Fragmentation Help

| Rollback Segment Contention Help |
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Rollback segment activity is an important facility to monitor in your database to maintain reliable performance. Whenever a transaction modifies a block of data in your database, rollback segments provide a read-consistent view to the other sessions in the database, giving the a picture of the data before any changes were begun. Additionally, as with redologs, rollback segments are important for database recovery. As with other facilities, we can monitor the hitratio for rollback segments to see if we have any problems. Here's an example of how to configure karma to monitor your rollback segments: rollback:10:Y:Z In this example we're monitoring every 10 minutes. Y and Z flag a WARNING and ALERT respectively, although it hasn't been finalized exactly how this functionality works yet.