Search Results: "nma"

20 September 2011

Kai Wasserb ch: TNEF or how to lock-up your e-mails

As the administrator for several MTAs I've received my fair share of support requests for "unreadable" e-mails. They generally have an attachment called winmail.dat. This is what all (for exceptions see the rest of this blog post) non-Outlook MUAs can display, when they receive an e-mail with the application/ms-tnef (or application/vnd.ms-tnef) MIME type. TNEF is a propietary format cooked up in Redmond. When chosen, the e-mail in question isn't sent as text/plain or at least text/html, but the entire e-mail is put into an TNEF-encoded attachment, most often called winmail.dat, in which you (most commonly) find the content of the e-mail in RTF, possible attachments are also put into the winmail.dat. The easieast solution for all involved parties is to convince the sender, that her Outlook and/or Exchange setup needs fixing (disabling TNEF in Outlook and Exchange 2003). Sadly this won't work all the time. The other solutions are to either filter the e-mails on your e-mail server and run them through something like ytnef_smtpd.py (please note, that this might be legally problematic for you as a service provider, opening an e-mail, even automatically, is a violation of communication privacy rights in many jurisdictions). Or, if the legal problem is too big or can't be solved through an local server installation (e.g. because there is no server running 24/7), you're left with either using Outlook (probably what Microsoft intended) or you can use a plug-in/add-on for your client. I've tested the LookOut add-on for icedove and it seems to work well. There are of course plug-ins for many other clients, but I can't honestly tell whether they work or not. [UPDATE 2011-09-20]: Fellow Debian Developer Josselin Mouette wrote me, that Evolution is capable of reading TNEF-encoded e-mails out of the box, but he also said that [TNEF e-mails should] be banned by all means.[/UPDATE 2011-09-20] Now, before I close, please always try to convince the sender/postmaster to fix their setup. It has only advantages: text/plain e-mails are smaller, they're less likely to contain malicious code (i.e. no parts hidden away from the virus scanner on the mail server (amavis can read TNEF e-mails, if libconvert-tnef-perl is installed)) and all recipients can open the e-mails with the client of their choice.

11 September 2011

Julien Valroff: Quick and dirty Debian packages for various kernel modules

As I own several more or less recent laptops, some of their features require updated/new kernel modules to work as expected. I have hence decided to create Debian packages for them, primarily for my own use. Note that these packages are meant to be used with caution, I have only tested them on my own hardware, and they would deserve more careful review. All -source and -dkms packages are available in my personal repository for Debian sid. The sources are maintained in git, as usual.

9 September 2011

Raphaël Hertzog: People behind Debian: Enrico Zini, member of the New Maintainer Frontdesk

