Defining Checkpoint Data Sets

The values specified on this statement are initial values only. If any are changed after initialization by operator command, or by use of the checkpoint reconfiguration dialog, many of these initial values will be ignored on a hot or warm start as shown in the following list. However, JES2 honors all new values if you specify the RECONFIG option.

Use the RECONFIG option with caution, because severe queue damage can result if you use the incorrect checkpoint data set(s) on a restart. (See z/OS JES2 Initialization and Tuning Guide for further explanation of the start options.)

Note that JES2:
  • Ignores CKPT1= and CKPT2= specifications on a hot start.
  • Ignores NEWCKPT1= and NEWCKPT2= specifications except on a cold start or if RECONFIG is added to the warm start command.
  • Ignores MODE= and LOGSIZE= specifications on a warm start unless RECONFIG is added to the warm start command.
  • Preserves respecification of NEWCKPT1= and NEWCKPT2= by $T across a warm start unless RECONFIG is also added to the warm start command.