The System Display and Search Facility (SDSF) is a component of IBM's mainframeoperating system, z/OS, which allows users and administrators to view and control various aspects of the mainframe's operation and system resources using an interactive user interface. Information displayed in SDSF includes batch job output, Unix processes, scheduling environments, and the status of external devices such as printers and network lines, batch and system log files and dumps.
History
Originally written as a field developed program in 1979 by Carl Porter (IBM Sales Engineer), the "SDSF" acronym stood for "SYSLOG Display and Search Facility". The first version of the product allowed the user to browse and search the MVS system log.
The next iteration of the product included tabular displays that showed the various JES2 queues on the SPOOL (input, output, held and active jobs) and the acronym was altered to be "SPOOL Display and Search Facility" circa 1987. These displays are collectively known as the "queue panels" and they enable most mainframe users to view and manage their own jobs and output. SDSF became an official IBM program product in the 1980s and later on became an optional component of the operating system as its use was so widespread and important to the administration and operation of MVS.
The original design included retrieving information from JES2 and MVS control blocks and was sensitive to any changes to those structures which would require parts to be rebuilt. The product was supplied with source code throughout the 1980s and 1990s. JES2 eventually provided a subsystem interface (SSI) so that SDSF could remove its reliance on control block processing. Over time, a lot of the SDSF code was rewritten from assembler in PLX and this greatly reduced the amount of supplied source code.
With z/OS Release 1.9, SDSF supports a REXX interface, allowing batch programs to use SDSF facilities. This support includes stem variables containing SDSF-originated information.
Prior to z/OS Release 1.10, SDSF was only supported for use with JES2 and not JES3, although ISV products from Phoenix Software International and Tone Software were available with similar functionality for JES3.[citation needed] At and beyond z/OS Release 1.10, SDSF fully supports JES3, including some new commands (JDS and ODS) to display the data/sets and job output for JES3 jobs.
With the release of z/OS V1R13, SDSF came packed with some interesting features like cursor-sensitive sort or point-and-shoot sort and extensive support for open logs from Rexx and Java-programmed environments.
As SDSF was enhanced to display more operating system information, its acroynum was changed to mean "SYSTEM Display and Search Facility".
In 2015, IBM divested the development and support of SDSF to Rocket Software with a focus on re-invigoration of product functionality. A new server address space "SDSFAUX" was introduced as a SPE for z/OS 2.1 and 2.2 which was a strategic archiectural enhancement for future improvements to the product.
The main SDSF server was rewritten in z/OS 2.3 and the display manager code was rewritten in z/OS 2.4.
In z/OS 2.5, the legacy internal security mechanisms were deprecated in favour of using SAF resources protected by External Security Managers like RACF, ACF/2 and TopSecret.
In z/OS 3.2, SDSF added a python interface (pySDSF) to complement the existing REXX and Java interfaces.
SDSF is organized as a collection of panels where each panel displays information about a specific aspect of the mainframe's operations. There are over 100 various panels including:
LOG: To see the current log of system activity.
DA: "Display Active users/jobs" or running processes.
I: Input Queue - shows jobs waiting execution.
H: Jobs on HOLD - either waiting to be released into Input or Output or actual copies of job JCL (Job Control Language) or previously executed jobs.
ST: Displays current status of all jobs. Job list can be filtered using the PRE primary command.
PR: Displays printers.
INIT: Displays Initiators (areas where jobs execute or run).
O: Output Queue
LINE: Network Job Entry (NJE) Lines
SR: System Requests
MAS: Members in a MAS (Multiple Access Spool)
JC: Job Classes
PS: z/OS UNIX Processes
RES: WLM ( Workload Manager) Resources
ENC: Enclaves
SE: Scheduling Environments
NODE: NJE (Network Job Entry) Nodes
SO: Spool offload
SP: Spool volumes
RM: Resource monitor
CK: Health checker
APF: APF data sets
LNK: Link list data sets
PARM: Logical PARMLIB data sets
PROC: JES2 PROCLIB data sets
SDSF tabular panels provide the user with the ability to issue action characters against the one or more of the rows. Sometimes the action characters will take the user to another SDSF display, sometimes the action character will be translated internally to a MVS or JES command and issued on the user's behalf.
