Profiles 
Purpose
SAP profiles are operating system files that contain instance configuration information. SAP systems can consist of one or more instances. Individual configuration parameters can be customized to the requirements of each instance. These individual parameters allow you to configure:
· The runtime environment of the instance (resources such as main memory size, shared memory, roll size)
· Which services the instance itself provides (work processes)
· Where other services can be found (database host)
Features
The profile file is structured as follows:
# This is a comment in an SAP profile:
Parametername1 = Value1
Parametername2 = Value2
Parameter names that logically belong together have a common root. For example, the root of parameters that control the dispatcher within an application server is: rdisp/.
The parameter rdisp/wp_non_dia specifies how many dialog work processes are started by the dispatcher.
The SAP profiles are stored in a special file directory. This directory can be made accessible from all hosts, depending on current requirements.
UNIX systems:/usr/sap/<SID>/SYS/profile
Microsoft Windows NT systems: \\<SAPGLOBALHOST>\sapmnt\<SID>\sys\profile\
(<SID> = SAP system name and <SAPGLOBALHOST> = name of the NT machine on which the global profile directory is physically located)
All host computers in an SAP System can access these profiles. It is possible for multiple instances to use a single profile simultaneously. Separate profiles are not required for each instance.
Use the Computing Center Management System (CCMS) to maintain configuration profiles. You should therefore not edit the active profiles directly at operating system level.
See also:
Substitute Variables in Profile Values
Checking, Saving, and Activating Profiles