A few weeks ago I bought a new Samsung Galaxy Note 2 Android phone. As I predicted in my post about Phone and Tablet Sizes [1] the Note 2 with a 5.55 display is a bit too big for me to have an ideal single handed side grasp (I estimate that about 5.2 would be ideal). But I can stretch a bit and move it around in my hand to touch all parts of the screen with my thumb. Although when doing that I don t have a tight grip, with my previous phone the Samsung Galaxy S3 [2] I could properly wrap my hand around it to grip it tightly while using it with one hand. The Note 2 will be easier for me to drop or for a thief to snatch it from me. While the big screen makes the phone difficult to use with one hand it does allow viewing more data. The ConnectBot SSH client (Play Store link) [3] (F-Droid repository link) [4] works a lot better on a larger screen I ve also discovered that the volume control buttons can be used to change the font size in ConnectBot which is handy as the default is really tiny. Also Klaus Weidner s Hacker s Keyboard (Play Store link) [5] (F-Droid repository link) [6] works a lot better with a larger screen. When I tested the Hacker s keyboard on a smaller phone I found the 5 row layout too difficult to use, but on the Note 2 it works well. As an aside I wish I could quickly and easily toggle between 4 row mode (good for SMS) and 5 row mode (good for sysadmin work) in the Hackers Keyboard. For less serious use the large screen on the Note 2 is good for watching TV. I ve got a collection of mp4s of TV shows that I ve been meaning to watch, now I watch them in bed on my phone. Another advantage of the Note 2 is the battery life. When playing Ingress and doing all the usual email checks etc my Note 2 will last about as long as my wife s Galaxy S3 with it s power case. So without any extra batteries a Note 2 will probably last about twice as long as a Galaxy S3. The Note 2 has more RAM than the S3 I used to use (I had the S3 with 1G of RAM) and it also apparently has a faster CPU. The CPU speed hasn t been an issue for me but the extra RAM is a real benefit, it means that I can usually switch between Ingress and other programs without having to restart Ingress each time. As an aside I think that Google and LG should release a Nexus Ingress 4 phone or some other device that s optimised for Ingress, I m sure it would sell well. Some people make a big deal about the stylus that comes with the Note 2. It is a neat feature to have the device know when the stylus tip is hovering over the screen but it s not very useful for me. If I was going to create art work on a phone (as some people do) then it would interest me, but I m more interested in email and ssh for fine input and my fingers are generally good enough for those tasks. I have got thin fingers, so I think that people with thicker fingers could really benefit from the stylus. I recently bought a batch of stylus pens from Kogan which have a pen at one end and a rubber stylus tip at the other for fat fingered people I know who need to use an Android phone but can t afford a Note or Note 2. I also like the software build on it which is almost the same as that on the Galaxy S3. It seems that many people prefer the apparently stock features on the Nexus 4 but I like the way Samsung does things. Conclusion I m very happy with my new phone. The bigger screen allows me to see things more clearly, this is good for web browsing, reading email, and now that I can use the Hackers Keyboard I can type more effectively. The longer battery life is really good too, although I think that Samsung could have done better if the phone was 3mm thicker then it could have a much bigger battery and have a larger CCD for the camera. I don t think that the phone is really different, at least not for my use. Samsung has promoted it for artistic use and I ve seen evidence to support their claims. But for most people it ll just be a phone with a larger screen and a bigger battery. Some people criticise it for being too big, but it s still smaller than the handsets on most desk phones so it s not big by the standards of old fashioned phones. The increased size has not only allowed me to do the same things more effectively but also allowed me to do things I hadn t tried doing on a phone before such as watching TV. This isn t because of the phone being particularly special in any way, it s just that the change in size gives more possibilities for ways of using it. The Samsung Galaxy Mega is the largest smart phone. The 5.8 version of the Mega has a resolution of only 960*540 (less than the Note and Note 2 not good enough IMHO) and the 6.3 version has the same resolution as the Note 2 of 1280*720. I think that both Mega variants are too big for me, I need to be able to use a phone with one hand. So it seems that the Note 2 is probably the best phone for me right now.

• [1] http://etbe.coker.com.au/2013/02/11/phone-tablet-sizes/
• [2] http://etbe.coker.com.au/2012/12/21/galaxy-s3-power-case/
• [3] https://play.google.com/store/apps/details?id=org.connectbot
• [4] https://f-droid.org/repository/browse/?fdfilter=connect&fdid=org.connectbot
• [5] https://play.google.com/store/apps/details?id=org.pocketworkstation.pckeyboard
• [6] https://f-droid.org/repository/browse/?fdfilter=hacker&fdid=org.pocketworkstation.pckeyboard

Python is a great language with an impressive number of tools designed to make developers' life easier. Sometimes, however, the problem is getting to know that these tools exist in the first place. By contributing to projects like OpenStack's Nova client and Falcon, I have recently come across some useful tools that can seriously improve the quality of your code. The first one is called pyflakes, a passive checker of Python programs developed by Phil Frost. What it does is parsing your source files and checking for possible errors such as undefined names and unused imports. Let's consider the following example: <figure class="code"></figure>The code above contains a typo, we have misspelled urllib. Here is what pyflakes thinks about our program:

$ pyflakes example.py
example.py:1: 'urllib' imported but unused
example.py:4: undefined name 'urlib'

On line 4 we try to use urlib which is not defined. Also, we import urllib on line 1 and we do nothing with it. Our typo has been spotted! Notice that, even though our program contains a print statement, 'pyflakes example' has not been printed. That is because pyflakes parses the source files it checks, without importing them, making it safe to use on modules with side effects. pyflakes can be installed with pip or apt-get. The second tool I want to talk about is Ned Batchelder's coverage.py. No doubt you write unit tests for your programs. Right? Good. coverage.py is out there to help you checking how much of your program is actually covered. Let's use as an example codicefiscale, a Python project of mine. First we install coverage:

pip install coverage

Then we run our unit tests:

$ coverage run --source=codicefiscale tests.py
.......
----------------------------------------------------------------------
Ran 7 tests in 0.003s

We pass the module we want to test with --source=codicefiscale so that coverage will only report information about that specific module. Now that our tests have been performed successfully it is time to check how much of our code is covered by unit tests:

$ coverage report -m
Name            Stmts   Miss  Cover   Missing
---------------------------------------------
codicefiscale      73      4    95%   61, 67, 95, 100

Not bad, 95% of our module is covered! Still, coverage let us know that 4 lines have not been touched by the unit tests. With this information, we can go write some meaningful test cases that will also cover the missing lines.

When Sir Tim made a band the first image on the web back in 1992, I do not imagine for a moment he understood the full scope of what was to follow. I also do not imagine Marc Andreessen understood the technical debt he was about to introduce and that fateful day in 1993 when he proposed the img tag allowing inline images.

