kstats are data structures maintained by various kernel subsystems and drivers. They provide a mechanism for exporting data from the kernel to user programs without requiring that the program read kernel memory or have root privilege. For more information, see kstat(3KSTAT).
Starting in the Solaris 8 release, the kstat(1M) command is available to enable selection and display of kstats with a command-line interface. A Perl module, kstat.3ext, is also available to process kstat information.
kstats with system_pages name in the unix module do not report statistics for cachefree because cachefree is not supported in the Solaris 9 release.