Note 117907 - Display of SAP Memory usage in SM04 and ST02

Summary

Symptom
The different displays for the memory consumption in transaction ST02 ("Tune Summary", "SAP Memory") and transaction SM04 ("User List" -> "Goto -> Memory") cause confusion.
Other terms
Memory management, extended memory, roll area, roll, roll memory, SM04, ST02
Reason and Prerequisites
See the solution.
Solution
The two transactions display the memory consumption from different points of view; furthermore, different terms are used for the same thing.
When you call SM04 and choose "Goto -> Memory", the system displays the memory that is allocated for each user; the bottom line specifies the total memory requirement for all users. The following memory types are available (for more information, see the online documentation for the memory management):
Roll * Page * Mem(Total) * Mem(Priv.)
The corresponding terms in transaction ST02 are:
Roll area * Paging area * Extended Memory * Heap Memory
The usual assumption that the total of all users of one memory type (for example, extended memory) must be identical with the currently used value in transaction ST02 (with converted units) is incorrect. This is due to the fact that the two overviews do not have the same goal.

• In transaction ST02, you consider the memory consumption from the resources point of view (gross): How much memory is being used? The extended memory is, for example, always output in 1MB blocks (thus, it increases in jumps); for the roll memory, a certain portion is used for management data.

• Transaction SM04 displays how much memory the current user requirements allocate (net). Management data is not included. Therefore, a steady growth is displayed when you repeatedly refresh.

For this reason, the corresponding figures (for example the total of "Mem(Total)" in transaction SM04 and "Extended Memory" - "Current use" in transaction ST02) do not have to be identical. Furthermore, it is not mandatory that one of the figures always has a lower value than the other figure. These are simply different views for the available memory.

Header Data

Release Status:	Released for Customer
Released on:	13.01.2009  16:51:01
Master Language:	German
Priority:	Recommendations/additional info
Category:	Consulting
Primary Component:	BC-CST-MM Memory Management

Affected Releases