1. Computers
  2. Display Drivers
  3. Graphics Cards
  4. Memory
  5. Motherboards
  6. Processors
  7. Software
  8. Storage
  9. Operating Systems


Facebook RSS Twitter Twitter Google Plus


Phoronix Test Suite

OpenBenchmarking.org

Ondemand vs. Performance CPU Governing For AMD FX CPUs On Linux 3.17

Michael Larabel

Published on 2 September 2014
Written by Michael Larabel
Page 1 of 4 - 17 Comments

Given recent comments by Phoronix readers, here are some fresh results from the AMD FX-9590 Eight-Core CPU when testing the different CPU scaling governors with the CPUfreq driver on the Linux 3.17 kernel.

In the tests shared yesterday of looking at the AMD FX-9590 CPU on Linux and other CPU benchmarks from this weekend, some Phoronix readers raised concerns about the CPU scaling governor differences between the AMD and Intel hardware. The AMD FX CPUs continue to use the CPUfreq driver by default to handle their scaling while modern Intel CPUs have the new Intel P-State driver. Beyond the Intel-specific P-State vs. CPUfreq, the AMD CPUs generally default to using the "ondemand" governor while with Intel desktop CPUs on P-State it generally ends up with the "performance" mode. Some Phoronix readers found performance vs. ondemand differences to be unfair, but for AMD FX CPUs, there isn't much of a difference in our common CPU torture test benchmarks found in the Phoronix Test Suite.

To clear up any confusion, with the AMD FX-9590 I ran some of the same CPU benchmarks while measuring the impact between CPUFreq's ondemand and performance scaling governors. All benchmarks were handled by the Phoronix Test Suite, which was also measuring the reported CPU temperature and AC system power usage. This data is shared over the next few pages for this eight-core processor that boasts a 4.7GHz base clock frequency and 5.0GHz turbo frequency.

For those that missed it, earlier this year I did an Intel P-State vs. CPUfreq Comparison as an equivalent Intel article to these AMD Linux benchmarks

Latest Articles & Reviews
  1. Preliminary Tests Of Intel Sandy Bridge & Ivy Bridge vs. Broadwell
  2. AMD FX-8320E Performance On Linux
  3. Linux Compiler Benchmarks Of LLVM Clang 3.5 vs. LLVM Clang 3.6-rc1
  4. Intel Broadwell HD Graphics 5500: Windows 8.1 vs. Linux
  5. Linux Benchmarks Of NVIDIA's Early 2015 GeForce Line-Up
  6. NVIDIA GeForce GTX 960: A Great $200 GPU For Linux Gamers
Latest Linux News
  1. Now-Closed KDE Vulnerabilities Remind Us X11 Screen Locks / Screensavers Are Insecure
  2. Vivaldi: A New Chromium-Powered, Multi-Platform Browser
  3. KDE Plasma 5.2 Officially Released
  4. Intel Broadwell On Linux Has Working OpenCL 1.2, VP8 Video Acceleration
  5. GParted 0.21 Brings ReFS Detection, EXT4 For RHEL5, Reiser4 For Linux 3.x
  6. Wine Staging Update Has Better CUDA Support, Driver Testing Framework
  7. Nouveau In Linux 3.20 Will Have A Lot Of Code Cleaning
  8. Compare Your Linux System To The i7-5600U Broadwell X1 Carbon ThinkPad
  9. Debian 8.0 "Jessie" Installer RC1 Released
  10. Chromebook "Rush" With 64-bit Tegra SoC Support Lands In Coreboot
Most Viewed News This Week
  1. Windows 10 To Be A Free Upgrade: What Linux Users Need To Know
  2. LibreOffice 4.4 Is Coming Soon With New Features
  3. Google Admin Encourages Trying Btrfs, Not ZFS On Linux
  4. TraceFS: The Newest Linux File-System
  5. My Initial Intel Broadwell Linux Experience With The ThinkPad X1 Carbon
  6. Keith Packard Leaves Intel's Linux Graphics Work
  7. Interstellar Marines On Linux With Catalyst: Bull S*#@
  8. Faster VP9 Decoding Is On The Horizon