Philippe Makowski wrote:

> Database header page information:
> Oldest transaction 18091
> Oldest active 18092
> Oldest snapshot 3280
> Next transaction 35875

My guess is that transaction 18092 overlapped transaction 3280 so
data from that transaction can't be garbage collected or it would
invalidate the database snapshot that 18092 needs to maintain a
consistent view of data. Since there are nearly 18000 transactions
between the oldest active and the next, it's not unlikely that
transaction 3280 lasted long enough to cross paths with a transaction
15000 starts later.

Regards,


Ann