In OATM data is placed according to usage. Right? So your data intensive
tables in tablespace, stale data in another tabelspace etc.. But one
question is if you have two tables that are heavily used (lot of inserts or
lot of selects and could happen when two modules accessing different tables
are running a concurrent program or could be just a bad select statement).
In this case you are probably creating hotspots in an OATM model whereas in
the old model, they would be accessed from a different datafile.