Solution : https://service.sap.com/sap/support/notes/1236753 (SAP Service marketplace login required)
Key words : 
program error solution implement, symptom performance issue observed, attached correction instruction, fetching partner data, optimize performance, partner interface, terms partner, /sapsrm/cl_pdo_do_partner_base, get_header_partner reason, prerequisites
Related Notes : 
       
| 1331726 | Performance in items display in Rfx response | 
| 1255376 | Performance Issues in RFx and RFx Response | 
| 1255374 | Performance Issues in RFx and RFx Response | 
| 1254485 | Performance Issues in RFx and RFx Response | 
| 1169088 | SRM 6.0 Performance Guide |