calls can be made). However, by using raw monitors and a separate
51watcher thread, this agent demonstrates how these limitations can be
52easily avoided, allowing the watcher thread to do just about anything
53after the JVMTI_EVENT_GARBAGE_COLLECTION_FINISH event.
54