Many will argue of course that the old adage of my title may not apply to the web, where if it were true, every page view would be like reading a novel! and many of those novels would involve cats or one pixel tall colour gradients.
Leaving aside the philosophical arguments for a moment it takes web browser author a great deal of effort to quickly and efficiently put those cat pictures in front of your eyeballs.
NavigatingImages are navigated by a user in a selection of ways, including:

• Direct navigation to an image like this cat picture is the original way images were viewed i.e not inline and as a separate document not involving any html. Often this is now handled by constructing a generated web page within the browser with the image inline avoiding the need for explicit image content handling.
• An inline img tag (ironically it really does take thousands of words to describe) which puts the image within the web page not requiring the user to navigate away from the document being displayed. These tags are processed as the Document Object Model (DOM) is constructed from the html source. When an img tag is encountered a fetch is scheduled for the object and when complete the DOM completion events happen and the rendered page is updated.
• Imported by a CSS stylesheet.
• inline element created by a script

Whatever the method, the resulting object is subject to the same caching operations as any content object within a browser. These caching and storage operations are not specific to images however images are one of the most resource intensive objects a browser must regularly deal with (though javascript and stylesheet sources are starting to rival it at times) because they are relatively large and numerous.
Pre render processingWhen the image object fetch is completed the browser must process the image for rendering which is where this gets even more complicated. I shall use how this works in NetSurf as I know that browsers internals best, but operation is pretty similar in many browsers.

The content fetch will have performed basic content sniffing to determine the received objects mime type. This is necessary because a great number of servers are misconfigured and a disturbingly large number of images served as png are really jpegs etc. Indeed sometimes you even get files served which are not images!

Upon receipt of enough data to decode the image header, for the detected mime type, the images metadata is extracted. This metadata usually includes things like size and colour depth.

If the img tag in the original source document omitted the width or height of the image the entire document render may have to be reflowed at this point to allow the correct spacing. The reflow process is often unsightly and should be avoided. Additionally at this stage if the image is too large to handle or an unhandled format the object will be replaced with the "broken" image icon.

Often that will be everything that is done with the image, when I added "lazy" image conversion to NetSurf we performed extensive profiling and discovered well over 40% of images on visited pages are simply never viewed by the user but that small (100 pixel on a side) images were almost always displayed.

This odd distribution comes down to how images are used in modern web pages, they broadly fall into two categories of "decoration" and "content" for example all the background gradients and sidebar images etc. are generally small images used as decoration whereas the cat picture above is part of the "content". A user may not scroll down a page to see content but almost always gets to "view" the decoration.
RenderingThe exact browser heuristics used differ as to when the render operation is performed but they all have a similar job to perform. When i say render here this may be possibly as an "off screen" view if they are actually on another tab etc. Regardless the image data must be converted from the source data (a PNG, JPEG etc.) into a format suitable for the browsers display plotting routines.

The browser will create a render bitmap in whatever format the plotting routines require (for example the GTK plotters use a Cairo image surface) , use an image library to unpack the source image data (PNG) into the render bitmap (possibly performing transforms such as scaling and rotation) and then use that bitmap to update the pixels on screen.

The most common transform at render time is that of scaling, this can be problematic as not all image libraries have output scaling capabilities which results in having to decode the entire source image and then scaling from that bitmap.

This is especially egregious if the source image is large (perhaps a multi megabyte jpeg) but the width and height are set to produce a thumbnail. The effect is amplified if the user has set the image cache size limit to a small value like 8 Megabytes (yes some users do this apparently their machines have 32MB of RAM and they browse the web)

In addition the image may well require tiling (for background gradients) and quite complex transforms (including rotation) thanks to CSS 3. Add in that javascript can alter the css style and hence the transform and you can imagine quite how complex the renderers can become.
CachingThe keen reader might spot that repeated renderings of the source image (e.g. because window is scrolled or clipped) result in this computationally expensive operation also being repeated. We solve this by interposing a render image cache between the source data and the render bitmaps.

By keeping the data in the preferred format, image rendering performance can be greatly increased. It should be noted that this cache is completely distinct from the source object cache and relates only to the rendered images.

Originally NetSurf used to perform the render conversion for every image as it was received without exception, rather than at render time, resulting in a great deal of unnecessary processing and memory usage. This was originally done for simplicity and optimising for "decoration" images.

The rules for determining what gets cached and for how long are somewhat involved and the majority of the code within the current implementation NetSurf uses is metrics and statistic generation to produce better decisions.

There comes a time at which this cache is no longer sufficient and rendering performance becomes unacceptable. The NetSurf renderer errs on the side of reducing resource usage (clearing the cache) at the expense of increased render times. Other browsers make different compromises based on the expected resources of the user base.
FinallyHopefully that gives a reasonable overview to the operations a browser performs just to put that cat picture in front of your eyeballs.

And maybe next time your browser is guzzling RAM to plot thousands of images you might have a bit more appreciation to exactly what it is up to.

If you're using the DNSSEC validator and you're reading either my blog or Planet Grep, you may have noticed that the validator icon went from the gray "undefined" version to the green "validated" one. That's right, I have working DNSSEC now with thanks to Philip for doing all the hard work.

Review: Get Everything Done, by Mark Forster

Publisher:	Hodder & Stoughton
Copyright:	2000
ISBN:	0-340-74620-3
Format:	Trade paperback
Pages:	190

Mark Forster is the author of my (current) favorite time management book, Do It Tomorrow, and several excellent blog posts. I've therefore been rather curious about some of his earlier books, and finally decided to order this one. It appears to only have been published in the UK, so it can be a bit expensive in the US unless you can find it used. The main reason why I like Forster's writing so much is that he's a theory and neat trick sort of author instead of a single system author. A lot of time management writing (such as Getting Things Done) presents a single system that's supposedly universal. If that system happens to work for you, great. If it doesn't, the usefulness of the book drops off rapidly. You have to work through the basic principles, which are often sidelined in the book, and come up with variations on your own. Forster is the other sort of time management author: he throws out a flurry of tricks and tactics and lets you see which ones stick. He doesn't have a single system; indeed, one of the most entertaining parts of Get Everything Done is a parable about following many of the common time management systems and having one's life get worse and worse. Instead, he talks about the underlying theory, about the different approaches he's tried and their tradeoffs, and about lots of little tricks that he's found help in one situation or another. It's more of a toolkit than a system. This is, of course, only as good as the clarity of presentation. In both Do It Tomorrow and here, the clarity is excellent. For example, one of the most eye-opening ideas he explores in this book is that time management is a horrible name for the field. Time continues on no matter what you do; you can't increase it, and you can't save it. Rather, what you're actually doing is attention management: for each moment, you're deciding where to direct your attention. Things to which you turn your attention will change; things that you don't pay attention to will not change (except possibly for the worse). I'm quite fond of this reframing of the problem. Forster's thinking about time, or, rather, attention management is not as fully-developed here as in the later Do It Tomorrow. Much of the latter book is about the theory and practice of to-do lists. The techniques presented here were, at least for me, less immediately inspiring, although still thought-provoking. Much of the book focuses on internal resistance and procrastination, on the concept of self-control and decision-making as a mental "muscle" that has to be exercised, and on a philosophy of attention management that slowly builds up to doing whatever one is resisting the most at the moment. I haven't had a chance to work through the exercises that he offers (Forster's books tend to be full of illuminating exercises), so I don't have a fully-formed opinion on their efficacy. I was able to put Do It Tomorrow into practice more immediately. However, one thing this book does do is tackle directly the problem of trying to do too many things. Since this, more than organization, is the heart of my personal attention management problems, I was delighted to see this. Most attention management books at least give lip service to the problem, but they provide little useful guidance. David Allen's Getting Things Done effectively rules it out of scope: the goal of the system is to free you to act on your decisions, but there's little or no attention paid to the practical problem of making those decisions. As a result, I had serious trouble with GTD when I tried to use it. My project and next action lists would simply grow without bound, and GTD offered no useful assistance with culling them. Deciding what to do is, of course, a hard problem, but Forster here offers some specific and useful techniques and spends some time on the necessity of culling one's backlog. He also states directly the problem that everyone else seems to dance around: if you don't cull your committments, no attention management system will actually help you. It will just enable you to do trivia more efficiently, and therefore allow you to fill your life with even more of it, while still feeling just as overwhelmed as before. The bluntness is refreshing, and the exercises in cataloging commitments with time values and then forcing yourself to reduce the commitment list to the doable look quite helpful. I would still start with Do It Tomorrow rather than this book, since I think some practical approaches to to-do list management are one of the best places to start with attention management. But I'm glad I picked up this book as well, despite the cost of the UK import, and I plan on working through the exercises in it. Unlike David Allen, who has one basic system and whose other book was interesting but not as helpful, Forster's toolkit approach means that more books mean more ideas and more possible tools. He doesn't stick with one concept and polish it; he tries a lot of different ideas and then analyzes their strengths and weaknesses. If Do It Tomorrow spoke to you, I recommend grabbing this one as well. (Yes, it's somewhat amusing for me to read and review this book immediately after The Making of the Indebted Man, since to an extent attention management is part of the remaking of the self that's the obligation of the debtor in Lazzarato's construction of the nature of debt. It was something that occurred to me while reading this book. But I think Forster does a good job of showing attention management as a tool to direct one's efforts towards an internal goal rather than externally-imposed goals.) Rating: 8 out of 10

