We have been receiving the following error messages in our alert log:

ORA-1650 unable to extend rollback segment BIG_ROLLBACK by 640 in tablespace RBSBIG
Failure to extend rollback segment 2 because of 1650 condition

v$rollstat info on segment #2 is:

extents rssize optsize curext shrink wrap extends
139 728752128 20971520 138 19 332 311

initial extent and next extent are both 5242880.

So there are basically 3 options: have the developer write more commits in the program, defrag the RBS tablespace (how can I tell if its defragmented?), or add more size to the RBS tablespace. But how do I know which is the best option?

I really don't know exactly what else I need to check/monitor with this rollback segment. Does anybody have any suggestions?