The game of the century and proof by contradiction

The Game of the Century is a chess game between 13 year old Bobby Fischer and Donald Byrne, played in 1956. Byrne was an established player, and had won the US Open championship in 1953. Although Fischer's star was rising, Byrne was considered the favorite. Byrne, immaculately dressed, in a suit and tie, sits with a cigarette between his fingertips.

The opening moves in chess, pretty much fall into set patterns until about move 10 or 11. Then in a few more moves, something called "novelty" happens. This is when the chess game evolves into a unique position; one that has never ever before been played in this history of humanity. This is a combinatorial fact. This is where the game of chess leaves "the book", and the players must innovate.

Byrne opens the game with Nf3; a pretty nondescript opening that evolves quickly into something called the Gruenfeld Defence. This is a fairly well known chess opening. Fischer defends based on "hypermodern principles", inviting Byrne to establish a pawn stronghold in the center that he will attack in the mid-game.

10 moves pass, and they're pretty evenly matched. On move 11, Fischer offers a knight sacrifice. There is usually a person recording chess games in chess notation. Fischer's knight sacrifice is usually written as

    11 ... Na4!! 

"On the 11th move, black moves knight to position a4 on the chessboard". The two exclamation marks at the end indicate that it's a very interesting, delightful move that has strong consequences in favor of the mover. Byrne, the consummate chess master, wisely says "No thanks!" to Fischers clever ploy.

On moves 16 and 17 Byrne threatens Fischers queen. Fischer is in trouble now. He has problems with his queen, and stands to lose a knight if he protects his queen. Instead, Fischer moves Bishop to e6. Fischer does not protect his queen; instead, he moves his bishop and offers his queen up as sacrifice. This is considered the greatest move in all of chess history.

One can imagine Byrne dragging hard on his cigarette, inhaling deeply. "What's this kid doing?" After some thought, Byrne takes the queen. After that Fischer begins a windmill - a series of discovered checks - that wins him a a rook, two bishops and a pawn for his lost queen. Experts say that after this move, there is nothing that white could have done to recover.

Proof by contradiction, in GH Hardy's words (see A mathematicians apology (1941)), is much like a chess gambit. He says,

    Reductio ad absurdum, which Euclid loved so much, is one of a mathematician's finest weapons. It is a far finer gambit than any chess play: a chess player may offer the sacrifice of a pawn or even a piece, but a mathematician offers the game. 

I find this a very appealing metaphor. I was listening to radiolab's podcast (Games) which talks about The Game of the Century and was reminded about Hardy's quote about chess and proof writing. Of course, the process of doing mathematics has nothing to with playing chess.

Lenovo Thinkpad T450s Review and Linux (Arch and Ubuntu) install

A good linux ultrabook: Thinkpad T450s

Table of Contents

• Overview
• Selecting a Laptop
  • Requirements
  • The Candidates
  • My Final Choice
• Installing Linux
  • Design
  • Arch Linux
  • Ubuntu-Gnome installation
  • Running Installation notes
  • HiDPI screens
  • My thoughts when deciding on a laptop

Overview

I've been looking at a decent laptop to travel with, since it seems like I'm going to be traveling to:

• Illinois
• Toronto
• Leipzig
• British columbia

in the next three months. Due to the nature of my job -- I do research in a university -- I find that traveling without a full fledged computer can be a little crippling. I wrote my thesis on a chromebook hacked to run linux; now that I'm no longer below the poverty line, I have no more excuses. I must suck it up and shell out some money for a new ultrabook.

So I'll cover my selection process, and the installation of two flavors of linux on my system.

Selecting a Laptop

Requirements

• Runs linux without too many hiccups: ubuntu certification is a good indicator of this.
• Light, at most 3.5lbs.
• Nice screen, preferably IPS, at least Full HD (1920x1080) with, optionally, a touchscreen. UPDATE: the touchscreen is not that useful really, I wouldn't get one if I bought a computer again. It's nice to have on the rare occasions that I actually use it.
• Runs in clamshell mode
• Backlit keyboard is essential.

The Candidates

I had several candidates initially. I'll copy paste directly from my notes at the time, so they will be a little terse and badly written.

