The Memory Statistics views displays statistics about the application heap. It provides detailed information such as the number of classes loaded, the number of instances that are alive, and the memory size allocated by every class. Memory statistics are available at the package, class, and instance level.
Prerequisites:
The Memory Statistics view provides a number of controls to allow you to manipulate the information shown within the view:
There are three display modes are available based on the three object types: packages, classes, and instances.
The data displayed depends what object type is selected. The following table summarizes the data available in each display mode.
Column heading | Package statistics ![]() |
Class statistics![]() |
Instance statistics![]() |
---|---|---|---|
Total Instances: The total number of instances that had been created of the selected package, class, or method. | Accumulated by package | Accumulated by class | Count |
Live Instances: The number of instances of the selected package, class, or method, where no garbage collection has taken place. | Accumulated by package | Accumulated by class | Count |
Collected: The number of instances of the selected package, class, or method, that were removed during garbage collection. | Accumulated by package | Accumulated by class | Count |
Total Size: The total size (in bytes) of the selected package, class, or method, of all instances that were created for it, including whatever has been removed through garbage collection. | Accumulated by package | Accumulated by class | Size |
Active Size: The summed size of all live instances. | Accumulated by package | Accumulated by class | Size |
Note: The totals shown in this view represent only the data that has been collected since you started monitoring your process. If you start monitoring your process half way through the execution, you will only see the totals from the point that you started monitoring. As well, in the package mode, only the totals of the collected classes for that package are shown. Classes that you have filtered out will not be included in the totals.
Note: In order for instance level data to be shown for the active size and collected columns in the Memory Statistics view, instance level data must be collected for the Time Analysis profiling type. To collect instance level data, you must perform the following actions on the Profiling Types page for your profiling set:
Note: The profiling views are described here using Java. Profiling data from a different application context might change the terms and syntax used in the views. For more information, see Understanding application contexts in profiling views.
For information on how to access the Profiling Types page for a profiling set, see the following tutorial: Analyzing the profiling data from a Java process.
There are different controls available that allow you to manipulate the columns displayed in this view.
Profiling filters can be applied to the Memory Statistics view to reduce the amount of data shown in the view. Profiling filters can be used across different profiling views as long as the view supports the filter. See the topic on Applying profiling filters for more details.
Other profiling views and source code views can be opened from the Memory Statistics view.
The data within the Memory Statistics view can be exported to available report formats (for example, HTML or XML).
The Memory Statistics view can be refreshed using the Refresh
button in the Profiling Monitor toolbar. When the view is refreshed, changes are marked with delta icons:
Related concepts
Overview of the Profiling Tool
Profiling resources
Related tasks
Applying profiling filters
Profiling an application
Identifying memory-intensive classes
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