Oracle connector metrics tracking of rollback and abandoned transactions may cause high memory usage

The Oracle streaming metrics track each abandoned and rollback transaction id in an array that grows unbounded. In a situations where a connector runs for a long period of time where lots of transactions are rolled back or abandoned, this can lead to high memory usage.

We should either:

1. Not track these ids
2. Track only the most recent X number of ids

I'm personally in favor of 1 as there is little value that comes from (2).