Application Area
Memory Management
Short text
PROC Memory Quota
Parameter Description
Specifies the maximum process-local memory (HEAP, malloc) for data that is not user context specific that all work processes together can occupy.
Explanation:
There are two classes of process-local memory in SAP Memory Management:
- PRIV memory
- PROC memory
Both memory classes are fed by the heap memory of a work process. The difference between the two memory classes is that PRIV memory contains data from the user context, and is therefore bound to the current user session, whereas PROC memory is used for data that is required by each work process, regardless of user sessions. Because of this, the PROC memory consumption of the server does not vary greatly after the initial spike, whereas PRIV memory consumption can fluctuate greatly, depending on the memory requirement and the number of current user programs in use.
The name PRIV memory relates to the fact that a dialog work process switches to “PRIV mode” as soon as the application program currently being executed within it consumes private heap memory for its user context. The PRIV mode prevents the user context from being “rolled out” of the work process (for example, if the user is inactive). Therefore, the dialog process remains reserved for the user for the duration of the program execution.
Together with the quota for the PRIV memory (abap/heap_area_total), you can use this parameter to limit the total amount of process-local memory that can by allocated by a server instance, to avoid swap-space bottlenecks.
Parameter Unit
Megabytes
Default Value
Default value = 0 (that is, no explicit limit for PROC memory)
Who is permitted to make changes?
Customer
Operating System Restrictions
None
Database System Restrictions
None
Are other parameters affected or dependent?
See also parameter “abap/heap_area_total” for information about limiting PRIV memory consumption on a server-wide basis.
Values allowed
If you want to run other software on the server as well as AS ABAP, and want to keep memory free for this, we recommend setting the parameter to the maximum value that the PROC memory of the ABAP server can consume.
Example
A typical value for medium-sized to large-sized configurations would be 100 MB per work process. On a system with 100 GB swap space, 50 GB should be reserved for an SAP ABAP application server and 50 GB for non-SAP processes (for example, database).
To prevent the AS ABAP from consuming more than the total available swap space of 100 GB, you should set the following:
- abap/heap_area_total = 40 GB
- em/proc_max_size_mb = 10 GB
The remaining 50 GB are thus available for non-SAP processes.
