Determining the new checkpoint size

The $HASP537 message at JES2 initialization displays the number of 4K records needed for the checkpoint data set. This number does not allow for any increase to these parameters nor for expansion by the $ACTIVATE command which is necessary to enable new functions at the current JES2 level.

To determine how much checkpoint space to allocate to allow the $ACTIVATE command you can issue $DACTIVATE and the response will display the number of 4K pages needed.

To determine how much checkpoint space to allocate for a new release or for expansion:

Cold start a secondary JES2 specifying the maximum values to be supported for the specifications identified in Table 1. You should use values for the specifications that reflect what you might need in the future. If you want values for z2 mode, be sure to specify PARM=UNACT since otherwise COLD start assumes you will be in z11 mode.
The $HASP537 message will display the number of 4K records required for the checkpoint data set.

Table 1. JES2 parameters affecting checkpoint size
Description	Initialization Parameter	Default
Number of Spool Volumes	SPOOLDEF SPOOLNUM=	32
Number of Track Groups on Spool	SPOOLDEF TGSPACE=(MAX=)	16288
Size of Job Queue	JOBDEF JOBNUM=	1000
Size of Job Output Queue	OUTDEF JOENUM=	2.5 x JOBNUM
Size of Change Log on Checkpoint	CKPTDEF LOGSIZE=	1 (if MODE=DUPLEX) 1 to 9 (if MODE=DUAL)
Size of Block Extension Reuse Table	CKPTSPACE BERTNUM=	Greater of the two values: (JOBNUM + JOENUM/4 + 100) or 399
Number of NJE nodes	NJEDEF NODENUM=	1

If you want to over-allocate checkpoint for expansion but do not want to determine specific values, consider allocating 2 to 3 times your current checkpoint space.

If you need more space, you can use the checkpoint reconfiguration dialog to move the checkpoints to larger data sets or structures.

Use the $D CKPTSPACE command to determine the size of the checkpoint and amount of free space in the current checkpoints. Use the $D ACTIVATE command to see if $ACTIVATE has been issued.