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jmap(1)			     Troubleshooting Tools		       jmap(1)

       jmap - Prints shared object memory maps or heap memory details for a
       process,	core file, or remote debug server. This	command	is
       experimental and	unsupported.

       jmap [ options ]	pid

       jmap [ options ]	executable core

       jmap [ options ]	[ pid ]	server-id@ ] remote-hostname-or-IP

	      The command-line options.	See Options.

       pid    The process ID for which the memory map 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(1) command.

	      The Java executable from which the core dump was produced.

       core   The core file for	which the memory map is	to be printed.

	      The remote debug server hostname or IP address. See

	      An optional unique ID to use when	multiple debug servers are
	      running on the same remote host.

       The jmap	command	prints shared object memory maps or heap memory
       details of a specified process, core file, or remote debug server. If
       the specified process is	running	on a 64-bit Java Virtual Machine
       (JVM), then you might need to specify the -J-d64	option,	for example:
       jmap-J-d64 -heap	pid.

       Note: This utility is unsupported and might not be available in future
       releases	of the JDK. On Windows Systems where the dbgeng.dll file is
       not present, 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 is used by the	target process or the
       location	from which the crash dump file was produced, for example: set

       <no option>
	      When no option is	used, the jmap command prints shared object
	      mappings.	For each shared	object loaded in the target JVM, the
	      start address, size of the mapping, and the full path of the
	      shared object file are printed. This behavior is similar to the
	      Oracle Solaris pmap utility.

       -dump:[live,] format=b, file=filename
	      Dumps the	Java heap in hprof binary format to filename. The live
	      suboption	is optional, but when specified, only the active
	      objects in the heap are dumped. To browse	the heap dump, you can
	      use the jhat(1) command to read the generated file.

	      Prints information about objects that are	awaiting finalization.

	      Prints a heap summary of the garbage collection used, the	head
	      configuration, and generation-wise heap usage. In	addition, the
	      number and size of interned Strings are printed.

	      Prints a histogram of the	heap. For each Java class, the number
	      of objects, memory size in bytes,	and the	fully qualified	class
	      names are	printed. The JVM internal class	names are printed with
	      an asterisk (*) prefix. If the live suboption is specified, then
	      only active objects are counted.

	      Prints class loader wise statistics of Java heap.	For each class
	      loader, its name,	how active it is, address, parent class
	      loader, and the number and size of classes it has	loaded are

	      Force. Use this option with the jmap -dump or jmap -histo	option
	      when the pid does	not respond. The live suboption	is not
	      supported	in this	mode.

	      Prints a help message.

	      Prints a help message.

	      Passes flag to the Java Virtual Machine where the	jmap command
	      is running.

       o jhat(1)

       o jps(1)

       o jsadebugd(1)

JDK 8			       21 November 2013			       jmap(1)


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