The content of the file is a line of the following form:
/dev/vt dev/kd/kd num
By default num is set to the maximum of 15. This specifies that VTs /dev/vt00 through dev/vt14 are available for use. Valid values for num are in the range 1-15.
System resources are not actually consumed until a VT is opened, and the resources are released when it is closed. To save system resources you can reduce the number of VTs available. Do this by editing this file and changing num to the number of VTs desired. The system must be rebooted before the new value of num takes effect.