What is "sdsf"

The System Display and Search Facility (SDSF) feature of IBM mainframes running z/OS allows users and administrators to be able to view and control various aspects of the mainframe's operation and system resources. Batch job output, status of running Unix processes, system information, workload scheduling, external device monitoring such as printers and initiators. SDSF is primarily used to access the batch and system log files and dumps.