If there are operations already being performed on those tables at the time you start the rebuild / reorganize, then you will see a delay. Rebuilding and reorganizing also will cause some blocking and you will take a performance hit while the operation is running.
You should run these types of activities during off hours and in a maintenance window.
Jason...AKA CirqueDeSQLeil
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I have given a name to my pain...MCM SQL Server, MVP
SQL RNNR
Posting Performance Based Questions - Gail Shaw[/url]
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