Meaning – A coupling facility is a piece of computer hardware or virtual machine, that coordinates multiple processors.
A coupling facility is used for the following functions –
Locking information that is shared among all attached systems
Cache information (such as for a data base) that is shared among all attached systems
Data list information that is shared among all attached systems
In order to achieve these functions, the coupling facility consists of the following structures – Lock, Cache and a List. Each of these structures consists of a dedicated portion of the coupling facility memory.
Software experts tend to use multiple structures of a specific kind, for their tasks.
Example of usage – “A coupling facility enables software on different systems in the Parallel Sysplex to share data with the assurance that the data will not be corrupted and will be consistent among all sharing users.”