When running a stress test environment, waiting for the event title in the top N. Do not check, know that it is because undo competitive event.
According to metalink document explains, it is due to lack of space caused undo table.
This implies that sessions are struggling to find new undo extents and are having to steal.
"ktusm_stealext_2" is used to steal undo extents. As _undo_autotune is FALSE then the undo retention should be static.
In conclusion, this problem could occur if available undo space is not enough.
"ktusm_stealext_2" is used to steal undo extents. As _undo_autotune is FALSE then the undo retention should be static.
In conclusion, this problem could occur if available undo space is not enough.
Description This waiting and hidden parameters _undo_autotune set to UNDO insufficient space under the circumstances of FALSE
The current database is truly closed _undo_autotune function. And LATCH undo global data up waiting to happen in ktusm_stealext: KSLBEGIN place, indicating that the session when looking for a new UNDO EXTENTS, had to Steal unexpired UNDO EXTENTS.
Solution three: the length of time to reduce UNDO_RETENTION parameter set; to increase the size of UNDO_TABLESPACE; _undo_autotune hidden parameters will be set to TRUE.