Randomly getting ORA-08177 with only one active session

Question

I\'m running a program that creates a table and then inserts some data.
This is the only program that accesses the database.
I\'m getting ORA-08177 randomly.
Act

Answer 1

Total rewrite (having barked up the wrong tree the first time around).

The SERIALIZABLE isolation level grabs a slot in the Interested Transactions List. If Oracle cannot get a slot then it hurls ORA-8177. The number of available ITL slots is controlled by INITRANS and MAXTRANS. According to the documentation:

To use serializable mode, INITRANS must be set to at least 3.

This must be set for both the table and its indexes. So, what are your INITRANS settings? Certainly your sample code uses the default value (1 for tables, 2 for indexes).

Answer 2

In comments user Gary posted a link to thread that explains this strange behavior. Shortly, sometimes during index restructurization undo data becomes unavailable. Any transaction that runs at serializable isolation level and requests the data that is somehow related with this index will get ORA-08177. This is a half-bug half-feature of Oracle. ROWDEPENDENCIES reduces the chance of getting this error. For my application I've simply switched to ReadCommited level for large data uploads. It seems that there is no other way to escape this problem completely.

Thanks, Gary, I've upvoted your answer to other question.