How does CPU-based pricing work?

Question

1. What is CPU-based pricing and how does it work?
2. How does it differ from other pricing models like user-based, server-based etc.?

This is just my understanding of this term, please correct me if I'm wrong. This makes sense only when there are load balancing and clustering of servers in place.

Any pointers to links, documentation are also appreciated.

For example, I can quote a line which I recently read: $9000 for 2 CPU Server

Answer 1

Per-CPU based pricing is an incredibly vague term, and you really need to contact the vendor of yor software to find out what they mean by it.

It's so vague in fact that Microsoft have not done per CPU licensing for a long time, because what comprises a CPU these days is very debatable.

• Is each CPU a physical chip sitting in a physical socket?
• Is each CPU a logical core of each physical CPU sitting in a socket?
• Is each CPU a thread of a logical core of a physical CPU sitting in a socket?
• If you have a partitioned server, do you need to license each socket inside the partition, or do you need to license each socket in the entire server?
• If you're running a virtual machine, do you need to license each VCPU or each logical core or each physical socket?

Microsoft thus use per socket licensing model, Oracle user a per core licensing model, and as far as I know nobody uses the per thread licensing model. Licensing models for Virtual Machines vary wildly for each vendor.

So there's no way anyone can answer your question with any real certaintly unless you contact the vendor of the software.

Answer 2

The line you read just means a machine with 2 cores, but this is not how CPU-based pricing really works.

CPU-based pricing is sold in CPU-hours, which is basically a single core running at 100% for a solid hour. Fractional loads and fractional periods have fractional costs. So if a CPU-hour costs you $1.20, then running at 25% load for half an hour will cost you $0.15.

Answer 3

For software licenses, "CPU-based pricing" usually means that you're charged on the number of CPUs that can run a given application. This tends to be the same as the number of cores installed in the server where the software runs, as I've never seen CPU-based charges for anything but server-based software (rather than desktop-based).

Answer 4

"$9000 for 2 CPU server" means you are licensed to run the software on a server with two CPUs. This could be two physical CPUs or two cores -- you'll need to check with the vendor to clarify.

Things get a little more interesting (frustrating?) when VMs are involved, too. Here is an example of Oracle pricing when virtualization is factored in.

Answer 5

Some vendors, such as Oracle, associate a weighting to the core-count, according to the architecture. For example, their weighting for Intel multi-core CPUs used to be 0.5, so if you had a dual-core, dual-socket server, the actual licensed CPU count would be 2 x 2 x 0.5 = 2. You'd then pay circa £45K (list) for each CPU license. Not that I'm bitter about Larry's costs ;-)