Example: resubmitting a job for a checkpoint restart
This example shows the changes that you might make to JCL before you resubmit a job for checkpoint restart.
//J3412 JOB 386,SMITH,MSGLEVEL=1,RD=R,
// RESTART=(*,C0000002)
//SYSCHK DD DSNAME=C91468,DISP=OLD
//S1 EXEC PGM=MYPROG
//INDATA DD DSNAME=INVENT,UNIT=TAPE,DISP=OLD,
// VOLUME=SER=91468,LABEL=RETPD=14
//REPORT DD SYSOUT=A
//WORK DD DSNAME=T91468,DISP=(,,KEEP),
// UNIT=SYSDA,SPACE=(3000,(5000,500)),
// VOLUME=(PRIVATE,RETAIN,,6)
//DDCKPNT DD UNIT=TAPE,DISP=(MOD,KEEP,CATLG),
// DSNAME=C91468,LABEL=(,NL)
The following changes were made in the example above:
- The job name has been changed (from
J1234
toJ3412
) to distinguish the original job from the restarted job. - The
RESTART
parameter has been added to theJOB
statement, and indicates that restart is to begin with the first step at the checkpoint entry namedC0000002
. - The
DD
statementDDCKPNT
was originally assigned a conditional disposition ofCATLG
for the checkpoint data set:- If the step terminated normally in the previous run of the job,
the data set was kept. In that case, the
SYSCHK DD
statement must contain all of the information necessary for retrieving the checkpoint data set. - If the job abnormally terminated, the data set was cataloged.
In that case, the only parameters required on the
SYSCHK DD
statement areDSNAME
andDISP
as shown.
- If the step terminated normally in the previous run of the job,
the data set was kept. In that case, the
If a checkpoint is taken in a job that is running when V=R
is
specified, the job cannot be restarted until adequate nonpageable
dynamic storage becomes available.