RHEV-H 3.y - swap allocation

Hi

I have a question around the automatic allocation of swap partition during the RHEV-H installation.

According to the documentation, the amount of swap configured at build is determined by the following calc :-   (physical mem x 0.5) +  2,4,8 or 16G - depending on amount of phys mem

For my new system with 256G of physical memory the result would be :-

(256 x 0.5) + 16 = 144G swap partition

Baring in mind that KSM is taking very good care of memory overcommit at the VM level, why does the installer insist on configuring such a huge swap partition ? 

I understand it very bad news to have memory pages allocated to a VM in swap, especially when it comes to live migration, but its I would think it unlikely that a RHEV Hypervisor configured to allow 150% memory optimisation would start paging. 

Thanks