9c3a3d9f_Basic_CLIST_commands__Its_USE
[S.No] 61 [Clist Command] &SYSSRV [Its USE] 
The &SYSSRV variable provides the number of service units used during the current TSO session. Service units consist of CPU time, I/Os, and main storage occupancy values and are used within MVS to manage work flow.
Basic CLIST commands
Its USE