Setting the Profile Parameters (iSeries)

Use

The optimum parameter settings are dependent on:

·        Available hardware resources (main memory and free auxiliary storage)

·        System load, that is average or maximum number of active users on an application server

Procedure

The following table is a guide for setting the profile parameters for the iSeries platform:

Parameter

Unit

Default Value

Recommendation

Comment

abap/heaplimit: Work Process Restart

Bytes

40000000

(40 MB)

40 MB

ztta/roll extension: Extended Memory Limit

Bytes

2 GB

Possibly lower depending on application

abap/heap_area_dia: Heap Memory Limit for Dialog Work Processes

Bytes

2 GB

2 GB

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

Bytes

2 GB

2 GB

abap/heap_area_total: Heap Memory Limit

Bytes

2 GB

2 GB

You can use the operating system monitor (ST06) to monitor physical storage and ASP usage.

Allocated unprotected temporary storage includes the allocated memory of:

·         All SAP system instances

·         Database buffers and processes

·         Operating system

You can look at this in detail using transaction ST02 ® Detail analysis ® Storage.

em/initial_size_MB: Extended Memory Pool Size

MB

4092

Minimum 64 MB

rdisp/ROLL_SHM: Roll Buffer Size

8 KB blocks

16384

16384

Do not define a value higher than 12500 (100 MB) unless the CCMS Tune Summary (Transaction ST02) under Monitoring the Memory Management System states that a larger roll buffer is required.

Absolute upper limit: 250000 blocks (2 GB) for special applications

rdisp/ROLL_MAXFS: Maximum Roll File Size

8 KB blocks

32768

32768

Absolute upper limit: 250000 blocks (2 GB) for special applications

rdisp/PG_SHM: Paging Buffer Size

8 KB blocks

32768

32768
(the same value as
rdisp/PG_MAXFS)

Absolute upper limit: 250000 blocks (2 GB) for special applications

rdisp/PG_MAXFS: Maximum Size of the SAP Paging File

8 KB blocks

32768

32768

Absolute upper limit: 250000 blocks (2 GB) for special applications

ztta/roll_first: Initial Allocation Size from the Roll Area

Bytes

1 byte

1 byte

This value is set automatically and cannot be changed.

ztta/roll_area: Roll Area

Bytes

3 MB

3 MB

This value is set automatically and cannot be changed.

em/blocksize_KB: Segment Size for the Extended Memory

KB

4096

(4 MB)

4096

(4 MB)


Do not change the default value.