Understanding the ins and outs of industry benchmarks is the key to assessing processor suitability for a given implementation.

By Andrew Binstock

Prospective purchasers of the Intel® Xeon® processor cannot help but notice that the higher-end, more expensive processors run at slower clock speeds than their low-end counterparts. This difference is counter-intuitive, and even more so when we consider Intel’s long-standing use of clock speed as a proxy for processor performance.

So the question arises: "what is happening?" Are the high-end processors faster or not? And do they represent a better solution than their quicker-clocked brethren? There is no doubt that the Intel Xeon Processor MP provides the greater throughput for server applications, despite the lower clock speed. This article examines how it accomplishes this performance and why it seems to conflict with the specifications of other models of the Intel Xeon processor.

To get a handle on this set of questions, it is important to consider the history behind the two main branches of the Intel Xeon processor family. Prior to the advent of the Pentium® 4 processor, the Intel Xeon processor was qualified by the name of the Pentium logic that resided in their cores.

Hence, you can still find Pentium II Xeon processors and Pentium III Xeon processors as well. These chips were broken out into two branches: front-end Intel Xeon processors and their server-oriented counterparts, the back-end Intel Xeon processors. The latter chips were distinguished by uniformly larger caches.

When Intel began shipping the Pentium 4 processor in 2000, it changed the positioning and the names of its various processor families. Processors bearing the Pentium name were consigned to single-processor desktop systems. Intel Xeon processors, no longer prefixed with the Pentium qualifier, were intended for the small-to-midsized server market. These two processor families were sandwiched between the value-oriented Celeron® processors below them and the Itanium® processors above them.

When this new processor roadmap was laid out, Intel Xeon processors were further divided into two categories: Intel Xeon processors (with no "MP" suffixed to the name) were oriented towards high-end workstations and small workgroup servers. The mid-sized server market was served by the Intel Xeon processor MP. The “MP” indicates a design suitable for multiprocessing configurations, meaning that they target systems that scale beyond two processors.