Debian 7 on the Samsung Series 9 Ultrabook

I recently purchased an upgrade to my aging laptop; a SAMSUNG Series 9 NP900X3C-A01US 13″ Ultrabook. I wont go too much into aesthetics except to say that this laptop is everything the reviews say it is. It’s light, sturdy, stylish, fast, and sips power. It is, almost down to the PCB, Samsungs answer to the 13″ Macbook Air. I am happier with it so far than I have been with any laptop I’ve owned… and I’ve owned quite a few.

At any rate, throwing Debian 7.0 (wheezy) on this laptop was trivial and almost everything “just works”. There are a few things I had to tweak as far as power saving, function keys, etc. and I wanted to outline those things here. Implement the items below to get the most out of yours if you own one.

Use the latest kernel
I am running 3.7.4 from kernel.org on this ultrabook. Always use the latest available stable kernel on laptops. This is doubly true on very new ones like the series 9 if you want all the hardware to be well supported. Some hardware wont work under the default wheezy kernel on this model. There are also continual improvements in power management happening in the kernel. One example of something that didnt work properly under the default wheezy kernel was detecting when the lid was closed.

Use tmpfs
Debian doesn’t yet default to putting some things on tmpfs that should be. In /etc/default/tmpfs set RAMTMP=yes to mount /tmp on tmpfs. I also like to add an entry to /etc/fstab to mount /home/someuser/.cache/google-chrome on tmpfs as well. Both of these things speed up access to temporary/cache data and help to save power.

tmpfs /home/someuser/.cache/google-chrome tmpfs mode=1777,noatime 0 0

Enable discard support
This laptop comes with a 128GB SanDisk SSD U100. If your SSD supports TRIM (and this one does) and you are using ext4 (and you should be!) you can enable TRIM support in the file system by adding ‘discard’ to all the mount points in /etc/fstab.

/dev/mapper/lvm-root / ext4 discard,errors=remount-ro 0 1

If, as in the example above, you are also using LVM then you should configure it to issue discards to the underlying physical volume. To do so, set “issue_discards=1” in /etc/lvm/lvm.conf.

Use NOOP scheduler
Schedulers are getting smarter these days so this might not be necessary any more. I am still in the habit of setting noop as the scheduler for non-rotational storage devices though. I like to add a udev rule that will set noop if the device advertises itself as non-rotational. You could just set the default elevator to noop but this would effect, say, a USB SATA disk that you may plug in some day.

cat > /etc/udev/rules.d/60-schedulers.rules << EOF # set noop scheduler for non-rotating disks ACTION=="add|change", KERNEL=="sd[a-z]", ATTR{queue/rotational}=="0", ATTR{queue/scheduler}="noop" EOF

i915 power saving
The i915 kernel module for the Intel HD 4000 graphics chip set supports some extra power saving options that you can take advantage of. To enable them, add the following to /etc/default/grub, in the same spot where the "quiet" option for grub currently exists.

GRUB_CMDLINE_LINUX_DEFAULT="quiet i915.i915_enable_rc6=1 i915.i915_enable_fbc=1 i915.lvds_downclock=1"

To see more information about what those options do, execute "modinfo i915".

Disable onboard LAN
This is a truly portable notebook. You shouldnt generally be using the onboard LAN a lot. You can save some power by disabling it in the BIOS.

Extend battery life
This laptop has such good battery life that you should be able to live with it quite comfortably in "battery extender" mode. This mode only lets the battery charge up to 80% and greatly extends the useful life of the battery. Enable it in the BIOS.

If you are in a situation where you know you're going to need maximum battery life (say, while waiting to board a very long flight) you can disable battery extender mode via a file in /sys. Letting the battery charge to 100% should give you about another hour of run time.

echo 0 > /sys/devices/platform/samsung/battery_life_extender

Enable touchpad tapping
Xorg uses the wrong driver for the touchpad by default. If you want to enable tap / doubletap / etc. then you'll need to touch a config file for Xorg.

mkdir -p /etc/X11/xorg.conf.d
cat > /etc/X11/xorg.conf.d/50-snaptics.conf << EOF Section "InputClass" Identifier "touchpad" Driver "synaptics" MatchIsTouchpad "on" Option "TapButton1" "1" Option "TapButton2" "2" Option "TapButton3" "3" #Option "VertEdgeScroll" "on" #Option "VertTwoFingerScroll" "on" #Option "HorizEdgeScroll" "on" #Option "HorizTwoFingerScroll" "on" #Option "CircularScrolling" "on" #Option "CircScrollTrigger" "2" #Option "EmulateTwoFingerMinZ" "40" #Option "EmulateTwoFingerMinW" "8" #Option "CoastingSpeed" "0" EndSection EOF

Coming Soon...

Enable silent mode binding
omething here about binding Fn-F11 to enable/disable silent mode.

Enable keyboard backlight bindings
Something here about enabling backlight keys Fn-F9 and Fn-F10

Enable wifi binding
Something here about Fn-F12

Turn off bluetooth radio by default
Related to the above, but only turn off bluetooth radio during boot up

Use Powertop
Something here about enabling powertops tunables on boot up