Note: This command is experimental and unsupported.
jmap [options]
pid
- options
- This represents the jmap command-line
options. See Options for the jmap Command.
- pid
- The process ID for which the information specified by the options
is to be printed. The process must be a Java process. To get a list of
Java processes running on a machine, use either the
ps command or, if the JVM processes are not
running in a separate docker instance, the jps command.
The jmap command prints details of
a specified running process.
Note:
This command is unsupported and might not be available in future
releases of the JDK. On Windows Systems where the
dbgeng.dll file isn't present, the Debugging
Tools for Windows must be installed to make these tools work. The
PATH environment variable should contain the
location of the jvm.dll file that's used by
the target process or the location from which the core dump file was
produced.
- -clstats
pid
- Connects to a running process and prints class loader statistics of Java
heap.
- -finalizerinfo
pid
- Connects to a running process and prints information on objects awaiting
finalization.
- -histo[:live]
pid
- Connects to a running process and prints a histogram of the Java object
heap. If the live suboption is specified,
it then counts only live objects.
- -dump:dump_options
pid
- Connects to a running process and dumps the Java heap. The
dump_options include:
- live --- When specified, dumps only the
live objects; if not specified, then dumps all objects in the heap.
- format=b --- Dumps the Java heap in
hprof binary format
- file=filename --- Dumps the heap to
filename
Example:
jmap -dump:live,format=b,file=heap.bin
pid