The ESTAT events report indicates that you are getting busy buffer waits. What method can you use to find out what is causing this?

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When the ESTAT events report shows that you are getting buffer busy waits, it normally indicates that there is contention in redo, rollback, or data blocks. When this occurs, I check the vwaitstat view to see what may be causing the problem. I look at the value of the 'count' column to see where the problem is and the 'class' column to see what may be causing it. UNDO indicates the issue is related to the rollback segments, and DATA tells me it is in the database buffers.