How to fix excessive power consumption of kernel 2.6.38

According to Phoronix and its creator, Michael Larabel, the great cause of the problem of energy consumption in kernel 2.6.38 is the change that was made in the call ASPM (Active-State Power Management) for PCI Express slots.

The Active-State Power Management feature allows you to reduce power consumption by putting PCI Express links that are not in use in a power-saving state, making them less active over time. This is a common feature in laptops and other mobile devices used to extend the life of batteries.

Apparently, the cause of the problem with the latest Linux kernels is the misconfigured BIOSes, since many laptop manufacturers support ASPM but do not configure it correctly in the so-called Fixed ACPI Description Table, which is the one that "auto-configures" the BIOS during boot .

What is the solution? Simple.

1.- I opened a terminal and wrote:

gksu gedit / etc / default / grub

2.- Locate a line similar to the following:

GRUB_CMDLINE_LINUX_DEFAULT = "quiet splash"

3.- Replace it with one like this:

GRUB_CMDLINE_LINUX_DEFAULT = "quiet splash pcie_aspm = force"

4.- Save the changes and enter the following command in the terminal:

sudo update-grub

This enables ASPM no matter what the BIOS says, and tests show that this solution achieves remarkable power savings that significantly increase battery life.

Source: Phoronix & Very Linux