You use the jmap
command to print details of a specified process. This command is experimental and unsupported.
Synopsis
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 the jps command.
Description
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.
Options for the jmap Command
-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