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Red Hat Enterprise Linux 6

Power Management Guide

Managing power consumption on Red Hat Enterprise Linux 6

Edition 1.0


Red Hat Inc.

Don Domingo

Red Hat Engineering Content Services

Rüdiger Landmann

Red Hat Engineering Content Services

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This document explains how to manage power consumption on Red Hat Enterprise Linux 6 systems effectively. The following sections discuss different techniques that lower power consumption (for both server and laptop), and how each technique affects the overall performance of your system.

1. Document Conventions
1.1. Typographic Conventions
1.2. Pull-quote Conventions
1.3. Notes and Warnings
2. Getting Help and Giving Feedback
2.1. Do You Need Help?
2.2. We Need Feedback!
1. Overview
1.1. Importance of Power Management
1.2. Power Management Basics
2. Power management auditing and analysis
2.1. Audit and analysis overview
2.2. PowerTOP
2.3. Diskdevstat and netdevstat
2.4. Battery Life Tool Kit
2.5. Tuned and ktune
2.5.1. The tuned.conf file
2.5.2. Tuned-adm
2.6. DeviceKit-power and devkit-power
2.7. GNOME Power Manager
2.8. Other means for auditing
3. Core Infrastructure and Mechanics
3.1. CPU Idle States
3.2. Using CPUfreq Governors
3.2.1. CPUfreq Governor Types
3.2.2. CPUfreq Setup
3.2.3. Tuning CPUfreq Policy and Speed
3.3. Suspend and Resume
3.4. Tickless Kernel
3.5. Active-State Power Management
3.6. Aggressive Link Power Management
3.7. Relatime Drive Access Optimization
3.8. Power Capping
3.9. Enhanced Graphics Power Management
3.10. RFKill
3.11. Optimizations in User Space
4. Use Cases
4.1. Example — Server
4.2. Example — Laptop
A. Tips for Developers
A.1. Using Threads
A.2. Wake-ups
A.3. Fsync
B. Revision History