That Redbook also has a section on tuning storage on AIX (section 3.4). It covers the parameters used for hdisks erformance: queue_depth, max_transfer and max_coalesce. It then gives an explanation on the Fibre Channel Adapters configuration, where the num_cmd_elems and max_xfer_size are worth a look.
These descriptions and recommendations are not specific to DB2 systems. There's something in it for anyone connecting AIX to the SAN.
Once again, you can get to the Redbook here. See two sections in particular:
- Section 3.4 Tuning storage on AIX; and
- Section 7.4 System Planning.