0 Replies Latest reply: Aug 18, 2010 1:25 AM by 843798 RSS

    jmap heap dump doesnt capture all classes?

    843798
      I was using jmap to collect the heap snapshot to analyze the classes loaded by multiple class loaders. However it shows only one set of classes loaded by one class loader while analyzing with jhat tool.

      jmap -dump:format=b,file=/home/work/heap-analysis/heap.bin <process-id>

      jhat -J-mx768m /home/work/heap-analysis/heap.bin

      I have a code which load same application multiple times in single jvm using different class loader instances. This means there will be multiple classes loaded in jvm per class loader. What I wanted to check with jmap and jhat is to verify my intention and do some statistics however I think there is some problem the way jmap collects heap snapshot or in jhat tool while representing the data unless I am doing anything wrong :D

      No doubt they are great tools to help analyze the heaps just wanted to confirm if there is any limitation.

      PS: I have verified the multiple class loading stuff with some other java profilers as well which shows it correctly.