em/use_sema_lock SAP Parameter attribute - Use OS semaphore for internal EM/ES locking

em/use_sema_lock is a SAP Parameter attribute which is used to control Use OS semaphore for internal EM/ES locking information. This is available within R/3 SAP systems depending on the version and release level.

Below is the standard documentation available and a few details of the attributes values .

em/use_sema_lock profile paramerter attributes

Parameter Name: em/use_sema_lock
Description: Use OS semaphore for internal EM/ES locking
Default Value: TRUE
Parameter Type ( See IF_PARAMETER_TYPES): Boolean(BOOL)
Restriction Values:
Parameter Unit:
Parameter Group: ExtMemory
CSN Component: BC-CST-MM
System-Wide parameter: No
Dynamic Parameter: No
Vector Parameter: No
Has Sub-Parameters: No
Check Function Exists: No

Parameter documentation

The parameter enables you to use a semaphore instead of a spinlock for process synchronization in extended memory administration. Although spinlocks are considerably faster than semaphores, they cause certain problems upon recovery from work process crashes. The parameter can also be used as a workaround if other problems with spinlocks occur.
Possible Values
TRUE - Operating system semaphore is used FALSE - Spinlock is used

See SAP Parameter Documentation for full SAP documentation for this profile parameter.