MV logs with Oracle's auto extent control

We're using materialized view logs for data capture. There are no materialized views being refreshed from these logs. Instead our ETL team reads the logs (we capture all columns) and duplicates the insert, update, or delete. After they're done they truncate the logs.

We're also letting Oracle automatically handle the next extent size.

The problem is that the extent size of the single extent remaining after the truncate is around 8M while the single extent for a newly created table is 62K.

My question is, is Oracle not resetting the number of times extended counter when the ML log is truncated? You'd think that a smart algorythm would notice when the table had been truncated. On the other hand, we're using this mechanism in a way that Oracle never intended it to be used.

I know how the auto extension sizing is supposed to work. I'm just wondering if there's someone on the list who knows enough about the internals of the algorythm to shed some light on why the MV Log isn't dropping back to the smallest extent size?

Thanks

(algorythm --- does that mean that a former US Vice President is a great jazz drummer?)

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