My wife has had a LG Nexus 4 for about 4 months now so it s time for me to review it and compare it to my Samsung Galaxy S3. A Sealed Case The first thing to note about the Nexus 4 is that it doesn t support changing a battery or using micro-SD storage. The advantage of these design choices is that it allows reduced weight and greater strength compared to what the phone might otherwise be. Such choices would also allow the phone to be slightly cheaper which is a massive advantage, it s worth noting that the Nexus 4 is significantly cheaper than any other device I can buy with comparable specs. My wife s phone has 8G of storage (not RAM thanks Robin) and cost $369 at the start of the year while the current price is $349 for the 8G version and $399 for the 16G version. Of course one down-side of this is that if you need 16G of storage then you need to spend an extra $50 on the 16G phone instead of buying a phone with 8G of storage and inserting a 16GB micro-SD card which costs $19 from OfficeWorks. Also there s no option of using a 32G SD card (which costs less than $50) or a 64G SD card. Battery etc The battery on the Nexus 4 isn t nearly big enough, when playing Ingress it lasts about half as long as my Galaxy S3, about 90 minutes to fully discharge. If it was possible to buy a bigger battery from a company like Mugan Power then the lack of battery capacity wouldn t be such a problem. But as it s impossible to buy a bigger battery (unless you are willing to do some soldering) the only option is an external battery. I was unable to find a Nexus 4 case which includes a battery (which is probably because the Nexus 4 is a lot less common than the Galaxy S3) so my wife had to buy an external battery. If you are serious about playing Ingress with a Nexus 4 then you will end up with a battery in your pocket and cable going to your phone from the battery, this is a real annoyance. While being a cheap fast phone with a clear screen makes it well suited to Ingress the issue of having a cable permanently attached is a real down-side. One significant feature of the Nexus 4 is that it supports wireless charging. I have no immediate plans to use that feature and the wireless charger isn t even on sale in Australia. But if the USB connector was to break then I could buy a wireless charger from the US and keep using the phone, while for every other phone I own a broken connector would render the phone entirely useless. Screen Brightness I have problems with my Galaxy S3 not being bright enough at midday when on auto brightness. I have problems with my wife s Nexus 4 being too bright in most situations other than use at midday. Sometimes at night it s painfully bright. The brightness of the display probably contributes to the excessive battery use. I don t know whether all Nexus 4 devices are like this or whether there is some variance. In any case it would be nice if the automatic screen brightness could be tuned so I could make it brighter on my phone and less bright on my wife s. According to AndroSensor my Galaxy S3 thinks that the ambient light in my computer room is 28 lux while my wife s Nexus 4 claims it s 4 lux. So I guess that part of the problem is the accuracy of the light sensors in the phones. On-Screen Buttons I am a big fan of hardware buttons. Hardware buttons work reliably when your fingers are damp and can be used by feel at night. My first Android phone the Sony-Ericsson Xperia X10 had three hardware buttons for settings, home, and back as well as buttons for power, changing volume, and taking a photo which I found very convenient. My Galaxy S3 has hardware buttons for power, home, and volume control. I think that Android phones should have more hardware buttons not less. Unfortunately it seems that Google and the phone manufacturers disagree with me and the trend is towards less buttons. Now the Nexus 4 only has hardware buttons for power, and volume control. One significant advantage of the Galaxy S3 over the Nexus 4 is that the S3 s settings and back buttons while not implemented in hardware are outside the usable screen area. So the 4.8 1280*720 display is all for application data while the buttons for home, settings, and back on the Nexus 4 take up space on the screen so only a subset of the 4.7 1280*768 is usable by applications. While according to specs the Nexus 4 has a screen almost as big as the Galaxy S3 and a slightly higher resolution in practice it has an obviously smaller screen with fewer usable pixels. Also one of the changes related to having the buttons on-screen means that the settings button is often in the top right corner which I find annoying. I didn t like that aspect of the GUI the first time I used a tablet running Android 3.0 and I still don t like it now. GPS My wife s Nexus 4 seems to be much less accurate than my Galaxy S3 for GPS. I don t know how much of this is due to phone design and how much is due to random factors in manufacturing. I presume that a large portion of it is due to random manufacturing issues because other people aren t complaining about it. Maybe she just got unlucky with an inaccurate phone. Shape and Appearance One feature that I really like in the Samsung Galaxy S is that it has a significant ridge surrounding the screen. If you place a Galaxy S face-down on a desk that makes it a lot less likely to get a scratch on the screen. The LG U990 Viewty also had a similar ridge. Of course the gel case I have bought for every Android phone has solved this problem, but it would really be nice to have a phone that I consider usable without needing to buy such a case. The Nexus 4 has a screen that curves at the edges which if anything makes the problem worse than merely lacking a ridge around the edge. On the up-side the Nexus 4 looks and feels nice before you use it. The back of the Nexus 4 sparkles, that s nice but when you buy a gel case (which doesn t seem to be optional with modern design trends) you don t get to see it. The Nexus 4 is a very attractive package, it s really a pity that they didn t design it to be usable without a gel case. Conclusion Kogan is currently selling the Galaxy S3 with 16G of storage for $429. When comparing that to the 16G version of the Nexus 4 at $399 that means there s a price of $30 to get a SD socket, the option of replacing a battery, one more hardware button, and more screen space. So when comparing the Google offers for the Nexus 4 with the Kogan offer on the Galaxy S3 or the Galaxy Note which also has 16G of storage and sells for $429 the Google offer doesn t seem appealing to me. The Nexus 4 is still a good phone and is working well for my wife, but she doesn t need as much storage as I do. Also when she got her phone the Galaxy S3 was much more expensive than it is now. Also Kogan offer the 16G version of the Nexus 4 for $389 which makes it more appealing when compared to the Galaxy S3. It s surprising that they can beat Google on price. Generally I recommend the Nexus 4 without hesitation to anyone who wants a very capable phone for less than $400 and doesn t need a lot of storage. If you need more storage then the Galaxy S3 is more appealing. Also if you need to use a phone a lot then a Galaxy S3 with a power case works well in situations where the Nexus 4 performs poorly.

