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Oracle Performance Firefighting, written by
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6 I used OraPub's Statistical Significance Template spreadsheet. To locate and then download the spreadsheet for free, go to OraPub's web site and search for "stat sig."
7 When a process is serviced by one CPU and then is switched to another CPU, it undergoes a context switch. The vmstat report's cs column shows the number of systemwide context switches per second during the reported interval. An operating system administrator can help you determine if the log writer (or any process for that matter) is experiencing too much context switching at the expense of not getting enough service time. Exclusively binding a CPU and process together virtually eliminates context switching, because the CPU will always be there for that process and the process will never need to wait while the operating system switches its processing to another CPU.
8 There are many factors involved in deciding how fast redo log switches should occur. Paramount is recoverability and mean time to recover, not performance. Once the availability issues have been addressed, then work on slowing redo log switch time until the associated wait events are insignificant.
©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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