Overview of dynamic checkpoints
BMC Application Director for IMS uses checkpoints to suspend IMS BMP, DLI, and DBB batch jobs. Read-only jobs might not take checkpoints. For example, a batch report program does not update the database and is not required to take checkpoints.
The Dynamic Checkpoint feature repositions PCBs for IMS BMP,DLI, and DBB batch jobs at the location at the time of the checkpoint. Use this feature to suspend read-only BMP, DLI, or DBB jobs. When you enable Dynamic Checkpointing, Application Director dynamically issues an extended restart (XRST) call followed by a checkpoint (CHKP) call. The application program is then suspended following the CHKP call. When Application Director resumes the job, Application Director repositions the job using an extended restart (XRST) call.
In some cases, Application Director must wait for the read-only job to complete before BMC Database Director for IMS can finish the reorganization. When you specify Dynamic Checkpoints, Application Director:
- Takes a checkpoint and suspends the read-only jobs
- Repositions the PCBs for the jobs to the location at the time of the checkpoint
- Restrictions-for-dynamic-checkpoints Dynamic Checkpointing will not dynamically issue the XRST and CHKP calls in these cases.
- Dynamic-checkpointing-parameters
- Overriding-the-customization-parameters-after-customization-is-complete You can override the customization parameters after customization is complete.