Section 6.12. Obtaining Memory Kstats

6.12. Obtaining Memory Kstats

Table 6.3 shows the system memory statistics that are available through kstats. These are a superset of the raw statistics used behind the vmstat command. Each statistic can be accessed with the kstat command or accessed programmatically through C or Perl.

Table 6.3. Memory-Related Kstats

Module	Class	Name	Description
unix	pages	system_pages	Systemwide page count summaries
unix	vm	segmap	File system mapping statistics
unix	kmem_cache	segvn_cache	Anonymous and memory mapped file statistics
unix	hat	sfmmu_global_stat	SPARC sun4u MMU statistics
cpu	misc	vm	Systemwide paging statistics

The kstat command shows the metrics available for each named group; invoke the command with the -n option and the kstat name, as in Table 6.3. Metrics that reference quantities in page sizes must also take into account the system's base page size. Below is an example.

$ kstat -n system_pages module: unix                      instance: 0 name:   system_pages              class:    pages         availrmem                 343567         crtime                    0         desfree                   4001         desscan                   25         econtig                   4278190080         fastscan                  256068         freemem                   248309         kernelbase                3556769792         lotsfree                  8002         minfree                   2000         nalloc                    11957763         nalloc_calls              9981         nfree                     11856636         nfree_calls               6689         nscan                     0         pagesfree                 248309         pageslocked               168569         pagestotal                512136         physmem                   522272         pp_kernel                 64102         slowscan                  100         snaptime                  6573953.83957897 $ pagesize 4096