These past few days, we've seen some back and forth postings taking place on various corporate blogs around the topics of virtualization ROI and a unique feature found in VMware ESX Server called memory overcommitment.

VMware's Eric Horschman posted an interesting blog post on VMware's Virtual Reality Blog site answering remarks made by many in the industry that VMware's solution is overpriced. Many have said that with companies giving away platforms built on top of Xen, and Microsoft planning on charging $28 for their yet to be released Hyper-V hypervisor, it seems as though VMware's price tag could be a little steep and might have to come down to a price that is more "reasonable".

Horschman countered the 'high pricing' claim saying "Virtualization customers should focus on cost per VM more than upfront license costs when choosing a hypervisor. VMware Infrastructure's exclusive ability to overcommit memory gives it an advantage in cost per VM the others can't match." And he adds, "Our rivals are simply trying to compensate for limitations in their products with realistic pricing."

To back his claims up, Horschman lays out an elaborate presentation and example of how to calculate this cost per VM, and attempts to show readers how a free hypervisor ends up costing more money per VM than that of the more expensive ESX Server product because of the memory overcommitment feature currently exclusive to VMware.

Roger Klorese, Senior Director on the Product Marketing team for Citrix XenServer, answers Horschman's post with a blog posting of his own. As a side note, in addition to now working at Citrix on the XenServer product, Klorese was, in another life, an early member of the VMware family and so he draws on some of his past experience with the ESX Server product.

...

Read the rest of my article at InfoWorld, here.