A week ago, we started the Debian systemd survey. The goal was to figure out a few trends and answer the following two questions:

1. Do our subjective impressions from the discussions on debian-devel reflect the general sentiment about systemd?
2. What are the main concerns that most people have?

Thank you all for your participation! General I am happy to tell that 2113 people had a look at the survey and 573 people actually participated. Of those, 45.7% said they are a DD, DM or otherwise maintaining packages. 74.5% said they actually booted and used a computer running systemd. With regards to having systemd in Debian at all, not necessarily as the default init system, answers are as follows:

• 62.4% voted I welcome systemd in Debian, everything is fine
• 14.1% are not sure yet.
• 8.0% don t care.
• 15.3% don t want systemd in Debian.

43.9% said they personally want systemd as the default init system in Debian, while 32.2% don t want that. The remaining 23.7% don t know yet. Top concerns About 50% of participants provided one or more concerns. Evaluating this part of the survey is obviously the hardest, since the answers were provided as free text. I tried categorizing the feedback into a few buckets. Each bucket comes with a number which is a weighted (!) count, i.e. the top concern counts 3 times, the second concern counts 2 times and the last concern just once. If you cannot find your personal concerns, that is because those which were just voiced by less then five people are not listed here. As I said, we cared about trends in this survey, not individual opinions.

1. systemd is too complex, or bloated, or it does too many things, or has too many dependencies (weight: 217)
2. systemd is not portable to non-linux systems, e.g. Debian/kFreeBSD or HURD (weight: 199)
3. Debugging the boot process is harder than in sysvinit (weight: 106)
4. I have a problem with systemd upstream and/or Lennart in particular (weight: 87)
5. systemd violates the UNIX philosophy (weight: 35)
6. I dislike binary logs and/or the journal in general (weight: 30)
7. systemd is too new, still untested, unstable and experimental (weight: 24)
8. I cannot find enough documentation in general or about the transition from sysvinit to systemd in particular (weight: 20)
9. People need to learn new commands/how the new system works (weight: 20)
10. I don t know what problems systemd solves and/or have no problems with sysvinit currently (weight: 19)
11. I think the configuration is binary and/or the configuration format is weird (weight: 13)
12. systemd s code is not good (memory leaks, performance problems) and/or upstream s development lacks best practices such as long-term stable branches (weight: 9)
13. There are problems with systemd in Debian (e.g. Debian-specific extensions to /etc/fstab not supported, system doesn t boot) (weight: 9)
14. Customizing the boot is harder than with sysvinit (weight: 8)
15. systemd is not compatible with sysvinit (weight: 8)

I realize that the choice of buckets is somewhat broad and there are many different, finely nuanced opinions out there. Again, this is for seeing a trend, not accounting for every single individual opinion. In case you strongly believe that I did something wrong when evaluating the survey results, please contact me and we can work something out. Conclusions/Actions I know this is a controversial topic. Please don t start yet another systemd discussion on debian-devel. We, the systemd Debian maintainers, will try to come up with good answers to all listed concerns and communicate them in a friendly and concise way soon. Furthermore, we have recognized the need for more documentation/information about how things are supposed to work with regards to the transition (and systemd in general) and will address that, too. Raw questions/numbers

Total records in survey: 573
Are you a Debian Developer (DD) or Debian Maintainer (DM) or otherwise currently maintaining Debian packages?
262 Yes
311 No
Did you ever boot and use a computer running systemd? It does not matter whether that computer was running Debian or a different operating system.
427 Yes
146 No
What is your general sentiment towards having systemd in Debian (not necessarily as default)?
358 I welcome systemd in Debian, everything is fine.
 81 I am not sure yet.
 46 I don t care.
 88 I don t want systemd in Debian.
Would you personally want systemd as the default init system in Debian?
252 Yes
136 I don t know
185 No

Two days ago, I asked how I could install Linux on a Packard Bell EasyNote LV computer preinstalled with Windows 8. I found a solution, but am horrified with the obstacles put in the way of Linux users on a laptop with UEFI and Windows 8. I never found out if the cause of my problems were the use of UEFI secure booting or fast boot. I suspect fast boot was the problem, causing the firmware to boot directly from HD without considering any key presses and alternative devices, but do not know UEFI settings enough to tell. There is no way to install Linux on the machine in question without opening the box and disconnecting the hard drive! This is as far as I can tell, the only way to get access to the firmware setup menu without accepting the Windows 8 license agreement. I am told (and found description on how to) that it is possible to configure the firmware setup once booted into Windows 8. But as I believe the terms of that agreement are completely unacceptable, accepting the license was never an alternative. I do not enter agreements I do not intend to follow. I feared I had to return the laptops and ask for a refund, and waste many hours on this, but luckily there was a way to get it to work. But I would not recommend it to anyone planning to run Linux on it, and I have become sceptical to Windows 8 certified laptops. Is this the way Linux will be forced out of the market place, by making it close to impossible for "normal" users to install Linux without accepting the Microsoft Windows license terms? Or at least not without risking to loose the warranty? I've updated the Linux Laptop wiki page for Packard Bell EasyNote LV, to ensure the next person do not have to struggle as much as I did to get Linux into the machine. Thanks to Bob Rosbag, Florian Weimer, Philipp Kern, Ben Hutching, Michael Tokarev and others for feedback and ideas.

About 10 years ago I started using an electric shaver. An electric shaver is more convenient to use as it doesn t require any soap, foam, or water. It is also almost impossible to cut yourself properly with an electric shaver which is a major benefit for anyone who s not particularly alert in the morning. Generally my experience of electric shavers has been good, although the noise is quite annoying. Recently a friend told me that an electric shaver is as noisy as a chain-saw. Given the inverse-square law and the fact that the shaver operates within 1cm of my ears that sounds plausible. So the risk of hearing loss is a great concern. Disposable ear plugs are very cheap and they can be used multiple times (they don t get particularly dirty while shaving or get squashed in the short time needed to shave). So for a few weeks I ve been using ear plugs while shaving which reduces the noise and presumable saves me from some hearing damage although after 10 years of using electric shavers I may have already sustained some damage. According to Cooper Safety their ear plugs reduce noise by 29dB, [1] I presume that the cheap ones I bought from Bunnings would be good for at least 15dB. According to Better Hearing Sydney the noise from an electric shaver is typically around 90dB, less than the 100dB that is typical of a chain-saw [2]. So if my ear-plugs are good for 15dB then they would reduce the noise from a typical electric shaver to 75dB which is well below the 85dB that will cause hearing damage. Given that the noise from a typical shaver is only slightly above the damage threshold it seems that I might not need particularly good ear-plugs when shaving. A quick scan of shaver reviews indicates that the amount of noise differs by brand and technology. The Hubpages review suggests that rotary shavers tend to make less noise than foil shavers [3], but I m sure that it varies enough between brands that some rotary shavers are louder than the quietest foil shavers. It seems that the best thing to do when buying a new shaver would be to go to a specialised shaver shop (which has many models on offer) and get the staff to demonstrate them to determine which is the quietest. If a typical shaver produces 90dB then it seems likely that one of the more quiet models would produce less than 85dB. Another item on my todo list is to buy a noise meter to measure the amount of noise produced in the places where I spend time. There are some Android apps to measure noise, I m currently playing with the Smart Tools Co Sound Meter [4] which gives some interesting information. The documentation notes that phone microphones are limited to the typical volume and frequencies of human voice, so my Galaxy S3 can t measure anything about 81dB. My wife s Nexus 4 doesn t seem to register anything above 74dB. Additionally there is some uncertainty about the accuracy of the microphone, there is a calibration feature but that requires another meter. Anyway the Sound Meter app suggests that my shaver (a Philips HQ7380/B) produces only 71dB at the closest possible range and drops down to 67dB at the range I would use if I grew sideburns. Conclusion Getting a proper noise meter to protect one s hearing seems like a good idea. An Android app for measuring noise is a good thing to have, even though it s not going to be accurate it s convenient and will give an indication. When buying a shaver one should listen to all the options and choose a quiet one (I might have got a quiet one by luck). Sideburns seem like a good idea if you value your hearing.

