Processes
When executing the planning run, the above steps are carried out by one or more of the following seven processes:
![](image055.gif)
Figure 7-44 illustrates the Snapshot Monitor Process logic under the Memory-based Planning Engine. Below is a detailed explanation of the logic.
1. Launch X Snapshot Workers via the Concurrent Manager, where X is the number of Snapshot Workers to launch, as defined by the profile option MRP:Snapshot Workers.
2. Begin Snapshot Preprocessing. These tasks include calculating repetitive planning periods for all the planned organizations, and relieving the MPS.
3. List the items that the planning engine will include in the current run. The plan-level option Included Items determines this list.
4. The Snapshot Monitor launches Snapshot Delete Workers to clean old snapshot and planning output from the tables.
5. Snapshot Workers select data from system tables, including work in process, inventory, purchasing, and bill of materials and write the data to flat files. Since the data is written to flat files, the deletes are not a prerequisite for this step.
6. Loader Workers load the flat files from step 5 into the MRP snapshot tables.
7. Once the workers complete the list of items for planning, lock the tables if Snapshot Lock Tables is set to Yes, then ask the Snapshot and Snapshot Workers to set transaction to read-only.
8. Loop until the workers complete.
9. Snapshot post-processing begins, which consists of cleanup activities and the execution of user-defined Snapshot Tasks.
After these steps, the Memory-based Planner performs the gross-to-net explosion and creates new supply orders.
If the user ran the Memory-based Planner without the Snapshot, the Memory-based Planning Engine launches Planner Delete Workers, which delete data from the planner output tables.
See Also
Phases of the Planning Process
Processes
Snapshot Tasks
Read Consistency
Interprocess Communication
Configuring the Memory-based Planning Engine
Enabling the Memory-based Planning Engine
Parallel Processing