Originally posted by grjohnson

And yet 10 Rollback segments were onlined *scratches head*. I'm not sure how 9.2.0. arrived at on-lining 10 segments.

Undo Segment 1 Onlined
Undo Segment 2 Onlined
Undo Segment 3 Onlined
Undo Segment 4 Onlined
Undo Segment 5 Onlined
Undo Segment 6 Onlined
Undo Segment 7 Onlined
Undo Segment 8 Onlined
Undo Segment 9 Onlined
Undo Segment 10 Onlined
I think that initial creation of 10 undo segments is by default...
It doesn't matter how big or small ur database is or what values you have set in
SESSIONS = 170
TRANSACTIONS = 187
TRANSACTIONS_PER_ROLLBACK_SEGMENT = 5
After the initial creation of 10 undo segments it proceeds further creation depending upon the values you mention in the init parameter file.

Shout if i'm wrong