• [1] http://www.coopersafety.com/NoiseReduction.aspx
• [2] http://www.betterhearingsydney.org.au/content/view/46/53/
• [3] http://tinyurl.com/ojxfx9t
• [4] https://play.google.com/store/apps/details?id=kr.sira.sound

Review: The System of the World, by Neal Stephenson

Series:	The Baroque Cycle #3
Publisher:	William Morrow
Copyright:	2004
ISBN:	0-06-052387-5
Format:	Hardcover
Pages:	892

This is the third book of the three-volume Baroque Cycle. I think you could, if you really wanted, read it without reading the previous volumes; Stephenson is certainly long-winded enough that you can pick up most of what's going on while you read. It's been a year since I read the second volume, and I only resorted to Wikipedia a couple of times to remember plot elements (and mostly from the first book). However, I wouldn't recommended starting here. Many of the character relationships, and most of the underpinning of the plot, is established in the previous volumes and given more significance by them. You would also miss The Confusion, which is the best book of the series, although none of this series rises to the level at which I'd recommend it except under specific circumstances. Quicksilver establishes the characters of Daniel Waterhouse, a fictional Puritan whose family was close to Cromwell and who became a friend to Isaac Newton in the days following the Restoration; Jack Shaftoe, a vagabond who wanders Europe in a sequence of improbable adventures; and Eliza, who becomes a friend to Leibniz and a spy for William of Orange. The Waterhouse sections are prominent in Quicksilver: full of the early history of the Royal Society, alchemy, and a small amount of politics. Of those three characters, Eliza is by far the most interesting, which meant that I was delighted when The Confusion dropped Waterhouse almost entirely and mixed Eliza's further story with more improbable but entertaining sea adventures of Jack Shaftoe. You will immediately sense my root problem with The System of the World when you hear that it is almost entirely about Daniel Waterhouse. While Eliza and Jack both appear, they play supporting roles at best, and Eliza's wonderful sharp intelligence and pragmatic survival skills are left out almost entirely. Instead, this is a novel about Waterhouse's return to England after spending quite a bit of time in the American colonies working on calculating machines. He is almost immediately entangled in dangerous politics from multiple directions: the precarious national politics in England near the end of the reign of Queen Anne, Isaac Newton's attempts to maintain the currency of England as Master of the Mint, and a bombing attempt that may have been aimed at him, may have been aimed at Newton, and may have been aimed at someone else entirely. Much of the book consists of an extended investigation of this bombing plot, skullduggery involving counterfeiters, and attempts to use the currency and the Mint as part of the political conflict between Whigs and Tories, mixed in with attempts to construct a very early computer (this is Stephenson, after all). Leibniz and Eliza come into this only as confidants of the Hanoverians. All this may sound exciting, and there are parts of it that hold the attention. But this book sprawls as badly as Quicksilver did. There's just too much detail without either enough plot or enough clarity. Stephenson tries to make you feel, smell, and hear the streets of London and the concerns of an idiosyncratic group of semi-nobles during one of the more interesting junctures of British history, but he does that by nearly drowning you in it, and without providing enough high-level guidance. For most of the book, I felt like I was being given a tour of a house on my hands and knees with a magnifying glass. It's a bad sign when the reader of a historical novel is regularly resorting to Wikipedia, not to follow interesting tangents of supporting material, but to try to get a basic sense of the players and the politics involved because the author never explains them clearly. If you're more familiar with the details of British history than I am, and can more easily follow the casual intermixing of two or three forms of address for the same historical figure, you may not have that problem. But I think other structural issues remain, and one of the largest is Waterhouse himself. Jack Shaftoe, and particularly Eliza, are more interesting characters because they're characters. They're not always particularly believable, but they attack the world with panache and are constantly squirming into the center of things. Stephenson's portrayals of Newton, Leibniz, the Duke of Marlborough, Sophia of Hanover, Peter the Great, and the other historical figures who show up here are interesting for different reasons: Stephenson has history to draw on and elaborate, and it's fascinating to meet those people from a different angle than dry lists of accomplishments. History has a way of providing random details that are too bizarre to make up; Isaac Newton, for example, actually did disguise himself to infiltrate London criminal society in pursuit of counterfeiters while he was Master of the Mint! Waterhouse, for me, has none of these advantages. He is an invented character in whom I have no pre-existing interest. He drifts through events largely through personal connections, all of which seem to be almost accidental. He's welcome in the councils of the Royal Society because he's apparently a scientist, but the amount of actual science we see him doing is quite limited. His nonconformist background allies him squarely with the Whigs, but his actual position on religious matters seems much less set than the others around him. What he seems to want, more than anything else, is to help Leibniz in the development of a computer and to reconcile Newton and Leibniz. And he's not particularly effective at either. In short, he has little in the way of memorable character or dynamism, despite being the primary viewpoint character, and seems to exist mostly to know everyone and be everywhere that's important to the story. He feels like an authorial insertion more than a character. It's quite easy to believe that Stephenson himself would have loved to be in exactly the role and situation that Waterhouse finds himself in throughout the book, in the middle of the councils of the wise and powerful, in just the right position to watch the events of history. I can sympathize, but it doesn't make for engrossing reading. Novels live and die by the strength of their characters, particularly their protagonists; I want more than just a neutral viewpoint. The third major structural problem that I had with this book is that I think Stephenson buries his lede. After finishing it, I think this is a book with a point, a central premise around which all the events of the story turn, and which is the philosophical culmination of The Baroque Cycle as a whole. But Stephenson seems oddly unwilling to state that premise outright until the very end of the book. For the first half, one could be forgiven in thinking this is a story about alchemy and the oddly heavy gold that's been a part of the story since The Confusion, or perhaps about foundational but forgotten work on computation that preceded Babbage by a century. But those all turn out to be side stories, sometimes even without a proper conclusion. I appreciate honoring the intelligence of the reader, and I presume that Stephenson would like to guide the reader through the same process of realization that the characters go through, but I think he takes this much too far and fails to make the realization clear. I'll therefore state what I believe is the premise outright, since I think it's a stronger book with this idea in mind: The System of the World is a continuation of the transformational economics shown in The Confusion into the realm of politics. Specifically, it's about the replacement of people with systems, about the journey towards Parliamentary supremacy, central banking, and the persistent state, and about the application of scientific principles of consistency and reproducibility to politics and economics (however fitfully and arbitrarily). Quicksilver was about the rise of science; The Confusion was, in retrospect, about the rise of economics; and The System of the World tries to be about the rise of technocratic modern politics, barely perceptible among the squabbles between Tories and Whigs. I think that's a fascinating premise, and I would have loved to read a book that tackles it head-on. That's a concept that is much more familiar from the late 19th and early 20th centuries in the context of Marxism, early socialism, technological utopianism, and similar attempted applications of scientific analysis to political and human behavior for the betterment of human civilization. Shifting that 200 years earlier and looking at a similar question from the perspective of the giants of the Enlightenment feels full of of potential. There are moments when I think Stephenson captures the sense of a seismic shift in how economies are run, knowledge is established, and civilizations are knit together. But, most of the time, it just isn't clear. There's so much other stuff in this book, and in the whole series: so many false starts, digressions, abandoned plots, discarded characters, and awkward attempts at romance (as much as I like the characters, Stephenson's portrayal of the relationship between Eliza and Jack is simply ridiculous and not particularly funny) that the whole weight of the edifice crushes what I think is the core concept. Stephenson is never going to be sparse. When you start a Stephenson novel, you know it's going to be full of chunks of partly digested encyclopedia and random research findings that may have nothing to do with the plot. But his best books (Snow Crash, The Diamond Age, even Cryptonomicon) have an underlying structure off of which all of those digressions are hung. You can see the bones beneath the flesh, and the creature they create is one you want to get to know. I'm not sure there are any bones here, and that may be the peril, for Stephenson, of writing historical fiction. I wonder if he felt that the structure of history would provide enough structure by itself that he could wrap a few plots around the outside of it and call it good. If so, it didn't work, at least for me. A lot of things happen. Some of them are even exciting and tense. A lot of people meet, interact, and show off their views of the world. A great deal of history, research, and sense of place is described in painstaking detail. But at the end of the book, I felt like I had to reach for some sort of point and try to retrofit it to the story. Lots happened, but there wasn't a novel. And that makes it quite hard to get enthused by the book. If you adored Quicksilver, I suspect you will also like this. I think they're the most similar. If, like I did, you thought The Confusion was a significant step up in enjoyment in the series and were hoping the trend will continue, I'm sad to report that it didn't. If you were considering whether to read the whole series and were waiting to see what I thought of the end, my advice is to give The Baroque Cycle a pass unless you absolutely love Stephenson's digressions, don't care if they're about history instead of current technology, and cannot live without 3,000 pages of them. It's not that they're bad books, but they're very long books, they take a significant investment of time and attention, and I think that, for most readers, there are other books that would repay a similar investment with more enjoyment. Rating: 5 out of 10