• Lenovo T440s: The T440s has good linux support, and a great keyboard. The only bad part is the sucky mousepad. It's sleek and has a good VGA port. It's only 0.8" thick at its thickest, and weighs 3.5lbs. It has a full port selection and includes a VGA port. Can also get the 1080p screen with IPS. Can also get a touchscreen, but this is probably not as useful. Screen options include
  • 1080p no IPS
  • 1080p IPS
  • 1080p multitouch with anti-glare.
    A refurbished T440s from the Lenovo website with the multitouch IPS screen is $780.
• Lenovo T450s: This is a great machine. There are a bunch of options and you can upgrade everything important, including the SSD and the RAM. The IPS multitouch display is also a bit cheaper on this one. It has a full range of ports, but it does weight a bit more than the X1 carbon. The keyboard is also said to be a little better than the Carbon since it has more travel.
  There are potentially three m.2 slots if you choose to get the one without the smartcard reader and WWAN card. The most basic model comes with a 16BG NGFF (next-gen form factor) m.2 ssd, and a 500GB harddrive the i5 5200U and 4GB of ram. This costs about $900 for the base model.
• Lenovo T430s: Has a 1600 x 900 display. Screen options include 1366 x 768 and 1600 x 900. No IPS panels. It's about 1" thick at its thickest, and weighs about 3.5lbs. It potentially has a 9 hour battery life with the optional 6-cell battery. It also has a DVD reader, which nobody needs anyway. More detailed specs can be found here. Some youtube videos like this one compare the T430 and T430S, and they appear to be almost the same; the T430S is marginally lighter. The T430s has a backlight that you can adjust. You can also get a reading light on it. The 430s has a NVIDIA NVS 5200M, which is a kind of shitty GPU. Reviews appear to say that its much worse than most other GPUs. It does not have a fingerprint reader. aside: for some reason, I seemed to have become obsessed with fingerprint readers at the time; probably for the coolness factor.
• Lenovo T431s: Exactly ".8. Almost the same as the T430s including the screen, harddrive, processor and other essentials. Smaller battery, only 3cell. But it has a new U series processor, which is a low Haswell processor with low power consumption. See tech specs. One major difference is that the touchpad has the mouse buttons built in, and this is very annoying. Some people say that the keyboard is not as nice on this one.
• Lenovo X230: This has a VGA port, mini display port with audio (which can convert to HDMI if necessary). Smart card, fingerprint, 2 USB 3.0. Both the IPS and TN display have the same resolution. So maybe this is good enough. It's hard to tell which one is the IPS display and which one is not sometimes, but you can get the serial from the seller, and do a specs part lookup. There were also some screen issues in this generation, where the AOC panel was much nicer than the LG made panel. It's about 1.25" thick at its thickest (my acer chromebook is about 1.10" at its thickest). Only 3.3lbs. 9 hour battery life. Supposed to have a fantastic keyboard. The IPS is much better thant the 430s TNs screen where it comes to distortion. It may or may not have a backlight; not all keyboards were built with one. The X230 has a slightly cramped palm rest too.
• Lenovo X240: Has VGA port, 1080p screen, less than 3lbs. But annoying trackpad and everyone does not like it. It's about 0.8" thick throughout. Can get upto a 1080p IPS screen, but its only 12.5". Can also get a touchscreen with this one. You can get a refurb like this one with an IPS screen and 128GB ssd for $714.
• Lenovo X250: Comes in next month (I wrote this in January). Again, it has a low res screen by default, but the new trackpad is probably back. Maybe I should stick with the X230 or the T430s for now. The X250 still has a nice port selection including a VGA port.
• Lenovo X1 Carbon Gen 1: It has the old touchpad with buttons. Only a 1600 x 900 screen. No VGA. Nice and thin at 0.75". Only $690 though. The x1 carbon vga dongle is only $35 though. Reviews say that its a fantastic keyboard and mouse. Some people say that this had build quality issues. It has a miniDP, combo audio, USB 2.0, USB 3.0 and 4-in-1 card reader. Ethernet is via a USB dongle. It has a glass touchpad. It's only 0.74" thick - this is about the same as the Yoga 2 or 3, which I've actually seen in stores. It also has a fingerprint reader. It has a 14" screen. It's about the same weight as the x230. I don't know if you can get a docking station for the x1 carbon. There is a dock for the X1 which give 2 USB 3 ports and 2 USB 2.0 ports. The x1 gen 1 uses the SFF ssd, 22x80mm less than 3mm in diameter, and I can replace this with a large capacity ssd in the future. tech specs. There is a video here comparing the t430s and the x1 carbon: Same keyboards. The screen looks better on the carbon. The touchpad is better on the carbon. There is a backlight on the X1 carbon. The x1 carbon has a low voltage processor, and is slower than the T430J. Here is some more discussion about the X1 Carbon versus the X230.
• Lenovo X1 Carbon Gen 2: 128gb SSD, 14" QHD display, i5 to i7 processor. No VGA port. HDMI, mini-DP. It's an extra $60 for a minidp to vga, but it does come with an ethernet adapter. It has 2 USB 3 ports, and no SD card reader unlike the Gen 1 Carbon. It does not get good reviews though. It has the annoying clickpad like the X240 and T440. Low battery life, but good display, no vga. It's very durable. The gen2 keyboard felt not as nice as the 440s and the X240. It has a relatively slow SSD, but that's not a big deal either. Most people say very buggy, do not buy. There is a newer key placement that is a little annoying: turns out that the function keys have been replaced by an touch sensitive band that changes key functions dynamically.
• Lenovo X1 Carbon Gen 3: great everything, but it has 2 USB, 1 miniDP, 1 HDMI, an ethernet miniport and no SDcard reader. Can get these separate I suppose. The display is great, and so is the touchscreen. The ethernet extension adapter is included in the box. Amazing keyboard. A video review is also available.
• Lenovo Yoga 14 Thinkpad. Good size screen, looks pretty good. The keyboard is comparable to the macbook pro. The mouse is a little annoying with its springyness, but it's ok. It does not have a VGA port, is about 0.8" thick. Reasonably heavy. It had a 1080p IPS touchscreen. It was priced at about $1000. It was very snappy to use. It also had a graphics card, which seems quite good. But its supposed to have bad battery life. It also has a touchscreen. It weighs a good 4.2lbs, which is not unhefty. The display rotates and it also becomes a tablet. It does not have VGA output. It also has an NVidia 840m. The 840m is pretty shit.
• Lenovo Yoga 2 Pro: Good looking, high resolution (QHD), but no Thinkpad brand. About $733 at the outlet. Since it doesn't have the Thinkpad brand, I suspect it might not have the nice keyboard,
  and I think this was confirmed in a visit to Best Buy.
• Lenovo U530: Another Yoga 2 pro like computer. It's supposed to be an ultrabook. Full HD screen 1080p. i5 processor, hybrid drive. Only $536. I have no idea how this is different, but it seems that its not a Thinkpad, which might make its construction a little cheaper.
  There are pages which attempt to do this. But the problem with the first generation carbon is that it has quite low battery life.
• Dell XPS 13 ultrabook: People also consider the Dell Ultrabook 13 as a good linux laptop. The previous generation (2013 and earlier) XPS 13s had a developer edition with hardware that was completely compatible with linux. I was not very impressed with the keyboard, if I remember correctly. The older version didn't have very good screen resolution. It is noisy when running hot, and has poor battery time. Some people complain about some coil-whine type issues with the 2013 and older versions. These retail for about $1000.
• Dell XPS 13, 2015 edition: The 2015 version is supposed to be pretty good. It had great reviews in CES 2015 show, especially about the nearly bezel free screen. This was a strong contender for a while, but I heard that they were having a lot of hardware compatibility problems in linux.128GB ssd, $800 on dell's site for the i3 and $900 for the i5. It has a 1080p screen. Specs are: backlit chiclet keyboard, 2 USB ports, 1 minidisplay port, and 1 headset jack. Note that you can buy a USB hub too to help with the lack of USB ports. There are several versions of the new Dell XPS 13s you can buy. The microsoft signature edition is cheaper than the one on the Dell website, and does offer some sort of educational discount. It has a media card reader, and weighs about 2.6lbs. The 9333 which is available for about $800 on dell's store is the one with the coil whine issue. The newer one is called 9343, which is the sleek one.
• Samsung ATIV book 9 ultrabooks: They look very sleek, the screen is fabulous and they have good linux compatibility. I've seen a friend using linux on it too; he even had Skype running. There are two versions: the lite which is an AMD based piece of shitty plastic with a 128GB ssd and a 1366 x 768 screen. Then there's the plus, which is in beautiful brushed aluminium, and has a QHD (3200 x 1800) screen. The lites are available new for about $700 and refurbished for about $600. The pluses run in the $1300-1500 range, but there did seem to be one on Amazon for about $1000 at some point. It has an i5, and 128GB ssd, 4GB ram, a QuadHD screen, dongle for VGA, microHDMI, 2 USB 3.0, SD card reader, and is just 0.54" thick and weighs 2.56lbs. Good battery life. Has a 1 year warranty. Only a 90 day warranty for the refurbished. It's a decent option. At some microcenter its avialable for $550. That's crazy. Here are some arch install notes, that indicate that linux support is quite good.
• Acer Travelmate P645 series: is a business oriented laptop that's supposed to be good too. 256gb ssd, 8gb ram, Radeon gpu, Intel wifi and Matte hd screen. About $1200 has a GPU and so on. Has a fingerprint reader. it also has a VGA output, and is made of carbon fiber. This is a very strong contender.
• Asus Zenbook UX301: pretty expensive at around $1300. It does have nice specs and looks nice too. It's the previous generation, but is still pretty expensive.
• Asus Zenbook UX303LA: about $850 on amazon. It has a 1920 x 1080 screen, 13.3 inches.It has an i5 U processor, 128 GB ssd. 3USB, 1microHDMI, 1minidisplay port, bluetooth. But they have a yellowing problem with the screen. This is well documented in reviews, and some people say that they've fixed it in samsung's version of the screen. Also has a full sized HDMI port. There are linux driver problems since the trackpad is a focal pad, and it has very basic support through linux's evdev driver.
• Asus Zenbook UX302LA: $700 at nomorerack.com. Seems like a good deal for the previous version. There is only a 90 day manufacturers warranty.
• Asus Zenbook UX31A: It comes with all the cables as standard despite having only a small selection of ports. It also has a FullHD multitouch screen. There is some backlight bleed. People complain that there are durability issues with this one.
• ASUS Vivo book S400ca-DH51T. It's 14in, has a hybrid drive, 1366 x 768, i5 processor. Weighs 4lbs. A newer version is the V451, but these things are quite heavy, running about 4lbs.
• Asus 2-in-1: $700 at best buy. Basic, does not appear to have display port.
• Asus Zenbook prime: UX31ADH51 or whatever sells for about $700 on ebay. It's new and not refurbished and comes with a warranty. The newer asus zenbooks are the UX303 and the UX32A. These are newer than the UX301 and the UX31 series respectively. It appears to work very well with ubuntu, and is, in fact, ubuntu-certified. It has a 1080p IPS display, and the battery life is supposed to be very good. It's about $760 on beachcamera.com (refurbished) only comes with a 90 day warranty. Some people say that the design is kind of flimsy. Some people say there is screen glare, and in particular, the matter screen of the X1 carbon is much better for this.

  Some more sites like buydig also sell with 90 day warranty for $750. Some people returned it and bought a macbook air because the HDMI port had bad build quality.

• Macbook Pro 2015: The macbook pro has a fantastic looking screen, and a beautiful keyboard. Seems like it will be a little painful to use linux on it. The base model is about $1300, but it only comes with a 128GB ssd. If I got the 256GB ssd, the price jumps to about $1500. There are linux problems on macbooks that are very annoying: wireless card, weird custom EFI, webcam doesn't run, etc, etc. It is beautiful, but the beauty is only skin deep (Arjun, you've made this mistake before, don't make it again).
• Macbook Air: its only .68" thick, and has very good specs for the price: about $1100 for the one with the 256GB SSD. Again, this is a pretty strong contender, but the screen isn't half as nice as the Pro, and the bezel is kind of ugly.
• Macbook Pro 2014: The refurbished ones run about $1000. Has a retina display and 256GB SSD. This was released in Feb 2013. However, running linux on it is a hit-or-miss. What doesn't work is suspend resume, iSight, speakers. Even the webcam does not work, which is kind of annoying.
• HP spectre 13: also good battery life.
• HP Folio: the old generation with the shitty screen is about $350 used or refurbished. It's heavy, but workable.
• Acer Aspire V7 Nitro which has a nice graphics card etc, but it weighs about 5lbs.
• Other contenders: also consider the Dell Precision Series, which are workstation class, have great configurations, but are rather heavy. The Dell Latitude E7450 which sells for about $1200 for a good configuration. They say that the latitudes have good keyboards. I've seen a friend using the HP Elitebook 840 G1. This reddit thread has a few more good suggestions.

