freebsd stable - Sep 2006 - Changing PMAP_SHPGPERPROC

On FreeBSD 4.11, what is the relationship between PMAP_SHPGPERPROC and
"vm.v_free_min", "vm.v_free_reserved", and
"vm.v_free_target"? For
example, if I increase PMAP_SHPGPERPROC by 1 how do I determine
correct vm values?