In my rough model of scaled-up data center costs, the highest cost was server hardware, making up 36.9% of the total, including the cost of data storage. You don’t need to think hard before you realize that such costs can vary dramatically. Consider data storage costs. If your data center is feeding video streams to the Internet from a vast video library, like YouTube does, the storage requirement is huge compared to streaming SMS length messages to the world, as Twitter does. Indeed Twitter doesn’t even store its billions of tweets indefinitely, so it can estimate its storage requirements easily on a per user basis, whereas the YouTube library just keeps on growing forever.

The same is true of servers or server boards. You have to have sufficient cpu power and memory for the primary workload. So life is a great deal easier if you have a single workload rather than any kind of mixed load. This in turn means that the economies of scale are going to be better for Software as a Service (SaaS), than for Platform as a Service (PaaS), which in turn will be better than Infrastructure as a Service (IaaS). It’s really all about workloads.

Server Economies of Scale

Let us not forget that we are talking about massive scale here. When you are an old-style data center buying new hardware, you may be able to go to HP and IBM and demand a significant discount on the hardware you intend to buy over the next few years. If you are building a scaled out data center that is designed precisely for a specific workload, you are more likely to go to HP or IBM to discuss the design of the hardware you are going to buy. In fact you might not go to any of the traditional hardware vendors. Instead, you might go to an engineering design company that will design the boards and the networking switches for you and then take the contract to a manufacturer in Taiwan to build the precise hardware that you want.

The point is that if you are going to buy thousands or tens of thousands of servers, you’ve moved to a level of demand where you have choices that the typical data center does not have. You are like a manufacturer designing a new plant who needs to make precise decisions about the tooling of the plant, right down to the design of the robot welders.

I’m not being critical of the server products that are built and delivered by the big computer manufacturers. Such engineering is difficult to be critical of, but all such servers, whether mainframes or cheap commodity server boards are designed for “the average circumstance.” It’s really unlikely that your requirements are anywhere close to the average.

Think first about cooling. Servers and blade cabinets are generally built to go in glass room data centers with raised floors and atmospheric cooling. Cooling is one of your major costs, so you will want the server boards and the data storage to be designed to be exactly complementary to the cooling system and you’ll probably want much more focused cooling.

Now think about cpu, memory and disk. You will want a specific ratio between these that fits the workload. There is no point in having surplus anything, because surplus memory or cpu or disk needs cooling if it’s turned on, and if it isn’t turned on, why have you got it? Now think about whether you want local disk or a huge SAN, or a combination of the two. Think also about failover and redundancy and how the server hardware blends with the networking hardware.

Here’s the point:

If you don’t get the hardware right, then you made a mistake with the biggest cost element in your whole operation.

Only a rank amateur would make a mistake like that.

See also:

The Death of the Data Center: The Model
The Death of the Data Center: Location, Location, Location
The Death of the Data Center: Power
The Death of the Data Center: Cooling
The Death of the Data Center: Networking
The Death of the Data Center: Server Hardware
The Death of the Data Center: The Software
The Death of the Data Center: Software Optimization