My Final Choice

It finally boiled down to the Dell XPS 13, the T450S, and the X1 Carbon. Once I found out that people were having a lot of trouble installing linux on the Dell, I decided to go with Lenovo, since the X4X series of thinkpads had good linux support. The thinkpad community is also pretty supportive, and I've heard that Lenovo is pretty commited when it comes it Lenovo support. This ruled out the Dell.

Then I called Lenovo, and it turns out that they gave pretty good educational and business discounts. I got quotes for a highest spec X1 Carbon 3rd Gen for about $1100, and a high spec T450S for $1000. Now I had to decide whether I wanted the sleek looking, light X1 Carbon over the heavier, but more functional, upgradeable T450s. I went with the T450s since I figured I'd need the extra ports -- I make presentations on VGA projectors -- and because linux doesn't have great HiDPI screen support. You may object and say that cinnamon and gnome do some screen scaling, but they only scale to integers, unlike the Mac screens. They do this scaling by doubling pixels usually - each pixel becomes 4, and although your picture remains sharp, you lose quite a bit of screen real estate. In other words, the 2560x1440 screen on the X1 Carbon would scale down to 1280x720; my screen would be have the same effective area as a 720p screen. However, a native 1080p laptop screen is just perfect for a 14" screen. If you do choose to go with the X1C, check out this article about using xrandr to get perfect pixel doubling in linux.

People also said that they barely use touchscreens; I've enjoyed mine so far, especially when I'm lying down in bed and watching a movie or reading a pdf. UPDATE (Apr 11 2015): I barely if ever use the touchscreen. But I still like having it.

Installing Linux

Design

I wanted to boot three operating systems: Ubuntu, Arch and Windows. I also wanted to share my home directory, dropbox, vim directory, and usr/local between the two distributions. The best way to do this, I found, is to use Logical Volume Management or LVM. It's extremely simple to use, and a huge convenience: you create one large partition as a physical device, and create several logical volumes inside of it that you can dynamically resize, even as your system is running.

I've found that LVM2 is very stable, and extremely useful. I highly recommend it. I've even extended by root filesystem on lvm without unmounting it. Isn't that neat?

I decided that I would have the following volumes

I wanted to have one common home directory, but I'd be using two different desktop environments on ubuntu and arch, so I was warned about incompatible ~/.config files.

Quick instructions

• Booted into arch using a my multiboot stick, and made a large lvm using parted. Create the partition using mkpart, and then turn on the lvm flag in parted using

[code lang=text]
set <part num> lvm on
[/code]

• Then use the pvcreate, lvcreate commands as described in the arch wiki. All partitions can be made using lvm including swap. I think the boot partitions can be inside the roots of each individual distro. swap space must be formatted with

[code lang=text]
mkswap /dev/vol1/swap
[/code]

Arch Linux

Networking

Network manager under Cinnamon is pretty shitty by the way. It was hard to save profiles: I thought it was because gnome-keyring wasn't installed, but this didn't seem to the problem. The problem appeared to be the cinnamon version of nm-applet. Also, Network Manager didn't refresh the list of networks quickly enough, and I found this a bit annoying.

So I tried netctl and netctl-auto for a while, but this is a bit of a pain. You need to download specific profiles for eduroam, and its not quite clear how to configure them a priori. Trying to configure your internet while getting help online is a bit of a pain, as you can imagine.

Then I tried connman and connman-git. These were ok, and connected fast. However, connections were unstable, and notifications were unreliable. I then tried wicd, and was quite unhappy with this too. Although configuring wicd was easier than connman and netctl, it still had connection issues.

However, the connection issues appear to be related to the iwlwifi driver in the 3.18 kernel I'm running. See my running notes on the install for kernel patches, fixes and more info. This is still not fixed, but I'm very happy with the 3.16 kernel on the Ubuntu side, which does not have these connection issues. I've not solved the connection issues on the Arch side, and will get back to it when I have the time.

In the end, suffice it to say that I went back to Network Manager.
This is why I chose it over the others:

• Easier to configure. No problems connecting to WPA2 networks like eduroam.
• Fairly stable.
• Great notifications.
• Automatically switches between ethernet and wifi.
• Scanning issues: I fixed this by manually running

[code lang=text]
sudo iwlist wlp3s0 scan > /dev/null
[/code]

which automatically refreshes the Network Manager list.

• Easy creation of ad-hoc networks. In fact, I don't use a router at home anymore. An ad-hoc network using an old Realtek card running on infrastructure mode is more than enough for my 5Mbps --it's free-- connection at home.
• nm-applet issue in cinnamon: I edited /usr/share/cinnamon/js/ui/statusIconDispatcher.js and commented out the line

[code lang=text]
'nm-applet': 'network',
[/code]

Now the default Network Manager applet icon loads, and this is much more stable and usable, although it doesn't fit very well into the cinnamon icon theme.

Touchpad

The touchpad on the arch side worked out of the box, but it needed a little fiddling to get the synaptics driver to work instead of evdev. The trackpoint buttons don't work out of the box, but they work on later kernels (3.18 and 4.0, as far as I know). The touchpad can be disabled entirely using a kernel parameter at boot (see synic's blog).

I prefer having two finger scroll on the touchpad to a trackpoint. But configuring the touchpad to work correctly does take a bit of work. Originally, it was running my touchpad using just the evdev driver, which is a bit basic. So I somehow managed to get it to use the synaptics driver, which probably had something to do with the /usr/share/X11/xorg.conf.d/50-synaptics.conf configuration file I copied to /etc/X11/xorg.conf.d/50-synaptics.conf.

I was having trouble with the scrollspeed and mouse pointer speed. I tested different values using

[code lang=text]
xinput
[/code]

which gets a list of all devices with their numbers. Suppose the synaptics device is X. Then do

[code lang=text]
xinput list-props X
[/code]

I had to change

[code lang=text]
Synaptics Scrolling Distance (306)
Synaptics Move Speed (309)
[/code]

and a few others settings. The general syntax is

[code lang=text]
xinput set-prop X "Synaptics Scrolling Distance" "114" "114"
[/code]

Note that these property names are different from the ones you set your xorg.conf. The synaptics man page gives a mapping from the xinput properties to the options to be set in /etc/X11/xorg.conf.d/50-synaptics.conf. These have different names from the xinput properties -- god knows why. I've listed some of my values, in case some people might find it useful:

[code lang=text]
Option "FingerHigh" "30"
Option "FingerLow" "25"
Option "MaxTapTime" "180"
Option "HorizScrollDelta" "114"
Option "VertScrollDelta" "114"
[/code]

Display

The icons sizes and screen area in Cinnamon are just perfect for a 14" laptop. The HiDPI display is beautiful at 1080p native resolution. I'm glad I didn't get the X1 Carbon and QHD since I would have had to have scaled the display anyway.

The one thing that I'm having the most trouble with is multiple displays in my dock. Others have dealt with this issue before, and it appears to be solved in the >=3.18 kernels. Also see. There are links there to kernel patches that you can apply yourself. I've not tested these as yet. Maybe once I'm done with taxes.

Battery Life

The tlp and tlp-sleep package really helped reduce my idle power (which you can check using powertop) to about 5W. I get a battery life of about 7-8 hours using the two 3-cells in the T450s. This is good enough for me.

Power management

The gnome-powermanager and acpid work well with each other, except for hibernate. Here is what I did to enable hibernate:

• Edit /etc/default/grub and change the following variable

[code lang=text]
GRUB_CMDLINE_LINUX="quiet resume=<swap partition device>"
[/code]

• Install pm-utils, or just use the cinnamon hibernate option. Everything works perfectly.

However, do see my notes on xfce4-power-manager.

I did have trouble with suspend to RAM: the T450s would suspend nicely, but after 3-4 hours would go into some bios induced "deep sleep" mode that it would not wake up from. This is because Intel RapidStart was enabled in the bios. Once I disabled it, everything was fine.

I sort of prefer using pm_utils for suspend and hibernate. This is because I can run scripts before and after wakeup. For example, some DEs fail to rerun your xmodmap file after wakeup. This comes in handy if, for example, you've swapped the Caps and Control key like any self-respecting vim/emacs (you use Ctrl+[ for escape on your US keyboard) user.

Also consult this link for more information about enabling hibernate.

What doesn't work

• Multiple monitors (apparently fixed on kernels >=3.19) problems with dock.
• Trackpoint buttons and trackpad simultaneously (apparently fixed with kernel >=3.19).
• Bad wifi drivers.

