TEvery work process contains a roll memory area that is located in the local process memory. It stores the initial user context that is swapped to the roll buffer when the process is changed (SAP process multiplexing). The roll buffer itself (don’t confuse it with the roll memory) is also referred to as the roll area and, like the extended memory, is a shared memory area. From SAP R/3 3.0 onward, the roll memory plays only a minor role, because the main part of the user context is directly stored in the extended memory and the access change is performed through the pointer.
Analyzing the SAP System
Having discussed the analysis of the hardware and operating system as well as of the Oracle database, we now turn to the analysis of the SAP system, or more precisely, the individual instances of the SAP system. The criteria that are relevant for the performance of an SAP instance can be divided into two main categories:n.
Memory of an SAP Instance
the importance of the SAP memory configuration (not of the SAP buffer) has decreased due to the technological progress in recent years. Above all, the enhancement of the main memory capacities, which also involves changing to the 64-bit technology, means the main memory is usually no longer the limiting factor of an SAP instance.
This shared memory is used by all work processes and is the most important memory area of an SAP instance. It contains all user contexts of the users that are logged in to the instance, with the exception of the small initial context that is being copied between roll memory and roll buffer
This memory area is a local memory that belongs to one work process. The work process type determines when the heap memory is used. It is used for dialog processes when the extended memory or at least the part of the extended memory that may be used by a single work process is entirely utilized. For nondialog processes, the local heap memory is used immediately after the roll memory, because here no process multiplexing is performed, and the extended memory is therefore reserved for the dialog processes..