jmp - a Java Memory Profiler.

java -Xrunjmp:[OPTION1,OPTION2,...] MainClass

jmp is a Java memory profiler which is dynamically loaded by executing the java program with the -Xrunjmp option. Currently the kaffe virtual machine and the non-free JDK/JREs are supporting the profiling extensions.

help

print available options

nogui

run jmp without an user interface

dumpdir=<directory>

specifies a directory for writing the data and heap files

dumptimer=<seconds>

specifies to dump the data at a fixed intervall

filter=[[+-][filtertype:]][name]

adds an initial filter for name. It is possible to give several filter to include more than one package. If you want several filters you have to write them as multiple options. Use + for and inclusive filter, use - for an exclude filter. + is the default and may be left out.

The available filtertypes are class, package, recursive and all. The name is either the class name (for filtertype class), a package name (for filtertype package and recursive) or any free text (for the filtertype all). Filters apply in the ordering given on the command line.

Example: filter=package1,filter=some.package,filter=-package:some.package.sub

threadtime

use thread time instead of absolute time

noobjects

turn object profiling off

nomethods

turn method profiling off

nomonitors

turn monitor profiling off

allocfollowsfilter

group object allocations into filtered methods

Examples of how jmp can be run for different profiling tasks.

java -Xrunjmp:noobjects,nomethods,nomonitors my.MainClass

This will start jmp with a minimum of tracing. This is very useful if you have an initialization that takes much time. Once your application has reached a suitable state for profiling you enable the profiling you need.

java -Xrunjmp:noobjects,nomonitors,filter=my my.MainClass

This will start jmp with only method tracing on. An initial filter for classes in my and sub packages is also set.

java -Xrunjmp:nomethods,nomonitors,filter=my my.MainClass

This will start jmp with only object tracing on. Filter as above.

java -Xrunjmp:nomonitors,filter=my my.MainClass

This will start jmp with object and method tracing. Filter as above.

the website for further information <http://www.khelekore.org/jmp/>

This manpage is based on the jmp user guide and written by Wolfgang Baer <WBaer@gmx.de>, for the Debian project (but may be used by others).