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Oracle Performance Firefighting, written by
Craig Shallahamer of
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©2009, 2010 by Craig Shallahamer. This is copyrighted material.
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The Oracle and application tuning strategies are intended to reduce the number of IO read calls, making an increase in IO activity and subsequent IO performance issues highly unlikely.
To summarize, by reducing both physical and logical block activity, performance can be significantly improved. This means SQL tuning and/or reducing SQL statement execution rates. Figure 9-23 shows there are three high-consuming physical IO SQL statements, with the top statement consuming more than twice as much physical IO as the second and third ones combined! Figure 9-24 shows the system is processing nearly 70 logical IOs each millisecond.
Figure 9-23. Shown is the essential application SQL information entered (obviously copy and pasted) into a template. All the information was gathered during the 30-minute collection interval from v$sql and represents only what was processed during the collection interval. Notice the most resource-consuming statement is not the slowest and consumes no more resources per execution than other statements. It's the combination of execution rate and per-execution resource consumption that makes it stand out.
©2009, 2010 by Craig Shallahamer. This is copyrighted material.
PleaseOut of respect for those involved in the creation of the book and also for
their familes, we ask you to respect the copyright both in intent and deed. Thank you.
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