jmx keys

[pradhanparas]

Hi,

I was able to make java gateway work to monitor java. In the documentation I dont see the possbile key parameters except this

jmx["java.lang:type=Memory","HeapMemoryUsage.used"]

I would like to get the values for

Eden used/free
Survivor used/free
Old used/free
Permanent used/free

Where do i refer?

Thanks
Paras.

[Slash]

See step 5 in my post here to find the correct bean name with jmxterm : http://www.zabbix.com/forum/showthread.php?t=36714

For the classic memory pool, just create items like this :

jmx["java.lang:type=MemoryPool,name=CMS Old Gen",Usage.committed]
jmx["java.lang:type=MemoryPool,name=CMS Old Gen",Usage.init]
jmx["java.lang:type=MemoryPool,name=CMS Old Gen",Usage.max]
jmx["java.lang:type=MemoryPool,name=CMS Old Gen",Usage.used]

Just change "CMS Old Gen" by "CMS Perm Gen", "Code Cache", "Par Eden Space", "Par Survivor Space" and you'll have all the memory pool monitored ;-)

[pradhanparas]

Thanks for your reply slash


I am not sure why but all of the CMS old gen.* , Par Eden and Par Survivor Space are greyed out and says not supported.

Any idea why?

I have PS old Gen. * working though.

Thanks in advance
Paras.

[Slash]

This simply means that you have different beans than me.

Use jmxterm to determine what beans you have and want to monitor (use google to download it).

For example, I found my beans this way :

# java -jar jmxterm-1.0-alpha-4-uber.jar 
$>open example.com:77777
#Connection to example.com:77777 is opened
$>domains
#following domains are available
Catalina
JMImplementation
Users
axis
com.sun.management
java.lang
java.nio
java.util.logging
$>domain java.lang         
#domain is set to java.lang
$>beans
#domain = java.lang:
java.lang:name=CMS Old Gen,type=MemoryPool
java.lang:name=CMS Perm Gen,type=MemoryPool
java.lang:name=Code Cache,type=MemoryPool
java.lang:name=CodeCacheManager,type=MemoryManager
java.lang:name=ConcurrentMarkSweep,type=GarbageCollector
java.lang:name=Par Eden Space,type=MemoryPool
java.lang:name=Par Survivor Space,type=MemoryPool
java.lang:name=ParNew,type=GarbageCollector
java.lang:type=ClassLoading
java.lang:type=Compilation
java.lang:type=Memory
java.lang:type=OperatingSystem
java.lang:type=Runtime
java.lang:type=Threading
$>bean java.lang:name=CMS\ Old\ Gen,type=MemoryPool 
#bean is set to java.lang:name=CMS Old Gen,type=MemoryPool
$>info
#mbean = java.lang:name=CMS Old Gen,type=MemoryPool
#class name = sun.management.MemoryPoolImpl
# attributes
  %0   - CollectionUsage (javax.management.openmbean.CompositeData, r)
  %1   - CollectionUsageThreshold (long, rw)
  %2   - CollectionUsageThresholdCount (long, r)
  %3   - CollectionUsageThresholdExceeded (boolean, r)
  %4   - CollectionUsageThresholdSupported (boolean, r)
  %5   - MemoryManagerNames ([Ljava.lang.String;, r)
  %6   - Name (java.lang.String, r)
  %7   - ObjectName (javax.management.ObjectName, r)
  %8   - PeakUsage (javax.management.openmbean.CompositeData, r)
  %9   - Type (java.lang.String, r)
  %10  - Usage (javax.management.openmbean.CompositeData, r)
  %11  - UsageThreshold (long, rw)
  %12  - UsageThresholdCount (long, r)
  %13  - UsageThresholdExceeded (boolean, r)
  %14  - UsageThresholdSupported (boolean, r)
  %15  - Valid (boolean, r)
# operations
  %0   - void resetPeakUsage()
#there's no notifications
$>get Usage
#mbean = java.lang:name=CMS Old Gen,type=MemoryPool:
Usage = { 
  committed = 25666686976;
  init = 1409286144;
  max = 126842503168;
  used = 20070232200;
 };

Meaning that a bean named "java.lang:name=CMS Old Gen,type=MemoryPool" exist with an "usage" parameter with 4 value, so the jmx value I want is finally "java.lang:name=CMS Old Gen,type=MemoryPool,usage.committed/init/max/used".

Anyway, just look arround with jmxterm and you'll find what you want to monitor, there is no mystery here ;-)

[pradhanparas]

jmxterm helped me to find out the correct beans. Thank you very much Slash !

One last question, I could see

java.lang:name=PS Survivor Space,type=MemoryPool

Aren't there Survivor0 and Survivor1? By looking at the output from the above bean, I see Free from S0 and Used from S1.

Thanks!
Paras.


beans o/p:

java.lang:name=Code Cache,type=MemoryPool
java.lang:name=CodeCacheManager,type=MemoryManager
java.lang:name=PS Eden Space,type=MemoryPool
java.lang:name=PS MarkSweep,type=GarbageCollector
java.lang:name=PS Old Gen,type=MemoryPool
java.lang:name=PS Perm Gen,type=MemoryPool
java.lang:name=PS Scavenge,type=GarbageCollector
java.lang:name=PS Survivor Space,type=MemoryPool
java.lang:type=ClassLoading
java.lang:type=Compilation
java.lang:type=Memory
java.lang:type=OperatingSystem
java.lang:type=Runtime
java.lang:type=Threading

[Slash]

Sorry but I have no idea

I don't have survivor0 and survivor1 on my beans, which seems logical since there is only one survivor memory pool.

Or maybe I misunderstood you?

[Tec_Technician]

Help for future

Hi all!!

I know this thread is old but i have another way to help, and I think that could help for future search on the forum:

If you are not sure about what Mbeans you have, you can install Java VisualVM and download and active the plugin MBeans, so you could see the list of MBeans in a folder tree, easy to check the route and the ObjectName.

Hope this could help.

Best regards,




Number of hosts 50,Number of items +3600,Number of triggers +1500. Zabbix beginner.

[Slash]

Yes, this topic is old... I don't know about JAVA Visual VM but we now simply use jconsole, which is bundled with OpenJDK and Oracle JDK.

You just need to start the target JVM with this kind of option:

-Dcom.sun.management.jmxremote
-Dcom.sun.management.jmxremote.port=12345
-Dcom.sun.management.jmxremote.ssl=false
-Dcom.sun.management.jmxremote.authenticate=false

You may also need this, depending on the configuration of you server/dns:

-Djava.rmi.server.hostname=server_FQDN_here

This is the simplest configuration (do not use in prod since it doesn't ask for a password).

You may also add a password authentication with:

-Dcom.sun.management.jmxremote.authenticate=true
-Dcom.sun.management.jmxremote.access.file=path_to_an_access_file
-Dcom.sun.management.jmxremote.password.file=path_to_a_password_file

Look at the official JAVA configuration to create correct files for access and password.