GRUB
I've passed the following Linux parameters via GRUB's
/etc/default/grub:
GRUB_CMDLINE_LINUX_DEFAULT="quiet pcie_aspm=force i915.semaphores=1 i915.i915_enable_rc6=1 i915.i915_enable_fbc=1 i915.lvds_downclock=1"
i915.semaphores=1: "Enablement of semaphores solves several
stability issues on Ivy Bridge graphics cards, such as GPU hangs, and
improved stability and performance on Sandy Bridge generation of
graphics cards". See Intel 2011Q4 graphics
package for more details.
Wireless
I've experienced instable wireless, often it would just seize to function. The bug is described here on Intel Linux Wireless
To remedy the problem, I did the following:
# echo "options iwlwifi 11n_disable=1" > /etc/modprobe.d/iwlwifi.conf
# update-initramfs -u
Since I don't like rebooting when I really don't have to, I did the following to activate the changes:
# modprobe -r iwlwifi
# modprobe iwlwifi
Detailed information about the wireless card:
03:00.0 Network controller: Intel Corporation Centrino Advanced-N 6205 (rev 34)
Subsystem: Intel Corporation Centrino Advanced-N 6205 AGN
Flags: bus master, fast devsel, latency 0, IRQ 48
Memory at f2900000 (64-bit, non-prefetchable) [size=8K]
Kernel driver in use: iwlwifi
Battery life
I've added the following to/etc/rc.local to enhance the battery
life. With these in place, powertop lists all the "Toggleables"
as "Good":
# Dynamic power save
iw wlan0 set power_save on
echo 0 > /proc/sys/kernel/nmi_watchdog
# Enable SATA link power management for /dev/sda
echo min_power > /sys/class/scsi_host/host0/link_power_management_policy
echo min_power > /sys/class/scsi_host/host1/link_power_management_policy
# VM writeback timeout
echo 1500 > /proc/sys/vm/dirty_writeback_centisecs
# Sound power management
echo Y > /sys/module/snd_hda_intel/parameters/power_save_controller
echo 1 > /sys/module/snd_hda_intel/parameters/power_save
# Power aware CPU scheduler
echo 1 > /sys/devices/system/cpu/sched_mc_power_savings
