Solution : https://service.sap.com/sap/support/notes/300177 (SAP Service marketplace login required)
Key words : 
directory /usr/sap/put/exe, service entry sapdb2<sid> -, downward-compatible kernel, expect performance improvements, ordinary network log, minimum table size, 'rebuild index' utility, 6d-dbsl library, patch levels listed, individual upgrade phases 7
Related Notes : 
       
| 504959 | Upgrade Assistant on z/OS | 
| 306908 | DB2/390: Primary index created without CLUSTER | 
| 302309 | Additions Workplace Server Upgrade to Rel. 2.10/2.11 | 
| 81737 | DB2-z/OS: APAR List |