Linux – Java, VisualVM : Setting up VisualVM properly for Java8 based webapps

configurationjavalinuxmonitoringprofile

I have a Java based webapp which I have deployed on one of our server. Sometimes the JVM died because of out-of-memory error. The application is kinda heavy as it uses Cometd(Push mechanism) heavily and some columns are encrypted. For this, I decided to monitor the application, but for some reason, VisualVM wont show sampling and CPU usage. It says that the JVM is not supported.

The 2nd problem I am having is that the update time of VisualVM is too slow. I want to decrease the intervals between which it monitors, but no luck finding that option as well.

I am running Debian Wheezy, 64 bit and Java8-64bit. The application-container is Apache tomcat and DB is Postgres. Jstatd is already started. I am new to profiling and monitoring, any help would be nice.

Here are the screenshots. Kindly have a look.

Thank you.

Update

Here is the updated screenshot of how it looks without the config mentioned below:

And my catalina.sh has some server config like :

CATALINA_OPTS="$CATALINA_OPTS -server -XX:+UseParallelGC -XX:+UseParallelOldGC -XX:+UseAdaptiveSizePolicy -Dcom.sun.management.jmxremote=true
-Dcom.sun.management.jmxremote.port=portnumer -Dcom.sun.management.jmxremote.authenticate=true 
    -Dcom.sun.management.jmxremote.ssl=false"

Here is after the above configuration with the new GC :

Best Answer

Adding this to target JVM application works for me:

-Djava.rmi.server.hostname=localhost

Related Solutions

Java – How to Set Java Runtime for All Users on a Client PC

Maybe you can try modifying a System Deployment Properties file? Short version of usage below:

You need to create a file named deployment.config and put it in either %SystemRoot%\Sun\Java\Deployment or your JRE's \lib\ directory.
The deployment.config contains a pointer to a deployment.properties file, as below:

deployment.system.config=file\:C\:/Windows/Sun/Java/Deployment/deployment.properties
The deployment.properties file contains the properties that you want to set system-wide, one per line. For my organization, we occasionally have problems with the JRE's caching causing problems, so I disable it with deployment.cache.enabled=false and prevent users from changing the value with deployment.cache.enabled.locked= If you're not sure about the syntax, make the changes for yourself and look at the deployment.properties file normally located in C:\Documents and Settings\<username>\Local Settings\Application Data\Sun\Java\Deployment. At least, I think that's the path in XP. On my Win 7 system it's in AppData\LocalLow\Sun\Java\Deployment.

I don't know if you can set the JRE options like this, but it's worth a shot.

Linux – Enable HugePages on Linux for multiple services/processes

You dont mention your distro/kernel version, but it may be worth noting that recent kernels (2.6.38+) have a feature called transparent hugepages.

You can tell if it is enabled using:

cat /sys/kernel/mm/transparent_hugepage/enabled

It pretty much takes all this burden managing and preallocating hugepages of you.

You can see how much memory is allocated using which page size by running

cat /proc/meminfo | grep AnonHugePages

egrep 'trans|thp' /proc/vmstat

per process usage

grep -e AnonHugePages  /proc/*/smaps | awk  '{ if($2>4) print $0} ' |  awk -F "/"  '{print $0; system("ps -fp " $3)} '

Last three commands taken from RHEL6 support

Interesting info on Transparent HugePages and JVM.

Best Answer

Related Solutions

Java – How to Set Java Runtime for All Users on a Client PC

Linux – Enable HugePages on Linux for multiple services/processes

Related Topic