I'm looking to understand what are the pros and cons of OVM vs ESXi?
Oracle OVM is replaced by oracle OLVM. KVM replace XEN. oracle is cheaper than VMware and Oracle allows hard partioning on their products. So the license costs for the Oracle database or WebLogic server can be reduced.
Technically both products are good enough.
But as tested, Oracle VM is best for Oracle Databases & Apps.
While VMWare is best for Windows and linux VMs .
Oracle databases, as well as apps performance, are much better and stable on the Oracle VM server. E.g., 1TB of the VM is cloned in just five minutes. The backend file system is different.
VMware is more popular. OVM or better OLVM is good for Oracle products because provides "hard paritioning".
I am just a newbie in Red Hat/Linux VM - KVM. I don’t think I can be of help here. You could ask one of the EU Red Hat representatives from the business card included for better help.
I recommend VMware, which is stable when putting it to production, you just need a server with enough memory and you will realize that VMware is the one.
Can you explain what an IOMMU is? How does it improve VM performance?