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

Ubuntu 11.10 Beta Has No Power Regression Fix

Ubuntu

Published on 01 September 2011 10:02 AM EDT
Written by Michael Larabel in Ubuntu
11 Comments

Canonical's Kate Stewart set a milestone for correcting the ASPM power issue by Ubuntu 11.10 Beta 1. Ubuntu 11.10 Beta will be released today, but it will not fix the Linux 2.6.38 power regression that's caused by a change in PCI-E Active State Power Management.

A month ago I wrote, "A few hours ago, Kate Stewart marked LP bug #760131 as being a milestone candidate for Ubuntu 11.10 Beta 1. This bug is for the main power regression introduced in the Linux 2.6.38 kernel as caused by PCI Express Active-State Power Management changes. There hasn't been a "solution" upstream in either the Linux 3.0 or 3.1 kernels yet since this is a tough problem. I'm not sure what Canonical is planning to do to "fix" the situation (considering their overall lack of low-level technical contributions particularly in the kernel area) besides possibly forcing PCI-E ASPM or just postponing the fix to a later milestone."

Sure enough, a fix has been delayed. Martin Pitt has changed the milestone target for triaging from Ubuntu 11.10 Beta 1 to Ubuntu 11.10 Beta 2. That's still extremely optimistic. The second beta is due out on the 22nd of September, but still it's unlikely to see a PCI Express ASPM change within Ubuntu 11.10. The 15th of September also marks the kernel freeze for Ubuntu 11.10, so unless they come up with some sort of workaround (such as forcing PCI-E ASPM on my default, but that could crash some systems), there won't be any fixes for the Oneiric Ocelot release.

Heck, we'll only likely see a real fix in Ubuntu 12.04 LTS if the upstream kernel developers address the problem by coming up with a new way to more accurately determine when PCI Express Active-State Power Management is supported or not. This likely will come down to testing hardware/driver combinations and having each driver set the ASPM supported bit flag when it's known to work safely, since many system BIOSes aren't advertising their ASPM support when in fact the system can handle this power management feature.

There's no real improvement with the Linux 3.1 kernel and I haven't seen anything queuing up yet for the Linux 3.2 kernel. In fact, with Intel graphics the power consumption can go up in Linux 3.1. There's also other Linux power management regressions still outstanding.

The tracking of the ASPM power management regression can be done via LaunchPad Bug #760131, "Power consumption raised significantly in natty."

About The Author
Michael Larabel is the principal author of Phoronix.com and founded the web-site in 2004 with a focus on enriching the Linux hardware experience and being the largest web-site devoted to Linux hardware reviews, particularly for products relevant to Linux gamers and enthusiasts but also commonly reviewing servers/workstations and embedded Linux devices. Michael has written more than 10,000 articles covering the state of Linux hardware support, Linux performance, graphics hardware drivers, and other topics. Michael is also the lead developer of the Phoronix Test Suite, Phoromatic, and OpenBenchmarking.org automated testing software. He can be followed via and or contacted via .
Latest Linux News
  1. Yet Another OpenGL 4.5 Extension Is Nearing Completion In Mesa
  2. Xfce's Power Manager Is Finally Ported To GTK3
  3. The CompuLab Fitlet Is A Neat Little Linux PC With AMD SoC
  4. AMD & Others Are Working On The LLVM SPIR-V Converter
  5. Linux 4.1-rc5 Kernel Released
  6. Mesa 10.5.6 Brings Fixes All Over The Place
  7. NVIDIA's Proprietary Driver Is Moving Closer With Kernel Mode-Setting
  8. The Latest Linux Kernel Git Code Fixes The EXT4 RAID0 Corruption Problem
  9. Features Added To Mesa 10.6 For Open-Source GPU Drivers
  10. Ubuntu's LXD vs. KVM For The Linux Cloud
Latest Articles & Reviews
  1. Opening The Gates To Our Daily Open-Source Linux Benchmark Results
  2. The Latest Features For Linux Performance Management + Benchmark Monitoring
  3. Noctua NH-U12DX i4 + NF-F12
  4. Btrfs RAID 0/1 Benchmarks On The Linux 4.1 Kernel
Most Viewed News This Week
  1. The Linux 4.0 Kernel Currently Has An EXT4 Corruption Issue
  2. The Linux 4.0 EXT4 RAID Corruption Bug Has Been Uncovered
  3. Microsoft Open-Sources The Windows Communication Foundation
  4. Systemd 220 Has Finally Been Released
  5. NVIDIA's Proprietary Driver Is Moving Closer With Kernel Mode-Setting
  6. Another HTTPS Vulnerability Rattles The Internet
  7. LibreOffice 5.0 Open-Source Office Suite Has Been Branched
  8. LibreOffice 5.0 Beta 1 Released