Cisco Unified Computing System (UCS) (Data Center): A Complete Reference Guide to the Cisco Data Center Virtualization Server Architecture

Chapter 2. Server Architectures

Processor, memory, and I/O are the three most important subsystems in a server from a performance perspective. At any given point in time, one of them tends to become a bottleneck from the performance perspective. We often hear of applications that are CPU-bound, memory-bound, or I/O-bound.

In this chapter, we will examine these three subsystems with particular reference to servers built according to the IA-32 (Intel^® Architecture, 32-bit), often generically called x86 architecture. In particular, we will describe the most recent generation of Intel^® processors compatible with the IA-32 architecture; i.e., the Intel^® microarchitecture (formerly known by the codename Nehalem).¹

¹ The authors are thankful to Intel ...