Kernel Values, Tunables, and Defaults

In this section I describe the most important kernel variables that can be used to tune the virtual memory system. They are normally set in the /etc/system file. Figure 13-9 illustrates the relationship between the parameters that control page scanning.

Figure 13-9. Parameters to Control Page Scanning Rate and Onset of Swapping


The fastest scan rate, corresponding to an empty free list. It can be reduced if lotsfree has been increased, but it must be more than slowscan. fastscan can be changed on line. fastscan is set to (physmem/2) in Solaris 2.1 through 2.3 and (physmem/4) with a limit of 64 ...

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