When an organization runs the SAP ERP for several years, the discontinuation of materials is common and necessary practice. Usually, the deletion flag is set for discontinued materials or a status is set, in order to restrict some activities with this material.
The problem here is that when the deletion flag is set for a material, the planning file entry is not deleted and this material it is still considered by MRP during the planning run. As we can see on the picture below, there is nothing in the planning file to tell MRP that a deletion flag was set for this material.
MRP will read this material data from the database and only then find out that a deletion flag or status was set. A termination error message on the MRP List will be then triggered informing that the material was not planned.
If you have too many deleted materials, then they can be all read during the MRP run and the MRP performance can be improved if we avoid that.
The best way to proceed in this case is to set the MRP type ND for a material whenever setting the deletion flag or a status that forbid the MRP run.
When MRP type ND is set, the planning file entry will be deleted and this material will no longer be considered by MRP.
This procedure can be used to achieve a performance improvement in both MRP Live and Classic MRP and this is something very simple to do. A good way to check if you have too many deleted materials being considered by MRP is to use the report RMMDERRO to find MRP Lists with terminations and check if there are too many terminations for materials with deletion flag or a status that forbids the MRP run.