Application Server with over 50 Users (iSeries)

The correct configuration for the memory management system in a large SAP NetWeaver Application Server depends on several factors. We cannot, therefore, give any recommendations for standard configuration. However, you can calculate your own approximate values by referring to the information in this section and in the other sections that are referred to.

To determine the required resources for the host system, contact the SAP Competence Center of your hardware partner. Then you can configure the SAP NetWeaver Application Server by setting the memory management parameters in the SAP system profile.

Main and Unprotected Storage on the Host System


SAP Recommendation

Free auxiliary storage

Minimum: The greater of the following two values:

·         6 GB

·         Three times the main memory

In either case, this must be greater than the sum of:

·         The required unprotected storage (can be estimated using the program rspfpar, see Additional Swap Space Requirements).

·         The memory requirements of the operating system

·         To be on the safe side, at least 2 GB of free ASP when executing the operation

Main storage


Central system with all services, no database: 180 MB plus 5.7 MB per active user or at least 512 MB

With database: Add 150 MB plus 0.3 MB per active user

Application server: 120 MB plus 5.3 MB per active user

An increase in storage improves performance. Please also contact your hardware partner or the SAP Competence Center of your hardware partner.

Profile Parameters

For information about how the various parameters are used, see Profile Parameters of Memory Management.


Recommended Value

abap/heaplimit: Work Process Restart

40000000 (40 mil. bytes)

abap/heap_area_dia: Heap Memory Limit for Dialog Work Processes

2000000000 (2 GB)

abap/heap_area_nondia: Heap Memory Limit for Non-Dialog Work Processes

See parameter documentation.

abap/heap_area_total: Heap Memory Limit

2000000000 (2 GB); see parameter documentation.

em/initial_size_MB: Extended Memory Pool Size

5 MB per active user + 1.5 MB per user; Minimum 1024 MB

em/stat_log_size_MB: Statistics - User Context Size


em/stat_log_timeout: Statistics - User Context Size


rdisp/ROLL_MAXFS: Maximum Roll File Size


rdisp/ROLL_SHM: Roll Buffer Size


rdisp/PG_MAXFS: Maximum Size of the SAP Paging File

32768 (The same value as rdisp/PG_SHM)

rdisp/PG_SHM: Paging Buffer Size


ztta/roll_area: Roll Area

Set automatically

ztta/roll_first: Initial Allocation Size from the Roll Area

Set automatically

ztta/roll_extension: Extended Memory Limit

20000000000 (2 GB)

The settings listed here are recommended base values that you may, however, have to change when you monitor or optimize your SAP system. For more information, see Monitoring the Memory Management System and Profile Parameters of Memory Management.

Check the changes to the system profiles using the program rspfpar. For more information, see Operating System and Hardware Prerequisites.