Resolving dependencies between operations
The rules used by the daily planning process for resolving external dependencies between operations are:
- Case A:
- The successor operation has no input arrival time specified. An external dependency to an operation in the predecessor occurrence is created if the input arrival time of the predecessor occurrence is earlier than, or equal to, the input arrival time of the successor occurrence.
- Case B:
- The successor operation has input arrival time specified. An external dependency to an operation in the predecessor occurrence is created if the input arrival time of the predecessor occurrence is earlier than, or equal to, the input arrival time of the successor operation.
When the current plan is extended, dependencies between new occurrences
and existing occurrences that are carried forward from the old plan
are resolved only if the dependency is in the long-term plan when
the current plan is extended. An occurrence added by the daily planning
process from the long-term plan will not be made a successor to an
occurrence added by automatic job recovery, PIF, ETT, or the MCP panel,
even if normal dependency criteria are met. For example, consider
this case:
- Application A is run daily. It has an input arrival time of 09:00 and contains one operation, A1. Application A exists in the long-term plan.
- Application B is run daily. It has an input arrival time of 16:00 and contains one operation, B1. B1 has A1 defined as an external predecessor in the application description database. Application B exists in the long-term plan.
- An occurrence of application A is added to the current plan from the MCP panel at 12:00. The occurrence input arrival is 12:00.
- The daily planning batch job is run at 15:00 to extend the current plan. Application B is added to the current plan by daily planning and is given a dependency on the 09:00 occurrence of application A. The external dependency is not resolved to the 12:00 occurrence of application A.
- If another occurrence of application B is added to the current plan at 16:15 using the MCP panel, with an input arrival time of 16:15, the external dependency is resolved on the 12:00 occurrence of application A.
If you need to change or add dependencies in the current plan, use the MODIFY CURRENT PLAN panel, which is described in Changing and adding dependencies.