Nothing will happen , The size of the swap relative to the size of the memory is a recommendation(There is more than one opinion) and is noncommittal .
(google translate)
As far as I know, swap size should be at least the RAM if you use functions like suspend on RAM, kdump, or something like these.
In other cases there is people that doesn’t configure swap at all, stating that if a system is swapping, something is going bad, and more swap the system uses, more things are going bad. Even if swap is not always and solely used if there is a shortage o free RAM.
In my case I had to reduce my home lv before I could increase swap.
Because you have to resize your filesystem as well I booted via gparted-live and followed the instructions on this page
Afterwards I followed the instructions in your provided link to increase swap for lvm.
Maybe it’s worth putting this into a how-to section or so…
Anyway, thanks for the link.