SAP MEMORY MANAGEMENT

SAP Memory Management

Virtual memory

It is collection of shared memory and local memory. Where shared memory is like paging, cache, swap etc.

The operating system determines if the allocated memory area resides in the physical memory or in the operating system swap space. Depending on the operation system, the maximum size of the virtual memory may vary between the size of the operating system swap space and the sum of physical memory and operating system swap/page space.

Local memory is associated with individual work processes.

Local work process memory is used for:

• ABAP load
• Data stack
• Buffer for database transfer
• Local roll area
• Local paging area

SAP Buffers in Shared Memory

Shared memory is associated with all the processes of one instance. SAP buffers contain global objects for all users and work processes, such as programs, and buffered table content.

Extended Memory in Shared Memory in Virtual Memory

Extended memory contains objects associated with individual users and their open transactions, such as variables, lists, and internal tables.

Heap memory:

Contains the same type of data as the extended memory and is used when extended memory is full. It is allocated and released on demand.None of the memory areas varies in size except SAP heap memory. Heap memory presents in the local memory.

SAP paging memory contains:

ABAP objects such as extracts and context-independent objects such as exports.

Roll memory

Contains the initial part of user contexts.

• User context:      
• Authorizations
• Set/get parameters
• Internal tables
• Report lists

Working:-

Working

First min roll memory get full and then  it goes to extended memory after that I will go to the again max roll memory and after that it will go to heap memory and if it also goes full it going to stop from here. Here the process will be stop and its status will be priv.

Note:-

For memory management we use the t codes ST02 it will going to show the buffer area and other memory.