$T CKPTSPACE - Set the checkpoint space

Function

To modify information about the amount of space in the checkpoint.

Syntax

Read syntax diagramSkip visual syntax diagram$TCKPTSPACE ,BERTNUM=bertnum,BERTWARN=bertwarn,CDINUM=cdinum

Parameters

BERTNUM=bertnum
The number (200–2,500,000) of BERT (Block Extent Reuse Table) entries defined in the checkpoint. The lower limit when decreasing this value is based on the number of JOEs and JQEs defined on the system. In addition, you cannot decrease it below the number of BERTs that are in use. For example, if BERT 23176 is the highest BERT in use, then 23177 is the lowest you can reduce BERTNUM to. This is true even if 23175 is not currently in use. Likewise, you cannot increase the BERTNUM parameter to a value below the number of BERTs that are defined on the system. You must specify a BERTNUM value that is between the system-calculated minimum and the system-defined maximum. Specifying a value that is too low results in an HASP003 message with the lowest valid value displayed.
Note: Use this parameter to increase the limit for the JNUM resource that is reported on the HASP050 message.
BERTWARN=bertwarn
The threshold of BERT utilization at which the $HASP050 message should be issued. The valid range is 1 to 100.
Start of changeCDINUM=cdinumEnd of change
Start of changeThe number (16-65536) of the configuration directory entries (CDIs) defined in the JES2 checkpoint. The default is 128. The number can be increased (if JES2 checkpoint size is sufficient for expansion) or decreased. The number cannot be decreased below current number of CDIs in use (CDINUM minus CDIFREE as displayed by $D CKPTSPACE command). To decrease the number, all CDI entries above the specified number must be free, even if CDIFREE shows sufficient number of unused CDIs.End of change

Authority Required

This command requires system authority. The description of the $T RDRnn command explains how to ensure that the authority of the appropriate MVS™ system command group is assigned.

This command requires control security access authority. For a description of assigning command input authority, see z/OS JES2 Initialization and Tuning Guide.

Scope

MAS-wide. The command has an effect across the entire MAS.

Messages

The $HASP852 message displays the current values of all the parameters on the CKPTSPACE initialization statement.

Example

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$t ckptspace,bertnum=650    
                             
          $HASP852 CKPTSPACE                                      
$HASP852 CKPTSPACE  BERTNUM=650,BERTFREE=497,BERTWARN=80,         
$HASP852            CKPT1=(CAPACITY=1788,UNUSED=1431,             
$HASP852            TRACKS=150),CKPT2=(CAPACITY=1788,             
$HASP852            UNUSED=1431,TRACKS=150),CDI=(CDINUM=128,      
$HASP852            CDIFREE=128,CDTSIZE=524264,CDTFREE=524264)
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