Solution : https://service.sap.com/sap/support/notes/184133 (SAP Service marketplace login required)
Key words : 
operating system   /oracle/<sapsid>  /oracle/stage   /tmp-------------------------------------------------------------------aix                  900 mb        600 mb           50 mbdigital unix        1000 mb        800 mb           50 mbhp-ux                1000 mb        600 mb           50 mbreliantunix          900 mb        700 mb           50 mbsolaris              700 mb        700 mb          50 mb---------------------------------------------------------------------iii/ correction, oracle upgradei/ important general remarks---------------------------------------------------------------------ii/ required disk space-------------------------<d019144 25/mar/99>-------------------------, /    important general remarks     ii/    required disk space, upgrade     iii/  correction, operating system, apply hp-ux patch mentioned, /oracle/stage/stage_806/lib2, oracle migration------------------------<c5001094 25/mar/99>-------------------------symptom, /oracle/stage/stage_806/lib 2, setenv term 97801this terminal environment
Related Notes : 
       
| 388635 | UPGRADE.ORA terminates on HP-UX 11.11 | 
| 319916 | 64-bit ORACLE 8.0.6 on HP-UX only with HP-UX patch PHSS_2194 | 
| 303238 | Inst. the ORACLE Client Software 8.0.x for 4.6C/46D | 
| 215917 | Easy change from Rule to Cost-Based Optimizer | 
| 210707 | |
| 170989 | Poor performance under Oracle 8044, 805*, 8.0.6 | 
| 12741 | Current versions of BR*Tools and SAPDBA |