SETSMS command

Use the SETSMS command when the Storage Management Subsystem (SMS) is active (running) to change a subset of SMS parameters from the console without changing the active IGDSMSxx member of SYS1.PARMLIB. Changes that you make with the SETSMS command persist until a subsequent SETSMS command is run for the same option, until the next SET SMS=xx command is run, or until the next system IPL.

Use the SETSMS command to:

For more information about the ACDS, SCDS, and COMMDS data sets, see z/OS DFSMSdfp Storage Administration and z/OS DFSMSdfp Diagnosis.

If you are not sure about the differences between SET SMS and SETSMS, see Table 1.

Table 1. Comparison of SET SMS with SETSMS
Difference SET SMS Command SETSMS Command
When and how to use the command Initializes SMS parameters and starts SMS if it has been defined but not started at IPL time. Changes SMS parameters if SMS is already running. Changes SMS parameters only when SMS is running.
Where the parameters are entered In the IGDSMSxx member of SYS1.PARMLIB. At the console.
What default values are available Default values are used for unspecified parameters except for BLOCKTOKENSIZE. If you omit BLOCKTOKENSIZE, the previous value in effect remains in effect. In z/OS® 1.7, the original value of BLOCKTOKENSIZE is REQUIRE and in z/OS 1.8 and later the original value of BLOCKTOKENSIZE is NOREQUIRE. No default values. Unspecified parameters remain unchanged.

Some combinations of SETSMS parameters are not valid. Table 2 shows these incorrect combinations.

Requirement: The SCDS is a required parameter if the ACDS does not contain a valid configuration.

Note: The SCDS is a required parameter if the ACDS does not contain a valid configuration.
Table 2. Incorrect Combinations of SETSMS Parameters
Parameter ACDS SCDS COMMDS SAVEACDS
ACDS N/A   Not Valid Not Valid
SCDS   N/A Not Valid Not Valid
COMMDS Not Valid Not Valid N/A Not Valid
SAVEACDS Not Valid Not Valid Not Valid N/A