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Oracle Performance Firefighting, written by
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©2009, 2010 by Craig Shallahamer. This is copyrighted material.
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When available, the scan rate can be seen in vmstat reports, in the sr column. When running sar, the command-line option is -g.
I have learned over the years that memory issues are one of the most sensitive issues for administrators and especially with vendors. When you see a memory bottleneck, think there may be one, or you're just not sure, simply ask the operating system administrator. If you run the commands I presented, give the situation some thought, and then approach the operating system administrator, he should respect your honest and concerned request.
Every modern operating system does not swap entire processes. However, the word swap is still used in common commands such as vmstat and sar. To ensure you are not tackled by an operating system administrator, always use the term pages swapped (which is essentially just like a page getting paged out), instead of a process being swapped out, process swapping, or even just swapping. I typically say, "pages being swapped out" so I can move on. If you still get hassled, ask the aggressor to check the manual page on either vmstat or sar, and he will see it says something like the Red Hat Linux vmstat manual page: "Total number of swap pages the system brought out." Maybe it's not too informative, but that's what it says.
©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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