Otherwise everything works. Fingerprint reader, webcam, trackpad, acpi sleep and power buttons. You name it.

Ubuntu-Gnome installation

I've been meaning to try Gnome3 for a while now. The installation process was much smoother, and much more streamlined than Arch. It does install a little bit of bloat, but I couldn't care less. Installation and configuration took less than 20 minutes. Here are some selected notes from my comprehensive running installation notes:

• The desktop was rather sluggish when I first installed it. Turns out that this has something to with Gnome3 version 3.10. Once I added the Gnome3 ppa using

[code lang=text]
apt-add-repository ppa:gnome3-team/gnome3
apt-add-repository ppa:gnome3-team/gnome3-staging
[/code]

Then I updated to Gnome3 3.12 and then the lagginess went away. Apparently Gnome3 3.10 used some older GTK libraries, and this was the reason it was laggy. See.

• Gnome has trouble with remembering enabled extensions. There are a bunch of patches for this, and a fix is in the pipeline for the 4.00 kernel. I did try manually patching gnome-session, but somehow the patches did not have the desired effect. I resolved this by writing a startup script (by putting it into ~/.config/autostart/):

[code lang=text]
[Desktop Entry]
Name=restore gnome extensions
GenericName=arjunscript
Comment=
Exec=gsettings set org.gnome.shell enabled-extensions "$(cat ~/bin/current-gnome-shell-extension)"
Terminal=false
X-GNOME-Autostart-enabled=true
Hidden=false
NoDisplay=false
[/code]

The gsettings command reads an extension list off the a file stored in my bin directory, and enables all the extensions on startup. A cron script updates the file with my current list of extensions daily.

• I was also looking into compiling a new kernel that would resolve trackpoint issues. I kind of like the 3.16 kernel because it has been so stable so far. I'd rather do this than upgrade to a newer kernel, because for example, I know the 3.18 kernel has issues with the iwlwifi driver. I have some notes about the relevant patches [here](#trackpoint woes).
• Gdm doesn't like to load the gnome-classic shell for some reason. I've always loved the classic shell, and I kind of like mate too. I do not know why this doesn't work.
• I moved to xfce4 version 4.10, and I've loved how snappy, simple and customizable it is. I'm so much more productive in it. The only problem was the battery and power management plugin. I installed the very very recently released xfce 4.12 and I've loved it so far. It's pretty, fast and beautiful. One issue I'm having is that xfce4 power manager appears to steer clear of suspend and hibernate protocols. I probably have to enable some policykit thing.

  xfce4-power-manager does not work so well with newer versions of upower (>=0.99) since upower has dropped a lot of dbus hooks (or whatever they're called). They're saying that a lot of power management is now systemd/logind's problem. So xfce4-power-manager --dump gave me
  Can Suspend: No
  Downgrading to upower 0.9.23 fixed this.

Running Installation notes

These are the notes I took when I was setting things up. They're a bit terse and I haven't really edited them. They were written over a period of about a month. Most of the important stuff here I've summarized above.

Arch Linux

I made an EFI, multiple boot USB stick that contained Ubuntu and Arch. The usb stick usually boots off of EFI and legacy bioses, which is a godsend. However, I had a lot of trouble getting it to install windows too; fuck windows. Here is how you do it:

Mar 06 2015 Making a dualbooting usb for arch and ubuntu gnome. It directly boots of the iso files you download from arch or ubuntu - grub2 is pretty cool. I'm using the instructions from
https://wiki.archlinux.org/index.php/Multiboot_USB_drive#Using_GRUB_and_loopback_devices

At the end of this, I ended up having a legacy and UEFI booting USB disk. However, I still had trouble with windows booting, but I think I know how to do this now using bcdboot. See.

• Make a fat32 partition thats about 200MB. This is your efi partition. Set the boot flag using parted.
• Make a boot partition for grub, and set the bios_grub flag using parted
• Make a root partition to hold isos.
• You can also make a separate ntfs partition for windows, but this is requires a little more effort. You cannot boot off the windows iso using grub. So you have to use grub to chainload the windows bootloader, and the windows bootloader has to be installed using bcdboot.

  The bios_grub partition can be about 10MiB, and does not need to have a file system. The grub modules and drivers are stored in a boot directory or partition which has to be fairly big - this can be your root partition under the /boot directory.

My USB drive output

[code lang=text]
Model: Kingston DataTraveler 2.0 (scsi)
Disk /dev/sdb: 15.6GB
Sector size (logical/physical): 512B/512B
Partition Table: gpt
Disk Flags:

Number Start End Size File system Name Flags
1 17.4kB 1078MB 1077MB fat32 boot, legacy_boot, esp
2 1078MB 1088MB 10.5MB fat16 bios_grub
3 1088MB 15.6GB 14.5GB ext4
[/code]

Then run

[code lang=text]
mount /dev/efi-partition /mnt/usb1
mount /dev/boot-partition /mnt/usb2
grub-install --efi-directory=/mnt/usb1 --boot-directory=/mnt/usb2 --target x86_64-efi --removable
[/code]

Then create grub.cfg as appropriate to your system. Then you can also install old bios grub files (for legacy) using

[code lang=text]
grub-install --boot-directory=/mnt/usb2 --target=i386-pc --recheck /dev/sdX
[/code]

The bios_grub partition does not have to be the first partition, and it need not be fat16. Remember that the grub menuentries in the above arch link assumes that the iso is in the same partition as the /boot directory.

What happens is that grub_install rewrites the MBR to boot the bios_grub partition. This reads grub.cfg from the boot directory and boots the right iso. If it boots in UEFI mode, then the bios loads the grub efi loader, which then, again, reads the grub.cfg file in the root partition.

This works perfectly on my lenovo thinkpad (presumably, this is the USB stick that works perfectly on the laptop).

Once I created the boot stick, I installed arch.

• I booted into arch, made lvm using parted. You need to create the partition using mkpart, then turn on the lvm flag in parted using

[code lang=text]
set <part num> lvm on
[/code]

The use the pvcreate, lvcreate commands as described in

[code lang=text]
https://wiki.archlinux.org/index.php/LVM#Installing_Arch_Linux_on_LVM
[/code]

All partitions can be made using lvm including swap. I think the boot partitions can be inside the roots of each individual distro. swap space must be formatted with

[code lang=text]
mkswap /dev/vol1/swap
[/code]

• wifi-menu will not connect to eduroam, but you can make a special eduroam profile using info from the netctl-eduroam package from the AUR, or looking at
  https://gist.githubusercontent.com/anonymous/ed16e3b191cf627814b3/raw/d476e0dddbc8920b855702737ff69c287e620c7b/eduroam-netctl
• Create mirrorlist by looking at the archlinux.org/mirrorlist for the best mirrors. Remember to sort by mirrorstatus, which tells you how up to date a mirror is.
• I mounted the dirs in /mnt and then actiavted swap using swapon /dev/vol1/swap
• Then you should run pacstrap; its a simple script. To see what groups can be installed, check out
  https://www.archlinux.org/groups/
  I installed base base-devel xorg xfce4 xfce4-goodies. I wanted to install cinnamon, but I changed my mind and installed xfce4. Maybe I wanted something light. I can always test out cinnamon at some point.
• Check your generated fstab to see if swap and home are mounted correctly.
• I got a warning from mkinitcpio that says that we might have no firmware for module aic94xx. To look into at somepoint.
• Picked a password that looks like (see Private notes directory) three words. This has more entropy than a alphabet + symbol + number password more commonly used. I don't know if this is really true, I read it on xkcd. But it ought to be easy to compute. Shannon entropy, right?
  $latex
  - \sum_i p_i \log(p_i) = \log(n)
  $
  If you use symbols + alphabet + numbers in a 10 character hard to remember password, this is about $latex \log(50^{10})$. If you use a three easy to remember words, each of about 10 characters, you have a 30 character word. This goes as $latex \log(26^{30})$. The point is that the entropy goes linearly in the length of the password, but only logarithmically in the size of your character set. Trivial observation.
• Installed grub from inside the chroot. Also installed efibootmgr fuse and os-prober.
• Check whether kernel is booted in uefi mode. This is important. Grub can keep its own boot directory in each root partition, no need to keep grub files in the efi partition.
• I chose to keep the grub files in the root part, not in the uefi part. There appear to be several directories in uefi:
  /EFI/Microsoft
/EFI/Lenovo
/EFI/grub_arch
  grub-mkconfig will give errors. It will give errors about not being able to load modules like lvmetad. But this is a problem of running grub inside a chroot; there is not /run directory there. Once you reboot, everything ought to work. Check this by checking your grub.cfg for all the relevant partitions. In fact, once you rerun grub-mkconfig from outside the chroot.
• Before rebooting, however, install wpa_supplicant, vim (or gvim), dialog and wifi-menu (although for some reason I could not find wifi-menu in the repos).
• Once I rebooted, Windows could not boot because I did not resize the windows partition correctly. Apparently parted and gparted work well when the ntfs partition is in lba mode. If not, they sort of mess up the windows partition. So I hit refresh or erase from the windows boot menu, which reset the boot loader default to windows in efi mode. The grub boot loader was there too, but I did not know how to set the default efi boot loader: efibootmgr from linux ought to reset this.
• So I rebooted into arch using the usb stick, arch-chrooted into my hard drive, mounted the efi partition, and ran

