Rollback segment space allocation

The other day I dropped and recreated my rollback segments. I created my tablespace with 70M of space, and then I created 10 rollback segments using the command:

create rollback segment r? tablespace rbs_tsp storage (initial 3M next 3M maxextents 2 pctincrease 0)

I then stopped and started the database, using the new rollback segments. I immediately ran a space usage report on the tablespace, which reported that 60M were allocated. I was under the impression that when an object was created, only the initial extent was pre-allocated. Since this report was run before anyone could use the rollback segments. How come 60M were allocated, rather than 30M?

BTW, this is a v6 database.

Mike Dickson                            | mdickson_at_halycon.com
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