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 Benchmarking Platform
Phoromatic Test Orchestration

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. Ubuntu 15.04 Offers Faster OpenGL For AMD Radeon GPUs On Open-Source
  2. Ubuntu 15.04 Brings Some Graphics Performance Improvements For Intel Haswell
  3. Sub-$20 802.11n USB WiFi Adapter That's Linux Friendly
  4. The Lenovo T450s Is Working Beautifully With Linux
  5. Linux 4.0 SSD EXT4 / Btrfs / XFS / F2FS Benchmarks
  6. Linux 4.0 Hard Drive Comparison With Six File-Systems
Latest Linux News
  1. The Difference In Optimizations Between NIR & GLSL
  2. OpenMandriva Lx 3 Alpha: Adds UEFI Support, Defaults To LXQt
  3. Systemd Kills Off Shutdownd
  4. There's Now More Than 1,100 Games On Steam For Linux
  5. Btrfs In Linux 4.1 Has Fixes For File-Systems Of 20 Terabytes & Up
  6. Microsoft's CoreCLR Now Works On FreeBSD
  7. Unigine 2.0 Beta 2 Brings PBR, SSR, Kinect 2 Support
  8. KDBUS Still Hasn't Been Pulled, Might Not Land For Linux 4.1
  9. The State Of The Lima/Tamil Driver Code
  10. The New Linux Performance Test Lab Is Already Being Expanded
Most Viewed News This Week
  1. AMD Releases New "AMDGPU" Linux Kernel Driver & Mesa Support
  2. EXT4 In Linux 4.1 Adds File-System Level Encryption
  3. AMD Open-Sources "Addrlib" From Catalyst
  4. My Favorite Computer Desk Of The Past Decade For Less Than $100
  5. Library Operating System (LibOS) For Linux Still Being Pursued
  6. Linux-Powered Endless Computer Raises $100k+ In A Few Days
  7. Features Thus Far For The Linux 4.1 Kernel
  8. GIMP's Porting To GTK3 Continues