Limitations on Java Profiling

You can collect data on Java programs subject to the following limitations:

• You should use a version of the Java 2 Software Development Kit (JDK) no earlier than JDK 6, Update 3. The Collector first looks for the JDK in the path set in either the JDK_HOME environment variable or the JAVA_PATH environment variable. If neither of these variables is set, it looks for a JDK in your PATH. If there is no JDK in your PATH, it looks for the java executable in /usr/java/bin/java. The Collector verifies that the version of the java executable it finds is an ELF executable, and if it is not, an error message is printed, indicating which environment variable or path was used, and the full path name that was tried.

• You must use the collect command to collect data. You cannot use the dbx collector subcommands or the data collection capabilities of the IDE.

• Applications that create descendant processes that run JVM software cannot be profiled.

• If you want to use the 64-bit JVM software, you must use the -j on flag and specify the 64-bit JVM software as the target. Do not use java -d64 to collect data using the 64-bit JVM software. If you do so, no data is collected.

• Some applications are not pure Java, but are C or C++ applications that invoke dlopen() to load libjvm.so, and then start the JVM software by calling into it. To profile such applications, set the SP_COLLECTOR_USE_JAVA_OPTIONS environment variable, and add the -j on option to the collect command line. Do not set the LD_LIBRARY_PATH environment variable for this scenario.