Solution : https://service.sap.com/sap/support/notes/153909 (SAP Service marketplace login required)
Key words : 
prerequisites solution solutions check list, infocube               ==> infocube performance==> check indexes, alerts inthe alert monitor, ==> change standard secondary index, check data consistency, additional key words, dbs/ora/array_buf_size = 1000000 ------------------------------------------------------------------------ 7, + display +    index function, report    '/sapapo/rmdp_icube_perform', transaction se11 + table
Related Notes : 
       
| 183490 | |
| 180605 | Oracle database parameter settings for BW | 
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| 157629 | |
| 157358 | |
| 153910 | |
| 150302 | |
| 146162 |