NonStop Server for Java 7.0 Programmer's Reference

Other HeapDump options
In addition to -XX:+HeapDump, the following three different HeapDump options are available:
-XX:+HeapDumpOnCtrlBreak, -XX:+HeapDumpOnOutOfMemoryError, and
-XX:+HeapDumpOnly.
Table 8 (page 61) lists the heap dump options.
Table 8 HeapDump options
FilenameFormatTriggerOption
java_<pid>_<date>_<time>_heapDump.hprof.txtASCII; Set the
_JAVA_BINARY_HEAPDUMP
SIGQUIT-XX:+HeapDump
environment variable to
obtain binary
java_<pid>.hprof.<millitime>BinarySIGQUIT-XX:+HeapDumpOnCtrlBreak
java_<pid>.hprof or the file
specified by
—XX:HeapDumpPath=file
BinaryOut of
Memory
-XX:+HeapDumpOnOutOfMemoryError
java_<pid>_<date>_<time>_heapDump.hprof.txtASCII; Set the
_JAVA_BINARY_HEAPDUMP
SIGWINCH-XX:+HeapDumpOnly
environment variable to
get binary
The heap dump options are described as follows:
• -XX:+HeapDumpOnCtrlBreak
It enables taking snapshots of the Java heap when a SIGQUIT signal is sent to the
Java process, without using the JVMTI-based —Xrunhprof:heap=dump option.
This option is similar to the —XX:+HeapDump option, except the output format,
which is in binary hprof format and the output is placed in a filename with the
naming convention java_<pid>.hprof.<millitime>.
If the environment variable _JAVA_HEAPDUMP is set, and the
-XX:+HeapDumpOnCtrlBreak option is specified, both hprof ASCII and binary
dump files are created when a SIGQUIT is sent to the process.
For example, the following files are created:
◦ java_27298.hprof.1152743593943
◦ java_27298_060712_153313_heapDump.hprof.txt
If JAVA_BINARY_HEAPDUMP is set, and the —Xrunhprof:heap=dump command
is run, both hprof ASCII and binary files are produced for this option.
• -XX:+HeapDumpOnOutOfMemoryError
It enables dumping the Java heap when the Java process encounters a
java.lang.OutOfMemoryError exception. The heap dump filename defaults
to java_pid<pid>.hprof in the current working directory. The option
—XX:HeapDumpPath=file can be used to specify the heap dump filename or a
directory where the heap dump file must be created. The only heap dump format
generated by the —XX:+HeapDumpOnOutOfMemoryError option is the hprof
binary format.
GC profiling 61