Solution : https://service.sap.com/sap/support/notes/420605 (SAP Service marketplace login required)
Key words : 
prerequisites composite sap note solution collection, inactive order items cancelled 10    380703 backorder processing, displaying performance results 19    459748 19    481306 15    421716 backorder processing, posting      609435 composite sap note, sp    note     text      504620 deletion, / cancelld confirmtn 10    384187 backorder processing, unchecked status 10    380431 backorder processing, open quantity additional prerequisite, -time delivery 11    395906 backorder processing, backorder processing 21    511608 21    513869 21    514777 21    517698 21    517897 21    527532 20    490685 backorder processing
Related Notes : 
       
| 609435 | Composite SAP note: Performance in backorder processing | 
| 504620 | Deletion of R/3 data that are no longer required in APO | 
| 490685 | Backorder processing: performance update | 
| 486628 | Backorder processing: Displaying performance results | 
| 421716 | Backorder proc.: Writing of the queue waits for alerts | 
| 421657 | Backorder processing: runtime display | 
| 421358 | Backorder proc.: Deletion of alerts takes a long time | 
| 421030 | Backorder processing: Long runtimes for update | 
| 420606 | Collective SAP Note for GATP performance in APO 3.0A | 
| 396589 | Backorder processing: Filter with one-time delivery | 
| 395906 | Backorder processing: Incorrect sub-item dates | 
| 388058 | BOP: Reading data takes a long time | 
| 385810 | Backorder processing: Results not updated | 
| 385599 | Backorder processing: Planning orders not deleted | 
| 385524 | Backorder processing: delivery time-spot is missing | 
| 385472 | Backordr procss.:do not transfer items w/ cancelld confirmtn | 
| 384187 | Backorder processing: Planned orders not saved | 
| 383514 | Backorder processing: Incomplete transfer | 
| 382050 | Deleting (SD) orders: database index is inactive | 
| 381190 | Backorder processing:Inactive order items cancelled | 
| 380703 | Backorder processing: Documents with unchecked status | 
| 380431 | Backorder processing: Order items without open quantity | 
| 375193 | Backorder processing: Composite SAP note on posting |