Solution : https://service.sap.com/sap/support/notes/632427 (SAP Service marketplace login required)
Key words : 
optimizer_mode                      chooseoptimizer_percent_parallel          100parallel_broadcast_enabled          trueparallel_execution_message_size     16384parallel_max_servers                # cpus 8optimizer_max_permutations          2000parallel_threads_per_cpu            1processes                          >, db_file_multiblock_read_countlog_checkpoint_interval             0log_archive_start                  truelog_buffer                          1048576log_checkpoint_timeout              0log_checkpoints_to_alert            truemax_dump_file_size                  20000, ensure error-free database operation, numerous sap/oracle customer systems, cpus 2db_block_size                      8192db_file_multiblock_read_count       32distributed_transactions            0, hash_area_size                      sort_area_size 2hash_join_enabled                  truehash_multiblock_io_count, note 601668 10191                              note 128221 10028                              note 596420 10027                              note 596420fast_start_io_target                0, profile >log_simultaneous_copies            obsolete - delete, checks oracle database parameters, set oracle database parameters
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| 834343 | Oracle 9.2 Platform Support for Async IO | 
| 632556 | Oracle 9.2.0.* database parameterization for BW | 
| 567745 | Composite note BW 3.x performance: DB-specific setting | 
| 378509 | Oracle DB parameter setting for APO | 
| 180605 | Oracle database parameter settings for BW |