Energy-Efficient Computing and Data Centers

Luigi Brochard, Vinod Kamath, Julita Corbalán, Scott Holland, Walter Mittelbach, Michael Ott

• Publisher: Wiley-ISTE
• Year: 2019
• Print ISBN: 9781786301857
• eBook ISBN: 9781119648796
• Edition: 1
• Topic: Computer Science
• Subtopic: Information Technology
• Index: Computer Science

Data centers consume roughly 1% of the total electricity demand, while ICT as a whole consumes around 10%. Demand is growing exponentially and, left unchecked, will grow to an estimated increase of 20% or more by 2030. This book covers the energy consumption and minimization of the different data center components when running real workloads, taking into account the types of instructions executed by the servers. It presents the different air- and liquid-cooled technologies for servers and data centers with some real examples, including waste heat reuse through adsorption chillers, as well as the hardware and software used to measure, model and control energy. It computes and compares the Power Usage Effectiveness and the Total Cost of Ownership of new and existing data centers with different cooling designs, including free cooling and waste heat reuse leading to the Energy Reuse Effectiveness. The book concludes by demonstrating how a well-designed data center reusing waste heat to produce chilled water can reduce energy consumption by roughly 50%, and how renewable energy can be used to create net-zero energy data centers.

1
Systems in Data Centers

There are different types of IT equipment that serve different functions depending on customer application. This chapter provides an overview of servers, storage arrays, switches and their components.

1.1. Servers

A server is a broad term describing a specific piece of IT equipment that provides computing capability and runs software applications in an environment networked with other IT equipment, including other servers. Most servers contain the following major hardware building blocks: processors, memory, chipset, input/output (I/O) devices, storage, peripherals, voltage regulators (VRs), power supplies and cooling systems. Additional application-specific integrated circuits (ASICs) may be necessary, such as an onboard redundant array of independent disks (RAID) controller and a server management controller.

Volume rack-mounted servers are designed to fit within commonly available rack sizes, such as the 19 in. (0.5 m) rack form factor defined by EIA/ECA Standard 310-E specification¹. The vertical dimension is expressed in terms of rack units or just units (U). One U or 1U represents 1.75 in. (44.45 mm) of vertical height within a rack. Servers used for computing are available in standard rack-mount and custom configurations. Typical dimensions and sizes for standard rack-mount compute servers are full-width 1U, 2U or 4U. A single-server chassis may contain multiple server nodes. Each node is defined as containing all key components, except power supplies, needed to make up a complete server. These nodes simply share the larger chassis infrastructure to conserve data center space. For more dense servers, there are 1U and 2U server enclosures that house several 1U ½-width servers.

Microservers are an emerging technology. They are based on system on a chip (SOC) design where all the functions, which are located on a motherboard for a classic server, are integrated on a single chip with the exception of memory, boot flash and power circuits. SOC are usually less power hungry than usual microprocessors leading to microservers that are more dense than classic servers. Although microservers and SOC are not analyzed in the following chapters, they are worth mentioning. These servers generally provide sufficient, targeted performance with optimized performance-per-watt capability, while being easily scalable with shared power and cooling infrastructure for individual servers.

To achieve even higher compute density than the 1U form factor, blade servers are another option. Each ...

Table of contents

• Cover
• Table of Contents
• Introduction
• 1 Systems in Data Centers
• 2 Cooling Servers
• 3 Cooling the Data Center
• 4 Power Consumption of Servers and Workloads
• 5 Power and Performance of Workloads
• 6 Monitoring and Controlling Power and Performance of Servers and Data Centers
• 7 PUE, ERE and TCO of Various Cooling Solutions
• Conclusion
• References
• Index
• End User License Agreement