PowerManagementASPM

Revision 2 as of 2011-11-12 12:29:34

Clear message

ASPM PCIe Bug

As noted by Phoronix ASPM PCIe power saving has been problematic and a recent patch by Matthew Garrett has re-worked this to clear the ASPM state on all devices on a successful handoff of PCIe control to the OS.

We therefore are providing patched kernels carrying Matthew's fix for testing purposes only to see how well this works across a broad range of machines. Kernels can be found in:

Testing procedure:

  • Ensure laptop is fully charged
  • Unplug AC power
  • Run powertop for 10 minutes on an idle system and note power consumption
  • Plug in AC power
  • Install the new kernel containing the ASPM fix
  • Ensure laptop is fully charged
  • Unplug AC power
  • Run powertop for 10 minutes on an idle system and note power consumption
  • Gather the BIOS version using: sudo dmidecode -t 0 | grep "Version:"
  • Add results to the table below:

Machine

BIOS

32/64 bit kernel

Original Kernel

Original Kernel Power

ASPM fix Kernel

ASPM fix Power

Example

68ET27WW

64

3.1.0-2-generic

23W

3.1.0-2-generic

19W