Memory related query

[Former Member]

Hello Gurus,

I want to analyse an SAP system if it is using the available memory in an optimised manner

From your past experiences , can you let me know the thumb rule to assess?

Say for Ex , I have the below memory assigned to my host

             total       used       free     shared    buffers     cached

Mem:          2019       1060        958          0          0         47

-/+ buffers/cache:       1013       1006

Swap:           19          0         19

Total:        2039       1060        978

and I guess we can have 60% allocated to SAP and 30% for the database.

Can you on a high level let me know , what are the main parameters which I need to check in order to make sure that my SAP server is properly using the allocated memory.

My DB size is 15 TB.

Basically i want to know the most important oracle and sap parameters to consider.

Thanks,

Sowmya

[Sriram2009 · Accepted solution]

Hi Sowmya

1. Is this SAP CI & DI on single system? could you share the  SAP & OS/DB version details?

2. Yes, You have to use the SAP Application + OS for 70 % & DB 30 % of over all memory

3. During the peak time are you facing slowness or any other issues?

Regards

SS

[Former Member · Accepted solution]

Hello Sriram,

I am not facing any performance issue. I need to check in all the servers if the virutal memory assigned to the server is used optimally or it is wasted. 

I basically have to check if one more SAP server is added to that server, will there be any issues.

it is only CI . there is no CI .

So If I want to calculate how much memory approximately is going to the current SAP system from the server and to the data base what are the parameters to consider?

For Ex : PGA+SGA for database. any other parameters ?

For sap : roll area, initial size , EM and heap quotas . Are these enough?

Thanks,

Sowmya

[Sriram2009 · Accepted solution]

Hi Sowmya.

1. For over all usage of CPU, main memory,Maximum swap  in transaction code based on SAP system version ST06/ST06N/OS07N, Refer the link

About SAPOSCOL - Netweaver Technology - SCN Wiki

2. As already said by Manjunath using the ST02, you can analysis SAP memory/buffers area,

Refer the link  http://www.sap-perf.ca/run-sap-st02-memory-monitor/

Regards

SS

[former_member230159]

Hi,

You can refer these notes :

117907 - Display of SAP Memory usage in SM04 and ST02

2085980 - New features in memory management as of Kernel Release 7.40

Also please have a look at

SAP Memory Management System - Application Server Infrastructure - SCN Wiki

Hope this info helps !!

Do let us know your further queries

best regards

Manjunath Hanmantgad

[former_member230159]

Hi Sowmya,

You can check the memory usage in tcode /ST02 . Here you can see how much paging , EM is being used. In here you can see memory related parameters under SAP memory tab.

Also you can run sappfpar command to check.

As such there are many parameters that needs to be considered based on the kernel version (7.2X , 7.4X) and OS related, these might include extended memory , paging , heap related parameters.

Hope this helps.

Regards