如何在远程Java Web应用程序上进行内存分析

Question

I know we can use tools like JProfiler etc. Is there any tutorial on how to configure it to display the memory usage just by remote monitoring?

Any idea?

Answer 1

you have VisualGC, it's not very advanced but you can see the memory usage of your application (garbage,old, perm etc...)

http://java.sun.com/performance/jvmstat/visualgc.html

to resume : you launch a daemon monitoring on the remote machine ( http://java.sun.com/j2se/1.5.0/docs/tooldocs/share/jstatd.html , see the security parapraph)

JAVA_HOME/bin/jstatd -J-Djava.security.policy=jstatd.all.policy

with a file here called jstatd.all.policy containing :

    grant codebase "file:${java.home}/../lib/tools.jar" {   
permission java.security.AllPermission;
};

on the remote machine you got the pid of your application to debug with the jps tool :

http://java.sun.com/j2se/1.5.0/docs/tooldocs/share/jps.html#jps

finally on your local machine you launch the visualgc :

visualgc the_pid@remote_machine_address

Answer 2

I usually use YourKit which is an excellent application (license needed).

In your webservers startup/shutdown script (catalina.sh for tomcat) put in:

JAVA_OPTS="-Djava.awt.headless=true -agentlib:yjpagent -Xrunyjpagent:sessionname=Tomcat"

You'll need YourKit already downloaded and added to your library path (I do this in catalina.sh as well):

LD_LIBRARY_PATH=$LD_LIBRARY_PATH:~/yourkit/yjp-6.0.16/bin/linux-x86-32

You can then launch the YourKit client on your local desktop and remotely connect.

Answer 3

You can change to VM params of your Java application to allow remote profiling something like -agentlib:jprofilerti=port=25000

General explanation of JProfiler .

Examples:

• NetBeans

• Intellij

Answer 4

Profile your application using Jprofiler. Below are the steps to configure your Tomcat with Jprofiler.

1. In Linux machine open .bash_profile file from /root directory.
   Enter jprofiller location (using below command export) in

    .bash_profile file export LD_LIBRARY_PATH=/dsvol/jprofiler6/bin/linux-x86 

2. Go Tomcat installation directory. Open catalena.sh file from bin folder.
   Enter the below details in catelana.sh file (only red color information and black color you can find by default in catalena.sh file).

    export JPROFILER_HOME JAVA_OPTS="-Xms768m -Xmx1024m -XX:PermSize=256m -XX:MaxPermSize=256m -Dfile.encoding=UTF8 -agentpath:/opt/Performance/jprofiler7/bin/linux-x86/libjprofilerti.so=port=8849 $CATALINA_OPTS" 

3. Start the server from bin folder by executing the starup.sh command

Answer 5

I've heard good things of VisualVM and here is an article on how to it up remotely:

Java VisualVM to profile a remote server

EDIT : I wrote a blog post on how to setup remote profiling through an SSH tunnel here:

http://kamilmroczek.com/2012/11/16/168787859/