So I got another hand me down machine, this time an XW4600 (NewServerDay!), and I want to put a hypervisor on there. So I figure since I have a ton of time dealing with ESX/vSphere, I'd try something different and do Xenserver's free product.
The only problem is, I've only got a quad core and 8GB of RAM, and the free version of Xenserver doesn't support memory over-commit. Fail.
So, back to ESXi I go. It's not that all the VM's will simultaneously need to go full tilt at max RAM at the same time. But it's nice to allow servers to go that high in bursts, if need be.
I guess they have to upsell somehow, but seeing as how this is just in my Secret Underground Lair, I don't need to pay for it.
You don't want to use Xen for anything, dude. It seriously sucks.