One of the things I do with computers is "do stuff with music". I'm not a professional musician by any means, but I do sometimes have a need for some software to do some music editing. In the past, that meant using GNU LilyPond; and while that's certainly an interesting piece of software, it has some idiosyncracies that have made me dislike it in the past. So when I learned about PMW, written by Philip Hazel (of PCRE and Exim fame) I was intrigued. PMW has several advantages over lilypond, in my opinion. To name but two: its syntax is less silly, and it takes far less time to convert something from source to graphic, to the extent that I've considered creating an editor which would update the result after every keystroke, something that just isn't possible with lilypond. The decision to upload pmw into Debian was just a no-brainer, and it's saved me some time since, already. Enjoy!

Ben Goldacre (Bad Science), is running a campaign for all medical trials to be published. It seems that best current evidence indicates that about half of the trials for treatments currently in use remain unpublished. That's pretty astounding when you think about it. Given that many of the trials that are published only compare new treatments against placebo, rather than against the best available existing treatment, and often barely show them as being more effective than homeopathy^Wsugar, one has to wonder how dire were the results that are not being published. If you prefer to have science done in the open, then I'd encourage you to visit www.alltrials.net and sign the petition and/or give them a donation. The fix is pretty straight-forward: Simply insist that clinical trials have to register before they start in order to be considered valid, and that all registered trials have to report their results. It need not be expensive to do -- a git repo. shared across the industry, containing a file for each trial in a standard format would do the trick probably. I imagine they'll come up with a more expensive solution, but in comparison to the cost of running a decent sized trial, it'll still be pocket change. (A note from the campaign, sent to existing petition signatories, is what prompted this blog post -- please read it and be inspired to help)

On Monday, I was a visitor and guest speaker in a session on Open Learning in a class on Learning Creative Learning which aims to offer a course for designers, technologists, and educators. The class is being offered publicly by the combination surprising but very close to my heart of Peer 2 Peer University and the MIT Media Lab. The hour-long session was facilitated by Philipp Schmidt and was mostly structured around a conversation with Audrey Watters and myself. The rest of the course materials and other video lectures are on the course website. You can watch the video on YouTube or below. I thought it was a thought-provoking conversation! <iframe allowfullscreen="" frameborder="0" height="315" src="http://www.youtube.com/embed/l9HM80cv160" width="560"></iframe> If you re interested in alternative approaches to learning and free software philosophy, I would also urge you to check out an essay I wrote in 2002: The Geek Shall Inherit the Earth: My Story of Unlearning. Keep in mind that the essay is probably the most personal thing I have ever published and I wrote it more than a decade ago it as a twenty-one year old undergraduate at Hampshire College. Although I ve grown and learned enormously in the last ten years, and although I would not write the same document today, I am still proud of it.

As most people that are using that funny grey on black thing with the blinking white box AKA a commandline, I do have a heavily configured shell. zsh in my case. Some while ago my old configuration for it started to annoy me and so I set out to redo it. With the basic requirement to be flexible and able to adjust to various zsh versions (back as far as Lenny). I ve set out and looked how others do it and took the (I hope) best bits and put them together in a way I like it. Maybe others want to pick from me, so here I describe a little, maybe someone is interested First - the config is completly inside .zsh. The only thing directly in my $HOME is a symlink from $HOME/.zshenv to $HOME/.zsh/zshenv.home. All in one place, nicer this way. The zshenv just sets ZDOTDIR, so zsh then uses the .zsh itself. Next I am using modules . Well, actually everything is splitted out in small(er) files, so its way easier to maintain. And to overwrite stuff wherever I need to. So my .zshrc just loads those module files - and then goes and checks if it finds the same file inside a series of subdirectories. Those subdirectories are based on the hostname, the kernel name, the username, the domain name and the name of the distribution of the system. And a number of combinations of those. That system allows me, for example, to have a set of aliases defined only on Debian systems (like those to do with apt-get & co). Or define some extra variables if I login to the host franck, domain debian.org. Or whatever more. I m also on the way of doing something similar for all my dotfiles. While I was working at that I finally got fed up with the fact that my prompt, which is based on Phil! s wasn t doing what I wanted it on various of the hosts I access. Thankfully someone pointed me at a change to the grml zsh config: Frank Terbeck rewrote their prompt to make use of the zstyle system. Now that got me going, I like the idea of having the whole prompt easily configurable and changeable. My prompt always has shown slight differences depending on where the shell runs, which meant I had to carefully craft PS1 for every such change, and when one changes something one had to check all the places to adjust them too. No longer. I took Franks work and extended it for me. I wanted to still have a design matching my old prompt (minus colors, I changed color themes anyways), but with full flexibility the zstyle system can offer here. Now I am at a point where

• One zstyle call can change the information or order in my prompt.
• The prompt automagically leaves out information when the terminal width gets under a limit,
• I can have whatever extra information items in the prompt, even if the prompt never defined a default for it. Including running neccessary functions to update those extra items.
• the prompt switches between color and black/white mode with one zstyle change,
• the prompt draws lines differently, depending on the capabilities of the terminal.