[code lang=text]
grub-install --efi-directory=/mnt/efi-part/ --bootloader-id=grub_arch --target=x86_64-efi --debug
[/code]

The --bootloader-id specifies the name of the directory under /EFI/ where the bootloader files are stored.

grub-install then stores the grub files under /boot/grub, and the efi file in the efi partition. You do not need to run grub-mkconfig. What it does is that it just resets the efi boot order. This is an alternative to the proper way, which is to use efibootmgr. The previous grub files were still under /EFI/grub_arch. It just reinstalled grub there, put the grub files in /boot/grub and reset the efi boot order priority so that grub is run instead. There ought to be another way to change this directly instead of rerunning grub-install. Ubuntu has an update-grub script. I wonder if that is any different.

• Network manager is pretty shit btw. It doesn't refresh things fast enough, and somehow I can't create profiles very easily. I'm tempted to install wicd instead. I looked into the network manager refresh networks problem, and there appears to be no way to set it manually unless you rewrite the network manager code. This is a project by itself. Network manager is installed with the networkmanager package. It has to be enabled as a service.

[code lang=text]
systemctl start NetworkManager.service
systemctl enable NetworkManager.service
[/code]

Netctl has to be disabled first. Once NetworkManager is enabled, it pretty much takes over and netctl does not work.

• Unfortunately, cinnamon requires network manager. But you can still disable it as a service and use wicd instead. This is what I'm going to try. I tried wicd, but it had trouble with eduroam. Once I installed the widc-eduroam profiles into the wicd folder, I ought to have better luck. I will try this at somepoint when I'm having trouble with network manager. I don't know why cinnamon is having trouble with it.
• I'm also having trouble with superfast scrolling in the synaptics driver. But it does not appear to be loaded as a kernel module. The evdev driver is loaded though. xinput does recognize a synaptics device.
• I ran

[code lang=text]
xinput --list
xinput --list-props <device num>
xinput --set-prop <device num> "libinput Tapping Enabled" 1
[/code]

Now tapping works.

• gnome-keyring has to be installed for network-manager to be able to store network passwords. The cinnamon network-manager applet still does not work, even after installing gnome-keyring.
• Dropbox has a setting that says "start on system startup", and this appears to be interfering with the systemctl dropbox daemon. I've disabled it for now using systemctl. I don't really know which is better, but systemctl can restart daemons that have crashed.
• Will check on synclient to see if its running. Then you can sort of set your touch sensitivity.
• Look into synclient error: couldn't find synaptics properties. No synaptics driver loaded?
• Look into Peter Hutterer's work on the synaptics driver.
• My Xorg.0.log lists

[code lang=text]
Adding input device SyncPS/2 Synaptics Touchpad.
Applying InputClass "evdev touchpad catchall"
Using input driver "libinput" for "SyncPS/2 Synaptics Touchpad"
[/code]

For the ELAN touchscreen, it says

[code lang=text]
No input driver specified, ignoring this device.
[/code]

• To fix my PS1: It shows my mounted lvm in \W as my username. It ought to show a ~, as this is my home directory.
• I like my terminal set to the solarized (dark) color scheme. Things work well with colors here.
• To fix colors in the xfce terminal.
• I decided on a local install of texlive. I think this works ok. Who cares if there is a little repetition. It is a big package.
• My installation so far is only 3.2GB. This is quite amazing in arch. Crazy. In any case, texlive is only 1GB. Matlab and others are more.
• Installed keys using ssh-keygen and then ssh-copy-id
• Arch has a nice manager that manages your local TEXMF folder pretty well. It also looks up packages you need and what not.
• To do: add multitouch support, add ubuntu gnome so you have a stable fallback.
• Having trouble with wifi switched back to netctl. Can also use connman, which is supposed to be quite good. If you're having trouble try adding the following lines to /etc/modprobe.d/iwlwifi

[code lang=text]
options 11n_disable=1
[/code]

There are other things to do here too if it doesn't work. For now the netctl seems to be working quite well. I'm getting the

[code lang=text]
iwlwifi 0000:03:00.0: fail to flush all tx fifo queues
[/code]

error. I don't appear to be having connection issues with netctl so far. But also, I don't think I've woken from suspend here. See
https://bugzilla.kernel.org/show_bug.cgi?id=48921
Apparently the bug is caused by NetworkManager trigerring periodical scanning (every 5 minutes). So you can try and disable_hw_scan=1. But this option appears to have been removed from the driver. There is a kernel patch for this:
https://launchpadlibrarian.net/186572769/0001-iwlwifi-dvm-drop-non-VO-frames-when-flushing.patch
The patch says that the mac80211 wants to ensure a frame is sent, it calls the flush() callback.

The patch was posted in 2014 October by Emmanuel Grumbach. This patch has been tested, and it appears to be working
https://patchwork.kernel.org/patch/5033871/
Some more patches here
http://people.canonical.com/~sforshee/iwlwifi/
Intel said that the firmware wont be fixed. See the comments in the launchpad.net comment section:
https://bugs.launchpad.net/ubuntu/+source/linux-firmware/+bug/1270808

• Adding acpi_sleep=s3_bios,s3_mode to my grub configuration. See the thinkwiki
  http://www.thinkwiki.org/wiki/Problems_with_ACPI_suspend-to-ram#Troubles_on_resumek
  There is more complete information here
  http://unix.stackexchange.com/questions/14494/screen-corruption-after-hibernate-is-there-another-way-to-refresh-the-x11-disp
  Also suggested to look into pm-suspend debugging. There is another link that produces my symptoms exactly:
  https://bugs.launchpad.net/ubuntu/+source/linux/+bug/659434
• Connman also has problems with bgscan setting in wpa_supplicant just like network manager. This causes frequent disconnects and instability. It might be best to go with a low-tech solution like netctl-auto. It does not need to be installed.
• My network interfaces are wlp3s0 and enp0s25. You can see the current ESSID your connected to using iwconfig.
• I've switched to netctl. It works for my purposes right now. It's a little cumbersome to work with, but it works. To use netctl-auto, install wpa_actiond and ifplugd. Then netctl disable-all and start both as services.
• Installed cryptkeeper. You can run it by moving the /usr/share/applications/cryptkeeper.desktop into the usual /etc/xdg/autostart/ directory since cinnamon is gnome based and supports xdg.
• Installed the tp-smapi package for setting battery thresholds in the thinkpad. UPDATE (Apr 11 2015): Apparently doesn't work on newer thinkpads
• Installed and enabled tlp and tlp-sleep service. Pay attention to the optional dependencies in tlp and install them.
• There is a cinnamon setting to allow cinnamon to scale icon sizes so it works better relative to panel sizes. This is very useful for a hipdi display.
• Removed the acpi_sleep kernel option. This was causing my system to not wakeup after waking up.
• Cinnamon keeps automatically starting up nm-applet. So I edited

[code lang=text]
/usr/share/cinnamon/js/ui/statusIconDispatcher.js
[/code]

and removed the line

[code lang=text]
// 'nm-applet': 'network',
[/code]

• It's not completely obvious, but the arch wiki page says that NetworkManger is started through dbus. You can mask something to stop NetworkManager completely. Run

[code lang=text]
systemctl mask NetworkManager
[/code]

There is a good troubleshooting guide on the archwiki NetworkManager. See
https://wiki.archlinux.org/index.php/NetworkManager#Disable_NetworkManager
I ought to try connman-git and maybe a netctl applet.

