how to tell memory useage of my app in a Mac

i am introducing caching to one of my apps (it calls various service methods to access data from DB), and i want to find out how much extra physical memory it takes.  i have tried the activity monitor and also this:

$ Ps -ef | grep dsp
716566150  3234  1070   0  5:41PM ttys000    1:43.18 /Library/Java/JavaVirtualMachines/jdk1.7.0_51.jdk/Contents/Home/bin/java -Xdebug -Xnoagent -Djava.compiler=NONE -Xrunjdwp:transport=dt_socket,server=y,suspend=n,address=5005 -server -Xms128M -Xmx512M -XX:+HeapDumpOnOutOfMemoryError -XX:PermSize=128M -Dcom.sun.management.jmxremote -Ddsp-env=osgi -Djava.net.preferIPv4Stack=true -Djava.security.egd=file:///dev/urandom -Djava.endorsed.dirs=/Library/Java/JavaVirtualMachines/jdk1.7.0_51.jdk/Contents/Home/jre/lib/endorsed:/Library/Java/JavaVirtualMachines/jdk1.7.0_51.jdk/Contents/Home/lib/endorsed:/Users/212353126/GIA150/dsp-k-1.5.0/lib/endorsed -Djava.ext.dirs=/Library/Java/JavaVirtualMachines/jdk1.7.0_51.jdk/Contents/Home/jre/lib/ext:/Library/Java/JavaVirtualMachines/jdk1.7.0_51.jdk/Contents/Home/lib/ext:/Users/212353126/GIA150/dsp-k-1.5.0/lib/ext -Dkaraf.instances=/Users/212353126/GIA150/dsp-k-1.5.0/instances -Dkaraf.home=/Users/212353126/GIA150/dsp-k-1.5.0 -Dkaraf.base=/Users/212353126/GIA150/dsp-k-1.5.0 -Dkaraf.data=/Users/212353126/GIA150/dsp-k-1.5.0/data -Djava.io.tmpdir=/Users/212353126/GIA150/dsp-k-1.5.0/data/tmp -Djava.util.logging.config.file=/Users/212353126/GIA150/dsp-k-1.5.0/etc/java.util.logging.properties -Dkaraf.startLocalConsole=true -Dkaraf.startRemoteShell=true -classpath /Users/212353126/GIA150/dsp-k-1.5.0/lib/karaf-jaas-boot.jar:/Users/212353126/GIA150/dsp-k-1.5.0/lib/karaf.jar org.apache.karaf.main.Main
716566150  3408  3182   0  5:59PM ttys004    0:00.00 grep dsp

but i am not sure what all the results mean.  for example, what is the memory usage?  is it possible to break the usage down to a finer level, e.g. by thread or service call?  also is there a way to log the usage?