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Tool for viewing objects in permgen

I have some problems with pergene overflow. What tools can I use to see which classes are now loaded into permgen and how much memory do they use? Thank.

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Maybe you have a large code base or interning multiple lines.

Try jmap:

jmap -permstat <pid>

(Note: option permstatnot available on Windows)

Example:

$ jmap -permstat 22982
Attaching to process ID 22982, please wait...
Debugger attached successfully.
Server compiler detected.
JVM version is 17.0-b16
100691 intern Strings occupying 5641096 bytes.
finding class loader instances ..Finding object size using Printezis bits and skipping over...
done.
computing per loader stat ..done.
please wait.. computing liveness..done.
class_loader    classes bytes   parent_loader   alive?  type

<bootstrap>     303     1355992   null          live    <internal>
0xdd159fe8      9       94104   0xdd153c30      live    sun/misc/Launcher$AppClassLoader@0xae7fcfa0
0xdd153c30      0       0         null          live    sun/misc/Launcher$ExtClassLoader@0xae7b0178

total = 3       312     1450096     N/A         alive=3, dead=0     N/A

You can also try dumping the heap into a file and then uploading it to the Eclipse Memory Analyzer , which will provide you with useful information, such as the Suspicious Flow Report and the Dominator tree.

jmap -dump:format=b,file=heap.bin 22982

PermGen -XX:MaxPermSize JVM.

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