• I'm trying an applet called cinnamon-applet-netctl-systray; I edited the PKGBUILD and did some other stuff with it. I also tried cinnamon-applet-netctl-status. I don't seem to see them on the systray.
• Mathematica install. Copied from university fileservers (after getting legalities sorted out with nelson) and setup links in /usr/local/. This seems to be working nicely. Starts up in a second, thanks to this amazing ssd. Mmmm. All I need now is 32GB of ram. Unfortunately, this damn thing doesn't support more than 12. But I've heard that some people have successfully installed 16GB sticks in the extra slot. I could live with 24GB ram.
• pam_unix and pam_tally errors: there are a bunch of login errors, since pam_unix and others try to write to /var/log/faillog without root permissions. There have been arguments about this for a while. See
  https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=383889
  https://bugs.launchpad.net/ubuntu/+source/gnome-screensaver/+bug/227994
• Journalctl can be run with

[code lang=text]
journalctl -b -0
[/code]

To get results from the current boot. See
https://wiki.archlinux.org/index.php/systemd#Journal

[code lang=text]
journalctl --since "20 min ago"
[/code]

Use

[code lang=text]
journalctl -f
[/code]

to follow messages.

• The chrony user was not removed. So the pwck (password check) and (grpwk) commands check your usr and group files (integrity check). I prefer ntpd.
• Changed my synaptics settings to make the touchpad less sensitive.

[code lang=text]
xinput set-props 12 "Synaptics Scrolling Distance" "100" "100"
xinput set-props 12 "Synaptics Move Speed" "0.5" "1.5" "0.02" "0.00"
[/code]

where the move speed props are "min" "max" "acce" "deprecated". Also look into Horizontal and Vertical Hysteresis (although I can't seem to find these properties on xinput).

• It's easiest to set the timezone with the gui. You need the root password for this.
• More on synaptics: it seems that it makes sense to set the finger high carefully with a little testing. I dont think the pressure setting makes a difference at all.
• Apparently the iwlwifi driver is not very good in linux. The problems I've been having was not network-managers fault after all, but rather rather the iwlwifi driver's. People also say that the older iwlwifi drivers were more stable in the older kernels. I should check and see if the iwlwifi supports 7265 on the older drivers. Keep in mind that the thinkpad 440p card is a realtek 818b that does not have a linux wireless driver. The 7265 is supported since kernel 3.13.
• It seems that my wireless router sucked a little bit, so I was having trouble with connectivity. Now that I've set everything to b/g mode, the modem is working a little bit better. Actually no, it still sucks. So I got a nice little $10 wifi card off Amazon, and run my old laptop as a wireless router. This works amazingly well.

Ubuntu Install

• Installed, was easy to do a custom install.
• Everything works out of the box except suspend and hibernate.
• Downloaded configuration files from arjundesktop. There are a bunch of configuration files.
• Edited /etc/fstab and did a bunch of mount binds, especially my arch partitions.
• Copied .Xmodmap
• Copied other bash and other configuration scripts from other partition.
• The desktop does feel kind of laggy, for some reason.
• It does seem to be using less ram though.
• There is a problem with the dock not recognizing the VGA output. It's just mirroring the apple display.
• Created a package list from my other ubuntu install. Wireless works stably out of the box.
• Looked at the dropbox .deb file from dropbox.com and the direct download using

[code lang=text]
cd ~ && wget -O Downloads/dropbox.tar.gz "https://www.dropbox.com/download?plat=lnx.x86_64"
[/code]

• The deb file also seems to provide a package called dropbox, which replaces nautilus dropbox. This does not appear to work for me when run as a normal user. I cannot see the dropbox icon, unfortunately.
• Now installing skype. It has a bunch of dependencies. It seems that it requires a bunch of dependencies. It's easier to just install the ppa; add ubuntu partner repositories from archive.ubuntu.com as a deb. Then skype installs easily and works well. Do a

[code lang=text]
dpkg -I skype
[/code]

to get the files it installs. skype seems a little unwieldy and this version of skype appears to conflict with another one that I downloaded from the skype website. It's best to install from the ppa.

• Used the config tar file to quickly copy a bunch of things that I needed. Used the backupconfigs script that I have that does this.
• set hostname in the file. It was set correctly. /etc/hostname is set correctly.
• Installed gnome3 ppa. ppa:gnome3-team/gnome3. It updated some packages that didn't make it into the ubuntu 14.04 release. See
  https://bugs.launchpad.net/ubuntu-gnome/+bug/1386721
  See Dawid Lorenz observations. They're saying that they were having problems when in gnome 3.10 (and some in 3.12). Some people say upgrading to gnome 3.14 completely solves some of the sluggishness issues. My version is 3.10.4 right now.

[code lang=text]
ppa-purge -p ppa:gnome3-team/gnome3-staging
[/code]

• Now my gnomeshell is 3.12.2 and everything works.
• There was some font corruption in the gnome terminal. I ran

[code lang=text]
sudo fc-cache -f -v
[/code]

This appeared to have helped. Another thing to do is to look at

[code lang=text]
Option "Tiling" False
[/code]

in xorg. It also helped to suspend and open the computer again.

• Now I'm enabling hibernate. By doing the following:
  http://ubuntuhandbook.org/index.php/2014/04/enable-hibernate-ubuntu-14-04/
  Edit some files in some policykit.
• To do: fix hibernate. Otherwise things seem fine.
• Fix dock: does not appear to detect VGA. It detects VGA as a mirror of the display port monitor. This might have something to do with not receiving EDID data.
• To do: get Xmodmap to load on startup. Can also invoke this using an .xinitrc file. Quite easy to do.
• Making kernel 3.18.10 from kernel.org. Essentially followed the procedure described in
  http://cweiske.de/tagebuch/thinkpad-ultradock-screens.htm

  Since apparently the ultradock support needed to be coded into the kernel. I'm at the recompiling kernel drivers stage. He still has bugs where docking and undocking causes issues.
  There is some more information here
  https://wiki.ubuntu.com/KernelTeam/GitKernelBuild

  Have to make clean and remake the kernel from above to get both monitors working. In the meantime, I ought to go home, workout, and then cook. Then prepare for the match. And then talk to Shirl.

[code lang=text]
pmi action hibernate
[/code]

• It works! pm-hibernate works best. Also note that the hibernate file size can be obtained by catting /sys/power/image_size. This is usually set to 2/5 the size of the ram, and swap only needs to be a little larger than this. One problem with pm-hibernate is that it does not lock your screen or ask you to relogin. To do - figure out how to make gnome hibernate like in pm-suspend, but maybe through dbus or the GUI.
• Looking into trackpoint woes.
  Peter Hutterer has a blog post here. He basically says that the patches have been merged into the new kernel 4.00. There are four sets of patches.
  First patch the synaptics.c file. Then patch hwdb so udev detects the lenovo touchpad as a special case.
  Then patch libinput. So there are a bunch of diffs here too in dmitry's queue. It only appears to patch synaptics.h and synaptics.c. But Peter Hutterer's work also patches the synaptics.conf file. There is also a good overview of the bug here.
  Dmitry's patches appear to not require userspace changes, i.e., no udev changes? They appear to be a newer implementation of Peter Hutterer's work. So, to do: download the patches from dmitry's queue. Patch them into your kernel, and then recompile so that other issues with the dock video output are fixed too.
• To do: reduce your swap space again. You don't need so much to hibernate. Take it down to like 4 GB after looking at the /sys/power/image_size file to see how big the hibernate image is.
• Make the power button go to interactive mode when you hit it. I have no idea how to enable this.
• Enabling trim using the arch wiki. Says its preferable to keep relatime instead of noatime since some programs look at access time of files. I like this link more. It says dont use mount (and I don't mount physical volumes using fstab, only lvm volumes), but use fstrim instead. In ubuntu-gnome, there is already an fstrim script in /etc/cron.weekly
• Hurray! Hibernate works through the gnome menu. I think all it needed was the resume=/dev/vol1/swap kernel parameter.
• The gpu crashed on resume.

[code lang=text]
[42014.593037] [drm] stuck on render ring
[42014.594798] [drm] GPU HANG: ecode 0:0xc2852dd6, in Xorg [1421], reason: Ring hung, action: reset
[42014.594802] [drm] GPU hangs can indicate a bug anywhere in the entire gfx stack, including userspace.
[42014.594805] [drm] Please file a _new_ bug report on bugs.freedesktop.org against DRI -> DRM/Intel
[42014.594808] [drm] drm/i915 developers can then reassign to the right component if it's not a kernel issue.
[42014.594810] [drm] The gpu crash dump is required to analyze gpu hangs, so please always attach it.
[42014.594813] [drm] GPU crash dump saved to /sys/class/drm/card0/error
[42016.593049] [drm] Enabling RC6 states: RC6 on, RC6p off, RC6pp off
[/code]

I backed up the crash dump to dropbox somewhere.

