Memory Management

[former_member105243]

Hello Team,

Please help in clarifying a query regarding the memory management (extended/heap) in SAP environment.

em/initial_size_MB - Total extended memory assigned to the system

ztta/roll_extension - User quota for extended memory

abap/heap_area_dia - Work process quota for dialog task type

abap/heap_area_nondia -  Work process quota for non-dialog task type

abap/heap_area_total - Total heap area assigned to the sytem

My query is mainly regarding the parameter - "ztta/roll_extension". What exactly does user quota mean ?

Lets say - ztta/roll_extension = 2 GB and the user in question is Mr. X. Does this mean that X can allocate only maximum of 2 GB extended memory at any point of time.

OR, lets say user X is running some activities in the system, may be in different SAP window/session and currently 6 (or so) dialog work process is being occupied by his work. Does this mean that each of the workprocess gets to occupy 2 GB of extended memory or the sum of EM ocuupied by these 6 work process in total cannot exceed 2 GB at any point of time?

Cheers,

Pankaj Kedia

[isaias_freitas]

Hello,

Does this mean that each of the workprocess gets to occupy 2 GB of extended memory

Correct. Each work process would be handling a distinct "user context" from the user. Thus, each work process can allocate up to 2GB of the Extended Memory area.

Regards,

Isaías

[former_member105243]

Hello Isaias,

Thank you for clarifying that. Actually I read somewhere regarding these parameters and it was quite misleading (See the screenshot attahed).

For ztta/roll_extension it says "User quota for extended memory"

whereas,

For abap/heap_area_dia (nondia) it says "Limit of heap memory one work process can allocate"

But as you mentioned, even for the ztta/roll_extension it is specific to work process.

BR,

Pankaj

[former_member105243]

Hello Yuksel,

Thank you for your help.

Can you please help in clarifying what exactly a user context means ?

If a user opens lets say 6 sessions in the system - does this means 6 contexts ?

Or, lets say a user is running some background job which in turn creates (lets say) 20 child processess and hence 20 work process are occupied for that user in the same session. What will be the EM in this case ?

Cheers,

Pankaj Kedia

[yakcinar]

Hello Pankaj,

Can you check the below discussion, please?

I tried to explain memory management there.

Regards,

Yuksel AKCINAR

[yakcinar]

Hello Pankaj,

You can see details of user context in below discussion.

when does the user context contains user relate... | SCN

Regards,

Yuksel AKCINAR

[yakcinar]

Hello Pankaj,

No this parameter is note the limit at any point of time for a user.

This ztta/roll_extension parameter is the value specifies the amount of memory that one user context can allocate from the SAP extended memory. This value is valid for all types of work processes.

A user can allocate  (ztta/roll_extension + abap/heap_area_dia) amount at maximum.

These links can help you to clarify.

SAP Memory Management (BC-CST-MM) - SAP Library

88416 - Zero administration memory management for the ABAP server

ztta/roll_extension: Limit for Extended Memory - SAP Memory Management (BC-CST-MM) - SAP Library 

Regards,

Yuksel AKCINAR