Identifying memory-intensive classes

The performance of a program can be greatly enhanced by identifying and either eliminating or modifying classes that take up large portions of the program's memory. You can use Class Statistics view to identify these classes.

Follow these steps:

  1. Ensure that the collection of execution flow information has been enabled, which you do when launching or attaching to the application to be profiled.  Select the profiling option, My application is too slow then, from the Details options, select Show Execution flow graphical details
  2. Select the appropriate profiling resource in the Profiling Monitor view.
  3. Right click, then select Open With > Class Statistics.  The selected view opens. 
  4. Ensure that the Active Size and Total Size columns appears in the view.  If they do not, then right click, and select Choose Columns.  Check both Active Size and Total Size.  Click Up to move it nearer the top.
  5. Notice which classes have the greatest Total Size value; these are the most memory-intensive classes.  Use the Active Size column to see the total size for the instances not garbage collected yet. (To sort the column click its title.)

Related concepts
Overview of the Profiling Tool
Statistical views

Related tasks
Profiling an application
Launching or attaching a Java process