• To do: fix the gnome shell extensions not being saved problem. UPDATE (Apr 11 2015): Fixed this with a script that uses gsettings to restore my extensions
• gnome-settings-properties appears to have been removed from gnome 3.12 and later. The gnome settings fix is here. There is a patch set out that fixes this. But the ppa for the patch is not useful, since it applies only to trusty proposed, and the version I have installed is from the gnome staging ppa. See below; I patched this manually, it appeared to work, but didn't.
• Suspend wakeup problems on lid closing are still there. Looking at
  http://www.thinkwiki.org/wiki/Problems_with_ACPI_suspend-to-ram
  See also
  http://www.thinkwiki.org/wiki/Problem_with_display_remaining_black_after_resume
  He also says, do not pass the ec_intr=0 parameter anymore. In fact, you're discouraged from using it. See this bug
  https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1331077
• My bios version is

  [code lang=text]
  JBET41WW (1.06 )
  [/code]

  My bios release date is

  [code lang=text]
  12/23/2014
  [/code]

  There is a bios update for me, so I should try it.
  http://support.lenovo.com/us/en/products/laptops-and-netbooks/thinkpad-t-series-laptops/thinkpad-t450s
  Apparently there is a problem with the intel rapidstart option, and this should be disabled in the bios. There is an updated bios for the E430/440, and no need to disable usb3.0. Released on 3-20.
  https://bugzilla.kernel.org/show_bug.cgi?id=80351
  It says update to USB 3.0 and then install the bios update. I did the bios update, but it seems like intel rapidstart was the culprit.

[code lang=text]
gsettings get org.gnome.shell enabled-extensions > file
[/code]

The make an autostart file in ~/.config/autostart with

[code lang=text]
gsettings set org.gnome.shell enabled-extensions "$(cat file)"
[/code]

You can also make a cronjob to update the enabled-extenions file. This seems to work better for me.

• To do: download the gnome-session package from the staging repositories and see if it has actually changed something. Right now, the my gnome-session does not save the extensions.
• Even gnome-do is working as long as I use startx. Sort of weird. But startx doesn't like to read the xsessionrc file. Startx does run ~/.xinitrc though. It can't grab the Super+space key since gnome greedily monitors it for the dash. However, gnome-do works with Ctrl+space. Which is quite good.
• My gdm doesn't like the gnome-classic shell for some reason. The errors are

[code lang=text]
GPU HANG: code 0:0x00f000c
Ring hung, action: reset
stuck on rendering
[/code]

• vim-gnome segfaults, sigh. And gnome for some reason ignores my

[code lang=text]
tb=
winpos
[/code]

settings. It definitely reads the .vimrc though. I can probably easily debug this by looking at the startup log. I think I discovered that the menu .vim files were loading after my .gvimrc

• Can you replace your old gnome-session with the new gnome-session version using apt-get?
• Moved to xfce which looks great and is easy to customize. Cannot use whisker menu very easily, but there is an easy way to find applications and what not. Gnome-do is kind of buggy these days anyway.
• GPM uses upower, which uses pm-suspend and pm-powersave. This means that its easy to run scripts on hibernate or suspend. This is a good blog post about this:
  http://vincent.bernat.im/en/blog/2011-gnome-power-manager.html
• Moved to XFCE 4.12 by adding the xfce-developer ppa. The only problem I have with xfce 4.12 is power management, since suspend and hibernate management are disabled. I believe this is a policykit issue, and can be resolved by changing some configuration files. In any case, suspend on lid closure and things like that are still handled nicely by acpid (or systemd). You do have to downgrade upower and remove gnome-power-manager to make xfce4 4.12 power manager handle lid closure and other events.

Miscellaneous Notes

HiDPI screens

Feb 17 2015 Now what I'm having trouble with is the HiDPI problem in linux. Should I get an ultrahigh HD screen or just a 1080p screen? There are problems in linux, but you can scale everything with xrandr.

• I learned a little bit about how apple renders at high resolution, and then scales the whole down using the graphics card.
• Linux solves this problem by assigning 2 pixes as 1 in each direction. Gnome and KDE have different approaches. But both methods require some fooling around with scaling. Gnome works very well in most situations, Cinnamon is supposed to have some good support, and KDE also has some support. The main problem is that X11 was not built to scale correctly. People think that this will be fixed in the coming Gnome
• xrandr can scale an external display correctly if configured correctly. It allows you to use a HiDPI screen with a low DPI screen external monitor if necessary. Here is a good script for this.
• There are two ssd slots on the T450s, both m.2 ssds. One is an ngff, which I'm supposed to get, if I want the third ssd slot. So if I get the third ssd slot, I can install an m.2 sata, on which I can install linux.
• Try adding "tearfree" to xorg if you get display tearing.
• Some guy also loved the 1080p screen so far, and hasn't had to do any special so far. He used

[code lang=text]
google-chrome-unstable
[/code]

and

[code lang=text]
static char font[] = "Terminus:pixelsize=18"
[/code]

Check out st. It's a new terminal of some sort.
See this guy.

• Mir is something that ubuntu is moving towards.
• Use this to fix the mouse temporarily.
• Some more information on display scaling.
• A stackexchange post on X11 scaling to virtual resolutions. It also comments on the fonts becoming blurry. Apparently fonts scale using bitmap, which is not good enough. When something has to be higher resolution, it really ought to be higher resolution; i.e., there ought to be a finer scale description of it. It's not enough to just double pixels, since this will look horrible.
• I really like this page too, which has a good description of scaling.
• This is also a good description of resolution on the gnome.org site which discusses apple's solution.
• This tested page has a great description of scaling. It recommends 1080p IPS on a 13.3" screen. The 2560x1440 is a bit too high to worry about scaling.
• I should look into the linux mint thing which does some pixel doubling, which might work. This scales the desktop by doubling pixels. Even this has a chance of not working since there was a guy who couldn't get xrandr to work. But it worked for a lot of people. It's pretty crisp like this.
• I should also see how pixel doubling works, and whether this will be good enough for me via the linuxmint xrandr trick.
• In 2013, this guy wrote an article about HiDPI scaling. He used KDE and use the nosquint plugin in firefox.
• I looked at a bunch of macbooks for display including the 13.3" macbook retina. It looks good, but not unbelivably good. The effective high resolution screen looked best, but it had small fonts. The icon sizes were fine, and if text size is increased (macs do not allow you to do this, but gnome does), things would work perfectly well. The effective resolution for the 2460 x 1600 mac display at highest setting was 1680 x 1050. The default was exactly half: 1280 x 800. It looked good, but not great at this resolution.

  The yoga 3 looked really good in windows (the text was a bit too small) at 3200x1800, and it scaled beautifully to 1920 x 1080. The screen real estate was also idea at this resolution. But it is a 13.3" screen, but its not much smaller than the 14" screen. 1080p looked fine even on the ASUS N550JK 15.6 screen, which was its native resolution. It wasn't great, but it was pretty good. It's an IPS panel as advertised on the ASUS website, but it wasn't quite clear. I think the 15.6" laptops can definitely benefit from 2460 x 1440 without scaling.

  I thought about half resolution scaling for the 2460 x 1440 QHD 14" screen, which is 1280 x 720. This seems like too little screen real estate, although it would look quite crisp since you can't see individual pixels.

  I guess hidpi works well for linux when you have a decent effective resolution when you halve the screen resolution. What's optimal for screens like 2460 x 1440 is a scaling like 1.5, which is not quite enough.

  But I must say, the old macbook which ran at 1280 x 800 is pretty bad. I did not like working on it.

Miscellaneous thoughts when choosing a laptop

Oct 04 2014 Also consider the T440s as a lenovo ultrabook. It's cheap, has a 14" display, weighs only about 3.6lbs. Has a good keyboard and seems to have better reviews that the X series. Also check this link out for thinkpad recommendations:nathan. People dont like the X1 Carbon since they've fucked up the keyboard. See. The mac for education 13" 1440x900 display is $950. That's pretty good.

Jan 22 2015 [laptop] Seems like I'll need this for travel, so maybe I should get one. I like the monitor though. So maybe I could use my laptop at home with the monitor. Does it work in clamshell mode? It does work in clamshell mode, it has a vga port. But the trackpad is annoying as hell. So maybe the x230 is a good machine.

