It's one of the great riddles that have stumped philosophers through the ages. Which came first, the chicken or the egg? Similarly, the server savants of the modern age ponder yet another riddle: Which is more important in the selection process, the server or the chip?
This article examines how much of a role processor choice plays in server choice. Do people decide on the processor first and then look at other server specs, or vice versa. Or, is the selection made in an entirely different way? How much influence do the AMD, Intel, IBM POWER, and Sun SPARC brand names have when buying a specific box? And what factors do server administrators tend to overlook when evaluating available processor options?
When it comes to choosing the right server, Gartner analyst John Enck says the focus on the processor varies from market to market. When buying a mainframe or other high-end server, he says, very little attention is paid to the processor. Similarly, when buying an x86 server, few can differentiate between Intel Pentium, Intel Xeon, and AMD Opteron however, he feels that AMD is working hard to change this.
"In the midrange market, though, there is more of a focus on processor because these are older processors, and there are more concerns about end-of-life," says Enck. "Remember, this market segment has already said goodbye to MIPS, Alpha, and PA-RISC; as a result, there is more concern about the surviving processor technologies POWER, Sparc, and Itanium."
Dan Olds, principal of Gabriel Consulting Group, goes further. He considers that processors (along with feeds and speeds in general) now play a lesser role in server selection than they did in the past. According to his research, enterprise customers view other server characteristics, such as overall product quality, availability track record/features, and manageability features, as more important than processor type or raw processor speed.
From the OEM perspective, things are a little different. For example, if you choose Dell, by default you are also selecting Intel. Go with a Sun x86 machine, and you are automatically given AMD. IBM and HP, on the other hand, carry both although IBM also stresses its own POWER-processor-based models.
As one example, HP's Christina Tiner, group manager for Industry Standard Systems Enterprise Servers, believes it difficult to categorize all server purchasers. Some customers, she finds, are very loyal to a processor vendor, and some don't care at all.
"Customers vary in the types of servers they purchase and the types of applications they run," she says. "Smart individuals will evaluate processors based on the application and will choose a platform that offers a balanced system architecture that best supports that application."
She states that processors are just one component of the system: A balanced architecture is needed to optimize performance. It encompasses many factors that will exert influence on the purchase decision. This includes storage and I/O subsystems, form factors, and management characteristics.
Enck takes a narrower view, however. In his experience, the decision-making process is largely driven by a core application or an exact server function, such as file/print and Web serving. Once that has been determined, it leads to an operating system, and that narrows the view to a specific hardware platform. At this point, he says, a particular processor comes into the equation. Rarely does he see the decision work the other way.
"In some cases, customers focus on the operating system as the decision point, and that then drives hardware and applications," says Enck. "But in most cases the application is king."
"In the midrange market, though, there is more of a focus on processor because these are older processors, and there are more concerns about end-of-life." John Enck, Gartner analyst
Olds concurs. He sees the same thought stream time and time again. Initially, customers decide on the application they need, and then they look at what platforms support that application. Assuming the application is widely available on several different operating systems, the next phase is to evaluate the system choices.
"This is where it gets interesting and sometimes contentious as vendors vie with each other to show how their particular system is the perfect and only choice to host the application," says Olds.
On a historical note, he comments that things have certainty changed since the tech crash of 2000. In earlier times, most vendors would lead with performance, often relying on raw processor speed as their trump card. In those days, processor performance and system scalability were often regarded as the key differentiators &3151 and there was wide variability between vendors in terms of the size of workloads they could handle. Today, however, we're in an environment where almost every vendor has a system that will provide enough horsepower to handle whatever workload customers care to throw at them.
"Now, with the 'will it get big enough and go fast enough' question out of the way, I see vendors talk more and more about how their systems address other (and often more pressing) customers problems, such as availability, reliability, system utilization, and total costs," says Olds.
And the Brand Plays On
Brand awareness, of course, does play a significant role in what server is purchased. Some enterprises might buy only IBM, and some never. HP and Dell have also earned loyal followings. And some organizations don't care which moniker is on the box so long as the price is right.
It's the same on the processor side. Names like AMD, Intel, IBM Power, and Sun SPARC elicit varying responses. AMD, for example, has been laboring under the shadow of Intel's brand dominance for years. Particularly in enterprise and government circles, the company has fallen foul of buying policy that requires Intel only. More recently, this quasi-monopoly has been broken, driven on by the success of AMD Opteron and the company's lead in the dual-core server chip race.
But Intel has caught up on some of the lost ground, and the differentiating factors may be fading. Enck goes as far as to say that the processor once again has little influence on purchasing. That's why power and cooling, which are normally ignored, are now seeing so much emphasis. This, he says, is why you see AMD claiming power/cooling superiority to Intel and Sun claiming power/cooling superiority over everyone.
"Five years ago no one would have cared," says Enck. "However, this differentiation is not sustainable on the long-term because all processors are heading towards similar power and cooling envelopes."
What factors are most often overlooked? Some buyers pay far too much attention to raw GHz and fail to see beyond that to look at overall performance, cost, and reliability.
"Customers tend to get hung up on the frequency of the processor," says Tiner. "The fact is that there are many processor characteristics that influence performance, including memory architecture and cache size. It's not just about GHz anymore."
Olds reminds buyers to closely consider the processor roadmap when making purchasing decisions.
"Ask questions, like how many revisions of a processor does the vendor have in their current play?" says Olds, "and can these new processors work in existing systems or will they require a forklift upgrade?"
Enck sums it up by saying that organizations overlook factors as much as they are distracted by factors that may or may not be important to them. For example, highly threaded processors may result in better application, or they may not; it depends on the application. Another factor is the current 64-bit rage. Here again, a 64-bit processor may offer significant advantages or not, depending on the application.
"If buyers overlook anything, I'd say they tend to overlook what exact value a processor contributes to their applications and server functions," concludes Enck "They often assume the value is across the board and that isn't always (or even often) true."