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Fedora 20

Power Management Guide

Managing power consumption on Fedora

Edition 1


Red Hat Inc.

Yoana Ruseva

Red Hat Engineering Content Services

Jack Reed

Red Hat Engineering Content Services

Rüdiger Landmann

Red Hat Engineering Content Services

Don Domingo

Red Hat Engineering Content Services

Legal Notice

Copyright © 2013 Red Hat Inc. and others.
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The Power Management Guide documents how to manage power consumption on Fedora 20 systems effectively. It discusses different techniques that lower power consumption for both server and laptop, and explains 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. 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
2.5.1. Plugins
2.5.2. Provided Profiles
2.5.3. Installation and Usage
2.5.4. Custom Profiles
2.5.5. Powertop2tuned
2.6. UPower
2.7. GNOME Power Manager
2.8. acpid
2.9. Other Tools 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. CPU Monitors
3.4. CPU Power Saving Policies
3.5. Suspend and Resume
3.6. Tickless Kernel
3.7. Active-State Power Management
3.8. Aggressive Link Power Management
3.9. Relatime Drive Access Optimization
3.10. Power Capping
3.11. Enhanced Graphics Power Management
3.12. RFKill
3.13. 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