Coding the DD Statement for a Checkpoint Data Set

The DD statement for the checkpoint data set must define the data set in the usual way. The publication z/OS MVS JCL Reference contains detailed information about coding the DD statement.

Coding the DCB for a Checkpoint Data Set describes certain DCB parameters that you can code on the DD statement.

The only restrictions on the DD statement are:

A checkpoint data set cannot be concatenated, because it is an output data set.
The UNIT parameter must specify a tape or direct access device supported by BSAM or BPAM. The device can be specified by referring to a specific device, a device type, or a group of devices.
If direct access is specified, the device cannot be shared with another processor, unless your installation has special procedures in place to control the use of checkpoints on shared DASD. See z/OS DFSMS Using Data Sets for specific details. To avoid allocating to a shared DASD, a special generic device name should be generated at system definition time to include a nonshared DASD of a single device type.
DEFER should not be coded in the DD statement.
DISP=SHR cannot be specified.
Secondary space allocation may be requested by the increment subparameter (see Notes on the DD Statement). The increment subparameter must specify at least enough space to contain two complete checkpoint entries. For information about calculating the length of the checkpoint entry see Storage Estimates for Checkpoint Data Sets.
The LABEL parameter of the DD statement describes the labels of a data set on magnetic tape. For a checkpoint data set, you must specify only IBM® standard labels (SL or SUL). Nonstandard labels (NSL), no labels (NL), or International Organization for Standardization/American National Standards Institute (ISO/ANSI) labels (AL or AUL) cannot be specified for a checkpoint data set. If the label type is not specified, the operating system assumes that the data set has IBM standard labels (SL).
OPTCD=Q cannot be specified as a DCB subparameter.
CHKPT=EOV is ignored (checkpoint resets the value in the JFCB).
The RLSE subparameter of the SPACE parameter cannot be used on the DD statement for a checkpoint data set.
A checkpoint data set cannot be an extended format data set, a PDSE file, or an HFS file.