Jan 25 2015 people comparing the t430s to the x230 liked both laptops but preferred the slightly higher resolution in the t430s. But the X230 only has a 12.5" screen. So perhaps the 14" t430s is better at a slightly higher resolution. There are some reviews on this forum. They also note that you can't get a webcamera if you get the 3x3" internal antenna; get the 2x2 instead. So I should also look into the msata thing versus the sata thing on the x230.

In this reddit thread, people say that the Lenovo IPS screen is better than the 2012 macbook air by far. The only thing is the size of the screen in the x230. This is one reason to go with the T430s: it's easier to see on this one.

Jan 25 2015 Some more reviews of lenovo laptops. It does the thinkpad yoga, the ideapad yoga 2 pro, and the x1 carbon. The x1 carbon first gen has a very very good keyboard, and a very nice touchpad, but has only miniDP out.

Jan 25 2015 [best buy, testing]

• macbook pro retina. About $1300, looks very good, decent keyboard. About 0.79" thick.
• macbook air: not such a good keyboard, but very light. looks ok.
• lenovo yoga 14 thinkpad. Good size screen, looks pretty good. The keyboard is comparable to the macbook pro. The mouse is a little annoying with its springyness, but it's ok. It does not have a VGA port, is about 0.8" thick. Reasonably heavy. It had a 1080p IPS touchscreen. It was priced at about $1000. It was very snappy to use. It also had a graphics card, which seems quite good. But its supposed to have bad battery life. It also has a touchscreen. It weighs a good 4.2lbs, which is not unhefty. The display rotates and it also becomes a tablet. It does not have VGA output. It also has an NVidia 840m. The 840m is pretty shit.
• lenovo yoga 2 and yoga 3. Bad keyboard with small backspace key. But very slim, nice looking. Great screens on some of them. I wouldn't buy these, the keyboard is too crappy.

Jan 25 2015 The lenovo thinkpad x230 is also certified for use with Ubuntu. Even forums say that macbook drivers are always funky for ubuntu. I read about problems with wifi and ethernet install. Also, it might be a pain to update the kernel inside ubuntu. You can remote to your server using VNC, which might be a fast way to run things off your desktop.

But that said, VMware also runs ubuntu in a macbook very smoothly. The only way to share things is to have a linux virtualbox and share things over samba.

Jan 25 2015 I'm also thinking again that the chromebook would be pretty good to have. I could test it out on my march trip to Toronto and then decide. Until then, maybe the desktop is a good idea to get.

Jan 25 2015 I'm leaning towards the X1 carbon or the X230.

Feb 13 2015 I'm leaning towards the X1 carbon 2015 or the T450s. I guess I'm ok with both, and I should be able to get either pretty soon. I did some more testing at the computer store, and the lower resolution display at 1920 x 1080 doesn't look as good on the Yoga 3 Pro. The higher resolution is pretty stunning and makes things easier to read. Again, touch is also quite useful to browse or scroll through papers.

How to debug problems on wordpress migrations

I migrated my blog from one server to another, and was seeing the usual white-screen-of-death on the http://blog.wordpress.com/wp-admin page. I tried enabling debugging with

[code lang=php]
define('WP_DEBUG', true);
[/code]

in the wp-config.php file. But this does not work on some webservers if some option (that I dont remember) is not enabled. So instead, I used the poor man's debugger: the print statement.

So I went into the wordpress/wp-admin directory, and started with the index.php file. I inserted

[code lang=php]
print('hello world');
[/code]

statements after each line, and then I'd reload the http://blog.wordpress.com/wp-admin page and see if the print statement executed. If it did, I moved the print statement further down the file to see what failed. I was able to finally trace this to a statement of the form

[code lang=php]
requireonce(dirname(dirname(__FILE__)). '/wp-load.php');
[/code]

which was not working as intended. The dirname(dirname(__FILE__)) statement is supposed to ascend to the parent of the directory of the current file. This was not working as intended. I just changed this to

[code lang=php]
requireonce('../wp-load.php');
[/code]

My dashboard started working again after I made this change!

A note to self about academic my academic plans from 2008.

This is reproduced in its entireity from a note I wrote in late 2008. I wrote it as if someone would want to read it; an informal statement of purpose.

A small, informal note-to-self sort of thing with a short description of my achievements and interests.

Some academic background

My interests have changed over the years and thought an outline of their evolution over time would be useful. My first academic “achievement” of note was a bronze medal in the International Chemistry Olympiad. It was a pretty tough selection process just to be able to represent the country: my school encouraged me to take the screening exams (three or four rounds of theory and labs) and four were selected from 104 applicants. I also got the "Best Experimental Work" award in the Indian National Olympiad selection camp.

I really enjoyed hands on, building-stuff-in-the-kitchen sort of work then and joined the mechanical engineering program at IIT Madras. I worked with Prof. Ramesh in the IC Engines lab on some interesting old-school hardcore engineering stuff in the first couple of years. I learnt a little electromagnetic theory, designed and built a solenoid-type linear actuator to move the control rack of a pretty large fuel injection pump, and wrote the control software (very basic PID kind of stuff) for the engine governor. This was a defense project for the diesel engine governing system on the “Arjun” (weird coincidence, no?) main battle tank for the Indian Army. It was great fun, especially as a freshman, to control this huge engine with just a little computer.
My interests started moving more towards theoretical problems and mathematics during my last year at IITM. I worked with Prof. Sujith in the Aerospace department on a model problem in gas dynamics. We obtained an asymptotic solution to the Euler equations for a particular type of inhomogeneity in the PDEs. Of course, being undergraduate work, it was neither very novel nor very sophisticated; but I did present the work in an AIAA conference here in the states and it was a good experience. However, I really enjoyed myself then and learnt a lot about nonlinear wave equations in general. My first introduction to dynamical systems and chaos was in my senior year as well - Prof. Balakrishnan taught the course and I kind of fell in love with the material. He covered an insane amount of ground in the course, Linear Algebra, Group Theory, nonlinear ODEs… the works. He was one of the best teachers I’ve ever had. You might have read his foreword (for the Indian edition, at least) to "Feynman’s Lectures in Physics" ...

At the University of Michigan, I worked with Prof. Bogdan Epureanu on a biological problem. We modeled the motion of motor proteins: these are little agents of transportation that carry cargo from one place in the cell to another. Since their size is of the order of nanometers, the Reynolds number of the flow around it is really low (Purcell, Nobel laureate, inventor of NMR, gave a beautiful talk on the movement of bacteria that is oft cited in the literature). This means their motion is overdamped and inertia plays no part in the dynamics. One might think that this makes their dynamics less interesting, but the motor protein’s small size implies that it is considerably affected by “thermal fluctuations” or collisions with the molecules in the media and works in very random environment. It turns out, that these fluctuations are essential to its operation (like Feynman’s Brownian ratchets). All this stuff makes this a really interesting problem physically and mathematically. So I taught myself stochastics – it’s not my adviser’s field of expertise – and did some interesting analysis on the problem. My adviser presented at a paper at a conference, and I’m writing another right now. I’ve attached my thesis and the conference paper if you’re interested. Oh, yeah, almost forgot – The College of Engineering awarded me the 2008 William Mirsky Memorial Award for outstanding achievements in research and academics.

Comment in 2015: In fact, it's a very interesting question: given a Brownian particle moving in a periodic potential, what is its effective speed of travel. This is a question answered by homogenization theory in dimension one. By some strange quirk of fate, I study this sort of thing now.

Future Plan

A year into my masters program, I knew I wouldn’t stay on for a PhD working the current problem I was working on then and told my adviser that I would quit in a year. I also realized that I lacked formal training in many fields of mathematics although I’ve picked up enough bits and pieces over time to apply it fairly competently in most fields of engineering and physics.
I decided I wanted to move to an applied mathematics program where I could consolidate my mathematical knowledge in a formal setting, even though my adviser expressed his interest in continuing to work with me and gently cautioned me of the impracticality (stupidity) of my choice. I would like to work on a hard, physically inspired mathematical problem in an interdisciplinary kind of environment. That is, I’d ideally like to have a one adviser in mathematics along with another in a science department – this, I believe, would be the ideal situation for a person with my skills and interests.

My fields of interest include complex and dynamical systems, pattern formation and emergent phenomena in such systems (very little background in this), wave equations and fluid dynamics, biological problems and probability. I do admit that this is pretty broad and I do not know what specific problem I would like to work on. However, I do believe that I should be able to figure this out in the first couple of semesters of the PhD program.

A funny mathematical quote

It's a curious fact (Dirichlet's theorem) that the prime digits are uniformly distributed among the odd numbers. There is a related quote

    All primes are odd. Two is the oddest.