Memory Analysis 

The Memory Analysis tool is used for displaying the current level of memory consumption.

For this purpose, the tool provides two display screens with different information.

 You can switch between the two screens by clicking the respective icons.

 

Memory Sizes

In the screen Memory Sizes, values for the internal session as well as special memory areas are displayed. All specifications are in bytes.

For the internal session, the allocated memory and the memory actually used are displayed. For special memory areas (see Virtual Address Space of a Work Process), the following values are displayed:

·        Heap memory (private memory)

·        Roll memory

·        Short memory (memory for storing interim results – for example, from the screen that is automatically cleared after each dialog step)

·        Paging memory

 

Memory Objects

In the Memory Objects screen, a ranked list of all memory objects, sorted by size, is displayed. You can change the number of entries in this list through the input field Entries. Using the View selection field, you can set the memory object display. The following view options are possible:

·        Memory objects

·        Types

·        Aggregates (cycles)

In the Memory Objects view, you see individual memory objects (class objects, anonymous data objects, internal tables and strings) displayed.

When you select the Types view, the class objects and anonymous data objects are grouped fort he respective class and the respective type. The memory used is added up for the individual objects. In the case of classes, the static memory of the classis also taken into consideration.

The Aggregates (Cycles) view also groups individual memory objects together – but, in this case, only those that are part of a strongly connected component. A strongly connected component is characterized by the following property: For every two elements A and B of such a component, there is a path in the object graph from A to B and from B to A. The result is that the elements of a strongly connected component can be deleted only by the garbage collector, provided all outside references to elements of the component were deleted. Strongly connected components can therefore be viewed as composite objects that can only be deleted as a whole. 

 

Settings

You call the Settings window through the Services tool. You can use this to control the behavior of the memory object ranked lists.

·        Filter: Certain types of memory objects (internal tables, strings, class objects or classes, and anonymous data objects or their types) can be filtered out of the ranked list.

·        Sorting: The ranked list can be sorted according to included or referenced memory.

·        Updating: The updating of the ranked list can take place automatically or by request. In the latter case, a Refresh button is also displayed.

Other Services

In addition to the settings, the Service menu provides the following functions:

·        Create Memory Snapshot: Creating a memory snapshot on the application server for subsequent analysis using the transaction S_MEMORY_INSPECTOR.

·        Compare Memory Snapshots: Starting the transaction S_MEMORY_INSPECTOR for analysis and compare of memory snapshots.

·        Start Garbage Collector: Starting the garbage collectors