i have needed to use filesystem swap, i now want to increase its size, how do i tell the system to unmount it so i can increase its size, as its in use all the time?
You would need to boot into single-user mode, which is before any swap is activated.
Now, hopefully you are not wanting to extend your Primary Swap partition (vg00/lvol2) because the only real supported way to do that is via an Ignite make_tape_recovery tape.
If it is a different swap area, then you can extend it via lvextend.