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JConsole details differ

Raja Nagendra Kumar

Joined: Jun 14, 2008
Posts: 27

I see JConsole when launched does show different memory compartments for different applications. When tried with jdk build 1.6.0_14-b08 on jconsole it self it shows the following non heap compartments

1. Memory Pool - Code Cache
2. Memory Pool - Perm Gen
3. Memory Pool - Perm Gen [shared -rw]
4. Memory Pool - Perm Gen [shared -ro]

Where as on a ant build monitoring of my build it shows only two

1. Memory Pool - Code Cache
2. Memory Pool - CMS Perm Gen

Why is such difference.. Looking for a good document to understand more.. Also, I read some where that jdk has tools to jps, jstat, jstatd, jmap, jhat, .. etc.. has any one used these tools successfully in able to find what objects are stored in each of these compartments.. specially navigating from the gcroots down the children.


Raja Nagendra Kumar,
Kees Jan Koster
JavaMonitor Support

Joined: Mar 31, 2009
Posts: 251
Dear Raja,

That is because the two JVM's use different garbage collector strategies. Read up on JVM GC tuning to see what strategies exist.

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