3 Replies Latest reply: Dec 12, 2008 2:23 AM by 800408 RSS

    memory viewr

    800408
      Hi David,
      during our discussion with sun enginneers one of our engineer ask a question.
      he ask if there is somthing like tsv but not for thredas but for memory.
      his basic idea was :
      i want to know how much memory left in my machine and so i can see when my garabasge collctor boosted.
      if it will be with tsv (in one view) its an optimal solution.
      because in the same view i can see the threads and gc and memomory amount.
      i hope our suggestion is clear enough.
      i want to know what you think about.
      Thanks
      Gabi
        • 1. Re: memory viewr
          807557
          Gabi,

          Take a look at our tools page:

          http://java.sun.com/javase/technologies/realtime/reference/doc_2.1/release/JavaRTS-T3.html

          I think VisualVM may give you what you want. Note I haven't used it myself.

          David Holmes
          • 2. Re: memory viewr
            807557
            Hi,

            There are some restrictions on the use of VisualVM, mainly because the Heap Visualiation tools
            are based on safepoint that will disrupt the predicatability. The main benefit of VisualVM is to inspect
            the Heap, seeing how many Objects of each class exist. This can be done with JavaRTS to inspect
            core files, not live processes (but you can easily generate a core from a live process if you don't mind losing predicatability).

            On the other hand, if you just want to know more about the amount of memory consumed, you can do much better.
            Please have a look at the memory and RTGC related probes in our DTrace provide:
            http://java.sun.com/javase/technologies/realtime/reference/doc_2.1/release/JavaRTSDTraceProvider.html

            You can easily write a DTrace script to analyze memory consumption WITHOUT disrupting the application.

            In fact, you could slightly edit the DTrace scripts coming with TSV to print some user event depending on memory consumption. They will appear on your TSV window:
            http://java.sun.com/javase/technologies/realtime/reference/TSV/JavaRTS-TSV.html#userevents

            Feel free to edit these scripts to monitor what you are interested in with very little interference. This is the big benefit of DTrace and TSV !

            Feedback is welcome if you'd like to monitor something that is not yet accessible through our DTrace provider.

            Bertrand.
            • 3. Re: memory viewr
              800408
              Hi Bertrand, David,
              Thanks for your answers.
              im sure we will talk more on the next months since we already got sun support.

              Thanks again.
              have a nice day
              Gabi