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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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Database server CPU capacity is calculated in the same manner as the Oracle CPU utilization. Placing both the requirements and capacity into the utilization formula and applying the appropriate conversion factors, we have this calculation:
This means the CPU subsystem is operating on average at 100% utilization! We should have expected this, since Oracle is consuming 94% of all the available CPU. Calculating both Oracle CPU utilization and the operating system CPU utilization, we have a very nice confirmation that this is the only instance running on the database server and also that the CPU subsystem is experiencing a raging bottleneck.
The utilization formula implies a linear relationship between requirements and utilization. In other words, if the requirements double, so will the utilization. When you are asked, "But how do you know it really works like this?" show the graph in Figure 9-7, or better yet, create one yourself. While no real Oracle system will match this perfectly, for CPU-intensive systems, the linearity is very evident.
©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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