Named kstats are an array of name-value pairs.
These pairs are kept in the kstat_named structure. When a kstat is created by kstat_create(9F), the driver specifies
how many of these structures will be allocated. The structures are returned as an array pointed to by the ks_data field.
union {
char c[16];
long l;
ulong_t ul;
longlong_t ll;
u_longlong_t ull;
} value; /* value of counter */
The only member exposed to drivers is the value member. This field is a union of several data types. The driver must specify which type it will use in the call to kstat_named_init().