Rollback segments, ORA-01581

Hi Group,

I experienced problems with the rollback segements now and then in the past but shrugged it off since nothing of significance happened to the calling application. But for some days the error ORA-01581 starts popping up for about every update/delete command I issue. I know the purpose of rollback segments, I know they have to be big to handle long transactions such as batch runs etc. Our rollback segments are ***HUGE*** (about one third of the database size), they are set to autoextend, unlimited extents and the database is configured to
"unlimited_rollback_segments = true". And there is PLENTY of diskspace.
It's Oracle workgroup server 7.3.3.4 on NT 4.0 SP 3, PII-200, Raid 5 Disk Array.
Today ORA-01581 came up when a user tried an update of 75 rows - ridiculous. So I started a very big update and watched the storage managers statistics. The point is: Nothing happened to the size of the rollback segments or their datafiles sizes (Pl dont ask, Yes, I did refresh the display expicitly about every 10 secs!). Just when the error occurs the value "high water mark" will be greater than the value
"size", the affected rollback segment will change its status from
"online" to "full" and that's it. The calling application will throw an
exception (or the SQL Worksheet show the error), then the transaction will be rolled back. If I repeat this update a few times other rollback segments will be affected.

Thank You for hearing me out, now the question: Considering the described configuration, WHY won't Oracle claim diskspace as needed for the rollback segments and their datafiles??? Any help appreciated!

TIA Ralph Received on Wed Nov 17 1999 - 18:43:53 CST