As an example, on the ftp-master host my prompt, while otherwise being the same as everywhere else, contains one extra item - displaying the current status of the archive (dinstall). If you want to try it, the setup file is available, but note that I don t give any warranty. :) Works for me . I load it in my Prompts module, while having the prompt setup file in my function path. The 4 commented lines, my testcase, are a nice example of a custom token, though a real life one, the setup for the ftp-master prompt with the one extra item can be found over here. Comments? Bugfixes? Enhancements? Update: Got asked for an example how to use my prompt to fake another. So here is what you need to do to use my prompt setup to imitate the prompt clint, as delivered with zsh:

autoload promptinit && promptinit
zstyle ':prompt:ganneff' vcs_info true
# Alternatively you can set whatever you like it to be.
zstyle ':prompt:ganneff' set_vcs_info_defaults true
zstyle ':prompt:ganneff' colors true
## no right prompt
zstyle ':prompt:ganneff:right:setup' use-rprompt false
## color of brackets depending on variable
zstyle ':prompt:ganneff:*:items:openbracket' pre '$ $ SSH_CLIENT+"$ PR_YELLOW " :-"$ PR_RED " '
zstyle ':prompt:ganneff:*:items:openbracket' post '$ PR_NO_COLOR '
zstyle ':prompt:ganneff:*:items:closebracket' pre '$ $ SSH_CLIENT+"$ PR_YELLOW " :-"$ PR_RED " '
zstyle ':prompt:ganneff:*:items:closebracket' post '$ PR_NO_COLOR '
zstyle ':prompt:ganneff:*:items:openanglebracket' pre '$ $ SSH_CLIENT+"$ PR_YELLOW " :-"$ PR_RED " '
zstyle ':prompt:ganneff:*:items:openanglebracket' post '$ PR_NO_COLOR '
zstyle ':prompt:ganneff:*:items:closeanglebracket' pre '$ $ SSH_CLIENT+"$ PR_YELLOW " :-"$ PR_RED " '
zstyle ':prompt:ganneff:*:items:closeanglebracket' post '$ PR_NO_COLOR '
## extra date format, and its color
zstyle ':prompt:ganneff:*:items:date' token '%D %a %y/%m/%d %R %Z '
zstyle ':prompt:ganneff:*:items:date' pre '$ PR_CYAN '
## pts. %l instead of %y, also color again
zstyle ':prompt:ganneff:*:items:pts' token '%l'
zstyle ':prompt:ganneff:*:items:pts' pre '$ PR_GREEN '
zstyle ':prompt:ganneff:*:items:pts' post '$ PR_NO_COLOR '
## host ends with :
zstyle ':prompt:ganneff:*:items:host' token '%m:'
## and a different style for the rc level
zstyle ':prompt:ganneff:*:items:rc' token '%(?..[%?%1v] )'
zstyle ':prompt:ganneff:*:items:rc' pre ''
## change color for other parts that differ to my default
zstyle ':prompt:ganneff:*:items:user' pre '$ PR_GREEN '
zstyle ':prompt:ganneff:*:items:host' pre '$ PR_GREEN '
zstyle ':prompt:ganneff:*:items:at' pre '$ PR_GREEN '
zstyle ':prompt:ganneff:*:items:path' pre '$ PR_GREEN '
zstyle ':prompt:ganneff:*:items:history' pre ''
## Show the shell level in a different way
zstyle ':prompt:ganneff:*:items:shell-level' pre ''
zstyle ':prompt:ganneff:*:items:shell-level' token 'zsh%(2L./$SHLVL.) '
## And history is just a bold number. Lazy here, not using pre and post
zstyle ':prompt:ganneff:*:items:history' token '%B%h%b '
## And the last part in prompt, a # or % depending on privileges
## Using standard zsh tokens for bold
zstyle ':prompt:ganneff:*:items:privileges' pre '%B'
zstyle ':prompt:ganneff:*:items:privileges' post '%b'
## Now there are two parts not defined by default, so lets create them
## Both are simple existing variables, no need for extra precmd functions
## system info
zstyle ':prompt:ganneff:extra:ostype' pre '$ PR_CYAN '
zstyle ':prompt:ganneff:extra:ostype' post '$ PR_NO_COLOR '
zstyle ':prompt:ganneff:extra:ostype' token "$ MACHTYPE /$ OSTYPE /$(uname -r)"
## zsh version
zstyle ':prompt:ganneff:extra:zshvers' pre '$ PR_CYAN '
zstyle ':prompt:ganneff:extra:zshvers' post '$ PR_NO_COLOR '
zstyle ':prompt:ganneff:extra:zshvers' token "$ ZSH_VERSION "
zstyle ':prompt:ganneff:left:full:setup' items \
    openbracket date closebracket openbracket pts closebracket openbracket ostype closebracket \
    openbracket zshvers closebracket newline openanglebracket user at host \
    path closeanglebracket newline \
    shell-level space history rc space vcs privileges space
prompt ganneff

And if you now tell me Uh, thats so much more than just saying /prompt clint/ , then you are right. But then: This way is flexible. As I wrote above, my prompt on the ftpmaster host is different. Actually, my prompt on all machines inside the domain debian.org differs, by having

zstyle ':prompt:ganneff:*:items:host' pre '$ PR_YELLOW '

in the Prompts definition for domain:debian.org. And thats enough to show me im on a .debian.org machine by a yellow hostname, instead of my default red. On the ftpmaster host I have the additional few lines: # Want one more piece in my prompt here, dinstall status zstyle :prompt:ganneff:left:full:setup items \ ulcorner line openparentheses user at host pts closeparentheses line history \ line dinstall line shell-level line flexline openparentheses path closeparentheses line urcorner newline \ llcorner line rc openparentheses time closeparentheses line vcs line change-root pipe space

zstyle ':prompt:ganneff:extra:dinstall' pre '$ PR_CYAN '
zstyle ':prompt:ganneff:extra:dinstall' post '$ PR_NO_COLOR '
zstyle ':prompt:ganneff:extra:dinstall' token '$DINSTALL'
zstyle ':prompt:ganneff:extra:dinstall' precmd jj_update_dinstall
zmodload zsh/mapfile
jj_update_dinstall ()  
    DINSTALL="$ $ (z)$ (f)mapfile[/srv/ftp.debian.org/web/dinstall.status] [2] [3,99] "
 

And woo, thats simple. I think. (There ought to be a way to just easily add the item at a defined place in the items zstyle, but meh, too lazy to look).

