[Q] Rollback segment deallocation

From: Mike Campbell <mlcampb1_at_ingr.com>
Date: 1995/05/24
Message-ID: <3q01q4$c8n_at_b10.b10.ingr.com>#1/1

I've been trying to do some testing to make my rollback segments shrink back to the optimal size I've defined, but can't seem to make them decrease in size. If I create a rollback segment with an initial size of 20K and set and optimal size at 26K I can use sqldba monitor rollback segments to verify that it got created successfully.

Now I use the set transaction command to force Oracle to use my newly created rollback segment and insert 7500 rows into a table. In another window I can see the size of my rollback segment grow continually as well as additional extents being allocated.

Once I commit the inserts though I thought that my rollback segment would reduce back to my optimal 26K size but it doesn't. I even tried issuing another command to force it to extend my rollback segment further, but once again when it is finished and I commit, the space is still allocated to the rollback segment.

What gives here? Am I doing something wrong or what? How do I force the rollback segments to shrink?

Thanks,

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Mike Campbell
Senior Support Engineer
Intergraph Corp.
Huntsville, AL 35894-0001
mlcampb1_at_ingr.com Received on Wed May 24 1995 - 00:00:00 CEST