With the Cloud Infrastructure Launch on July 12 we announced changes to the vSphere 5 licensing model. vSphere 5 will continue to be licensed per physical processor with a new vRAM entitlement pooled across the entire environment.
We're monitoring the feedback very closely, we take it to heart, and we do want to do the right thing for our customers. In this post, I’d like to point out a couple of things that may have gotten lost in the discussions, share with you some of the thinking behind the vSphere 5 licensing model, and point you to a tool can help you assess what these changes will mean to you.
We are noticing a critical misconception that is permeating many of the discussions around the changes we’ve made. I’d like to clarify: the new licensing model is NOT based on physical RAM. It is based on the amount of virtual RAM (vRAM) configured to a virtual machine. We have seen a lot of instances where people are trying to calculate the number of vSphere 5 licenses needed by taking the physical RAM in a server and dividing it by the vRAM entitlement for a particular vSphere edition. That isn’t quite how the new model works.
The vSphere 5 licensing model has a pooled vRAM entitlement. vRAM is total amount of virtual RAM allocated to all VMs, and it is important to note that the total allocated vRAM for most customers is substantially smaller than the available physical RAM. Most customers reserve at least 20% of spare physical RAM capacity that is not allocated as vRAM.
To really get an understanding of how many vSphere 5 licenses a customer needs, you need to sum up the total amount of vRAM allocated in all powered-on VMs, and divide that total amount by the entitlement for the particular vSphere 5 edition you are running. Let’s look at an example: if you have 100 VMs with 4GB of vRAM each, then you need a vRAM pool of 400GB. If you are running vSphere 5 Enterprise (with 32GB of vRAM entitlement per processor license) then you need 400GB / 32BG = 13 licenses. As you notice, there is no mention of physical RAM in this calculation. To recap, vSphere 5 licensing needs are determined by only 3 factors:
- Number of VMs
- Amount of vRAM per VM
- What vSphere 5 edition you are running. The entitlements for the different editions are available here.
Our Technical Marketing team has developed a tool that can help you add the total amount of vRAM allocated in your VMs so that you can run this calculation. There is also an accompanying video explaining how to use the tool. In addition, we have noticed a few similar tools developed by the community.
How we got to vRAM
When we began the process of developing the new model, we set out to find a way to evolve vSphere’s licensing to lay the foundation for customers to adopt a more "cloud-like" IT cost model. We were looking to develop a model that would be more congruent with the technology architecture of the virtual and cloud world, where resources are pooled for maximum utilization. In short, we wanted a model based on consumption and value rather than physical components and capacity.
The design point of the licensing change was not to increase licensing costs, and we believe 90+% of our customers will not see a licensing cost increase. Before we introduced the new vSphere 5 licensing model, which is based on pooled vRAM entitlement, we did a great deal of research, and carefully analyzed available customer data. Let me tell you what we found:
- The average amount configured vRAM per VM is 3GB
- The average number of VMs per physical processor is 5.7. I know this may be counter-intuitive to some customers who are pushing the envelope, but the detailed distribution of consolidation ratios is on the graph below.
So based on the above two metrics, even if you disregard the effect of vRAM pooling, the vRAM entitlements far exceed the common customer practice. In fact, some customers may see a decrease in their licensing costs: customers of vSphere Essentials, Essentials Plus, Standard, and Enterprise had 6-core per proc restrictions in the previous licensing model. In order to deploy vSphere on a new server with more than 6 cores per processor, these customers would have had to purchase additional vSphere licenses.
We are confident that as we move into the cloud computing era, our vSphere 5 vRAM licensing model will allow our customers to best take advantage of the benefits and flexibility of cloud computing by allowing the pooling of licenses for maximum utilization and value:
- As Forrester’s James Staten writes in his blog: “This change ties licensing more to the use of the product and encourages greater VM consolidation as it counts VMs by size, rather than per physical server. This incents packing lots of VMs on a single system and even lets you share vRAM entitlements across physical systems to accommodate more seamless growth of your environment and management of the pool, a key operational change called out in our Virtualization Maturity Model. Basically, now you can entitle your virtual environment in total, based on its capacity and fill it up as much as you want. This is much more consistent with their service provider pricing model; and if your goal is to build a private cloud, isn’t that the point? All in all, this shows that VMware gets it and is taking an active role in helping educate its customers that virtualization and cloud operations are two different things and making these distinctions clear is critical to their and your success. Well done, VMware.” http://blogs.forbes.com/forrester/2011/07/12/the-cloud-computing-market-grows-up/
- And as the Taneja Group remarked: “We welcome this new approach, and believe it addresses the majority of licensing concerns that we’ve heard from VMware customers over the past couple of years. First, it’s much simpler – users can now focus on how they actually use vSphere virtual resources on a given pool of physical servers, versus having to worry about how those underlying servers’ processor and memory configurations might grow. And since baseline licensing is still tied to number of server cpu’s, the new licensing will not force changes to customers’ existing purchasing and budgeting processes.” http://tanejagroup.com/news/blog/cloud/vmware-takes-vsphere-licensing-to-the-cloud
To wrap up, I would like to point to some of the advantages of the new model as articulated by some of our customers:
I encourage you to download the tool and estimate you actual vRAM usage across your entire environment. Talk to your VMware or partner sales team to go through the numbers. For more information and materials, visit the vSphere 5 Upgrade center.
VP, Product Management