Optimal settings for rollback segs.

When you set the optimal settings for the rollback segments, I know that Oracle periodically shrinks the number of segments back to the optimal size. When exactly does it do this?

Also, is there a way you can force it to shrink everything back?

Eric Ladner          | UNIX/Oracle/Passport Sys-Administration, General
clad_at_chevron.com     | Applications Development, etc., etc. 


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