Customization Procedures

This topic describes the preferences you can set for the Memory Leak Detector.

To open the preferences window for the Memory Leak Detector:

• Choose Window then Preferences

  The Preferences window opens.

• In the Preferences window, choose JRockit Mission Control then Memory Leak Detector.

Communication Settings

You can choose between the following communication options for TCP port of the Memory Leak Protocol (MLP):

• Let OS choose

  The communication settings are configured by the operating system. This is a convenient choice if you are not sitting behind a firewall.

• Use fixed port

  You specify the communication port manually. Use this when you are running one JRockit JVM behind a firewall.

• Use port relative to JMX port

  Use this option when you are running several JVMs on the same computer and the computer is behind a firewall. Select an offset (a number between 1 and 65535) that will be added to the JMX port (wrapping around if needed) and used as the TCP port for the MLP communication.

Graphs Settings

You can set the following options for graphs in the Memory Leak Detector:

• Animate layouts

  When selected, animates the expansion of a node on the Type Graph and the Instance Graph.

• Automatically center the last expanded node

  When selected, centers a type in the viewing area for the Type Graph and the Instance Graph.

• Number of referred nodes to add when a node is expanded

  When set, controls how many nodes you want to be displayed in the Types tab and Instances tab when clicking the plus sign. If you specify a very high number, the view can become cluttered.

• Show fully qualified class names in graph nodes

  When selected, displays the complete class name in the graphs of the Type Graph and the Instance Graph.

Instance Limits

You can set the following limits for instance navigation and analysis:

• The maximum number of array elements to show, before grouping into ranges

  In the Instance Inspector, if an array has more elements than this number (100 by default), the elements will be grouped into ranges, for example [0 ... 99], that can be individually expanded to show the actual array elements. (In addition, for very large arrays, if the number of grouped ranges becomes larger than this, they will be grouped into an additional level, for example [0 ... 9999], and so on.)

• Maximum depth to search for a GC root

  This is the maximum number of backward steps that will be taken to find a garbage collection root when selecting Expand To Root. If no root is found within this limit, no node expansion will be performed.

• Maximum number of instances to list for a single type

  Use this value to set the number of instances you want to list when selecting List All Instances of a type.

• Maximum number of instances to list for relations between two types

  Use this value to set the number of instances you want to list when selecting List referring instances on a type relation.

• Maximum keep alive size to trace, in bytes

  The Memory Leak Detector counts the amount of data kept alive by any given object until it reaches this value.

• Timeout in seconds for any instance operation

  This value limits the extra time used, beyond the time required by any garbage collector phases, for finding a path to root or instances that participate in a type relation. If the timeout expires, a partial result may be shown, depending on the operation.

Trend Settings

You can set the following properties for the Trend tab:

• Lowest heap usage to report.

  Specifies the minimum ratio of the heap that a type should occupy for it to be reported in the trend table. Types whose total size occupy less than this ratio of the total heap will be ignored. Specify zero to see all types.

• Trend refresh interval.

  Specifies the maximum time in seconds between updates to the trend table. The trend table may be updated more frequently, since garbage collections always update the trend table. This setting does not affect the growth rate calculation accuracy.