I love programming. I was born to code. I want to save the world by writing code. I feel very strongly about software freedom. As I get older, and my eyes open to see more of the evil in the world, I become more concerned about freedom in general. Software freedom is, at least traditionally, about permission use, study, modify, and re-distribute software. The Free Software Foundation expresses this as the four essential freedoms. Debian expanded on that, and produced the Debian Free Software Guidelines. This is no longer enough. It is not enough to have all the freedom when you using your own computer, to have the source code to every bit of code that runs on your hardware. We live in the era of the Internet. Much of what we use computers for involves communication over the Internet, and the Internet is being actively used to curtail the freedom of people. For example, governments and corporations do large-scale surveillance of everyone, by eavesdropping on private communications, gathering enormous databases of personal data, and by analysing everything they can in order to find patterns and make conclusions both at the statistical level and about individuals. This ruins privacy. Without privacy, democracy cannot survive. Another example: in the name of various strawmen, such as terrorism, copyright violations, drugs, and child pornography, governments and corporations are collaborating in limiting private people's communications. I'm a Finnish citizen living in the UK. Both countries are among the closest ones to an ideal democractic nation state. Both countries arbitrarily block access to websites based on lists provided by private organisations, assuming that those organisations produce accurate lists of sites that contain copyright violations. As a result, both countries blocked, for example, a site where musical artists promoted their own works, bypassing the large media corporations that fund the list-making organisation. These issues transcend software freedom, though they interact with it. Software freedom is a necessary requirement for freedom, in a world where almost everything is done with, or controlled by, the use of computers. Software freedom is not enough to prevent censorship or surveillance: even if all the software in the world were free, including the national firewalls of China, Finland, and the UK, this would not prevent those countries from censoring and surveilling their citizens. The firewall would run free software, but that does not give the citizens the freedom to disable, or modify, the firewall systems. Fixing these issues is not a coding task. It is a job for politics, and it is going to take a long time, I fear. In the mean time, is there something a hacker can do to improve things? My main hobby project is Obnam, my backup program. Does that help people to protect their freedom? I think it does, in a small way: Obnam supports online, encrypted backups (and de-duplication even for encryption is used), which means they can make backups to servers anywhere on the Internet without having to fear their data gets read and analysed by hostile entities such as their own government, other governments, large corporations, or criminals. Obviously this does not help them if their government prohibits the use of encryption, or requires key escrow, or mandates backdoors to all encryption methods. But it's a step in the right direction. I don't claim Obnam will save the world, but a million small such steps by a thousand individual hackers, even without any particular organisation or guidance, will make a big impact. What step can you take?

Due to the data loss I blogged about, I had to reverse engineer the encryption used by git-annex for its encrypted special remotes. The file system on which the content lived has a bullet hole of 8 GB in it, which was helpfully discarded by pvmove. It's pretty unhappy about that fact, parts of the git repository are unusable and directories cannot be accessed anymore. git-annex cannot possibly run anymore.

However, I was still able to access the git-annex branch within said git repository (using porcelain). This branch contains a file called remote.log which contains the keys of the special remotes. There's one per remote, encrypted to a GPG key of your choice and all files within that remote are encrypted with the same symmetric key.

One small detail stopped me from getting the decryption right the first time, though. It seems that git-annex uses randomness generated by GPG and armored into base64. In my na vet I spotted the base64 and decoded it. Instead it's used verbatim: the first 256 bytes as HMAC key (which reduces randomness to 192 bytes) and the remaining bytes for the symmetric key used by GPG (which will do another key derivation for CAST5 with it). A bug about that just hit the git-annex wiki.

With that knowledge in mind I wrote a little tool that's able to generate encrypted content keys from the plain ones used in the symlinks. That helps you to locate the file in the encrypted remote. Fetch it and then use the tool to decrypt the file in question with the right key.

The lesson: Really backup the git repository used with git-annex and especially remote.log. I'm now missing most of the metadata but for some more important files it's luckily still present. Recovery of the file content does not depend on it if you can deduce the filename from the content. If you have many little files it might be a bit futile without it, though.

If you use LVM with Wheezy on a solid-state drive, you really want to install the latest lvm2 update (i.e. 2.02.95-6, which contains the changes of -5). Otherwise, if you set issue_discards=1 in /etc/lvm/lvm.conf, you will experience severe data loss when using pvmove. Happened to me twice, once I didn't care (chroot data being lost), the second time (today) I did. Not fun, especially when the backup of the data was scheduled for the same day.

One has to wonder why it takes three months for a bug that trashes data to reach testing. (Obviously I know the answer, but they're not particularly good reasons.) Other distributions, like Ubuntu, were much quicker to notice and incorporate that fix. And in the case of the named distribution not because they auto-synced it from unstable. If somebody notices such a grave bug, please yell at people to get the fix out there to our users. Thanks.

Server management on daily basis in a growing environment could be a challenge. Most of the tasks is here done with ClusterSSH in help with a homebrew mail notification. Unfortunately this workflow is not scaling well for 200+ systems. I had a look into apt-dater but this seems not to fit our workflow. FAI looks a bit overengineered at the first glance. Maybe Puppet is an option? There seems to be many extensions for it, unfortunately ruby is needed on every single node. Is there a CTO-compatible overview about puppet, any other alternatives? ;) Update: Many thanks for the hints from Andr Lu s Lopes, Stig Sandbeck Mathisen, Phil Miller, Steve Kemp, Andrew Latham, Bob Proulx and Natxo Asenjo

• Chef
  • Packaged in Debian
  • Upstream Debian packages (no recent one)
• CFEngine3
  • No ruby/perl/python dependencies
  • Light, fast
  • (A bit) harder to understand
  • Packaged in Debian
  • Upstream Debian packages
• Salt
  • Very young
  • Packaged in Debian
• Ansible
  • Very flexible
  • Easy to understand
  • Relies on ssh
  • Open ITP
  • PPA
• MCollective
  • Framework for building server orchestration and parallel job execution
  • Could extend for example Puppet or Chef
  • Packaged in Debian
  • Upstream Debian packages (no recent one)
• Foreman
  • Puppet dashboard and node classifier
  • Open ITP
  • Upstream Debian packages

Old but conceptual still valid: www.infrastructures.org, for example Bootstrapping an Infrastructure Other thoughts: push- or pull-infrastructure? Software footprint (on nodes and your central instance)! Hints, rants and comments could be send to 'blog - at - waja - dot - info' or via @blogwajainfo.

Well this is just an introductory post to set of posts I'm going to write down here on my blog. Idea is to improve the documentation of CDBS but I still don't have any idea on how I can patch the existing documentation, but in the mean time I'm learning new tricks from Jonas which I want to document some where so I thought my blog would be a good place as whole blog is in markdown format and its the same format me and Jonas agreed to convert the existing CDBS documentation. So this blog will act as a documentation and these post will be then altered modified and put back into a proper CDBS documentation later. I know many people don't like CDBS and most of it because there is no proper documentation, so I'm trying to improve the situation so sit back and enjoy the upcoming posts :-). OK I was sloppy in giving theory on what others think about the CDBS thanks to Phill Hands and Jonas for enlightening me. So with these series I'm just trying to explain CDBS features with real examples and examples how you can tame nasty packaging beasts with CDBS easily.