Question about /boot/home/config/settings/kernel/drivers/virtual_memory

Hello. I was looking around the settings files, and found this:
In the /boot/home/config/settings/kernel/drivers/virtual_memory settings file, I have the following variable:

swap_volume_capacity 6292305920

I found that the value in this key is equal to the total file size of my partition (volume). Maybe this is a dumb question, but:

Why there are the “total size” of the partition, instead of “free space size” of the partition?

Thank you!

/boot/home/config/settings/kernel/drivers/virtual_memory

file:
vm on
swap_auto yes
swap_size 5705302016
swap_volume_name 11
swap_volume_device /dev/disk/scsi/0/0/0/1
swap_volume_filesystem bfs
swap_volume_capacity 215869292544

From what I understand, swap_volume_capacity 6292305920 is the capacity of the volume ( disk partition ) that the swap file is located on. The swap_size is the size to the swap file. The swap_size cannot match the swap_volume_capacity unless the swap_volume_name is different than the boot volume.

One can only use the whole partition for the swap file if he has set a partition other than boot to hold the swap file.