Solution : https://service.sap.com/sap/support/notes/1117785 (SAP Service marketplace login required)
Key words : 
sap service market place, sap software center, applying support packages, oracle                    < oracle 32 bit>, <oracle 64 bit>                      < oracle 10, oracle database, oracle 10g, executing reports, considerable deterioration, runtime performance
Related Notes : 
       
| 838725 | Oracle dictionary statistics and system statistics | 
| 830576 | Parameter recommendations for Oracle 10g |