Enrico ZiniEven though Enrico is not smiling on this picture, he s one of the friendliest Debian person that I know. I always enjoy his presentations because he can t refrain from inserting jokes or other funny tricks. :-) That said he s serious too, there s lots of good stuff that he has developed over the years (starting with Debtags) and he has put a lot of effort in reforming the New Maintainer process. Read on to learn more about his various projects. Raphael: Who are you? Enrico: Hi, I m Enrico Zini, a DD from Italy. I m 35 and I work as a freelance Free Software developer. One of my historical roles in Debian is taking care of Debtags, but that is not all I do: my paid work led me to write and maintain some weather forecast related software in Debian, and recently I gained a Front Desk hat, and then a DAM hat. Raphael: How did you start contributing to Debian? Enrico: It was 2001, I was at uni, I was using Debian. At some point I wanted to learn packaging so I read through the whole Policy from top to bottom. Then I thought: why package only for myself? . There were many DDs at my uni, and it only seemed natural to me to join Debian as well. Evidently this was also natural for Zack [Note from editor: Stefano Zacchiroli], who had become DD 6 months earlier and didn t hesitate to advocate me. I found the Policy and the Developer s Reference to be very interesting things to read, and I welcomed my AM s questions as an excuse to learn more. I completely understand those people who have fun trying to answer all the questions in the NM templates while they wait for an AM. With my super DAM powers I can see that my AM report was submitted on October 16, 2001 by my AM Martin Michlmayr, and that James Troup created my account 9 days later, on October 25. Raphael: You have a special interest in the New Maintainer (NM) Process since you are a Debian Account Manager (DAM) and a member of the NM Frontdesk. Thanks to your work the process is much less academic/bureaucratic than it used to be. Can you remember us the main changes? Enrico: One of the first things I noticed when I become a Front Desk member is that there was a tendency to advocate people too early, thinking by the time they ll get an AM, they ll know enough . Unfortunately, this didn t always work, and once the real NM process started it would turn into a very long and demotivating experience both for the applicant and for the AM. So we tried raising the bar on advocacies, and that seems to have helped a lot. If people join NM when they are ready, it means that NM is quick and painless both for them and their AMs, who are therefore able to process more applicants. We also did a rather radical cleanup of the NM templates , which are a repository of questions that Application Managers can ask to their applicants. We realized that AMs were just sending the whole templates to their applicants, so we moved all non-essential questions to separate files, to drastically reduce the amounts of questions that are asked by default. Other improvements in the NM process came from other parts of Debian: nowadays there are lots of ways to learn and gradually gain experience and reputation inside the project before joining NM, which means that we get many candidates who we can process quickly. For example, packages can now be uploaded via sponsors, and the Mentors project helps new contributors to find sponsors and get their first packages reviewed. Then one can now become Debian Maintainer and take full responsibility of their own packages, gaining experience and reputation. The idea of working in teams also helped: big teams like the Perl, Python, KDE, Ocaml, Haskell teams (and many more) are excellent entry points for people who have something to package. But Debian is not just for packagers, and one could join teams like the Website team, the Press and Publicity team, the Events and Merchandise team or their local translation team. Becoming DDs the non-uploading way is not just for non-technical people: one could enjoy programming but not packaging. An interesting way to get involved in that way is to help writing or maintaining some of the many Debian services. Note that I m not suggesting this as a way to learn how to program, but as a way to get involved in Debian by writing code. Finally, we started to appreciate the importance of having people activities in Debian explicitly visible, which means that the more obviously good work one has done in Debian, the less questions we need to ask. Jan Dittberner s DDPortfolio is an excellent resource for AMs and Front Desk, and I m maintaining a service called minechangelogs that for people who have done lots of work in Debian is able to fully replace the Tasks&Skills parts of the NM process. Raphael: What are your plans for Debian Wheezy? Enrico: For Wheezy I hope to be able to streamline and simplify Debtags a bit more. At Debconf11 I had a conversation with FTP-masters on how to make some tags more official, and I now have to work a bit more on that. I d also like to considerably downsize the codebase behind the debtags package, now that its job is quite clear and I don t need to experiment with fancy features the way I did in the past. I have to say that I enjoy programming more than I enjoy packaging, so most of my plans in Debian are not tied to releases. For example, I d like to finish and deploy the new NM website codebase soon: it would mean to have a codebase that s much easier to maintain, and in which it s much easier to implement new features. I d also like to design a way to allow maintainers to review the tag submission to their own packages instead of having to wait for me or David Paleino to do a regular review of all the submissions. Finally, I d like to promote the usage of apt-xapian-index in more cutting-edge packaging applications. And to design a way to maintain up to date popcon information in one s local index. And improve and promote those services that I maintain, and I tend to often have ideas for new ones. Raphael: If you could spend all your time on Debian, what would you work on? Enrico: If I could spend all my time on Debian, I would do a lot of software development: I love doing software development, but most of my development energy is spent on my paid work. I guess I would start my all your time in Debian by taking better care of the things that I m already doing, and by promoting them better so that I wouldn t end up being the only person maintaining them. After that, however, I reckon that I do have a tendency of noticing new, interesting problems in need(?) of a solution, and I guess I would end up wildly experimenting new ideas in Debian much like a victorian mad scientist. Which reminds me that I most definitely need minions! Where can I find minions? Raphael: You re the author of the Debian Community Guidelines. I have always felt that this document should be more broadly advertised. For example by integrating it in the Developer s Reference. What do you think? Enrico: The DCG was really a collection of tips to improve one s online communication, based on ideas and feedback that I collected from pestering many experienced and well-respected people for some time. Like every repository of common sense, I think it should be widely promoted but never ever turned into law. It wouldn t be a bad idea to mention it in the Developer s Reference, or to package it as a separate file in the developers-reference package. The reasons I haven t actively been pushing for that to happen are two: there isn t much in the DCG that is specific to Debian, and I don t have the resources to do a proper job maintaining it. It d be great if somebody could take over its maintenance and make it become some proper, widespread, easy-to-quote online reference document, like one of those HOWTOs that all serious people have read at some point in their lives. Raphael: What s the biggest problem of Debian? Enrico: It s sometimes hard to get feedback or help if you work on something unusual. That is partly to be expected, and partly probably due to me not having yet learnt how to get people involved in what I do. Raphael: What motivates you to continue to contribute year after year? Enrico: Debian keeps evolving, so there is always something to learn. And Debian is real, so everything I do is constantly measured against reality. What more intellectual stimulation could one possibly want? Raphael: Is there someone in Debian that you admire for their contributions? Enrico: I don t think I could reasonably list everyone I admire in Debian: pretty much in every corner of the project there is someone, sometimes not very well known, who is putting a lot of Quality in what they do. Someone who decided that X should work well in Debian or that Debian should work well for Y or that Z is something Debian people can rely on and makes sure that it is so. Those are the people who make sure Debian is and will be not just a hobby, but a base upon which I can rely for my personal and working life.
Thank you to Enrico for the time spent answering my questions. I hope you enjoyed reading his answers as I did.

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Wouter Verhelst: SSL and CAs

The CA model of SSL has always bothered me. The idea of a trusted third party feels eerily close to maffia security: you believe this person, whom you don't know, is who he claims he is on nothing more than the word of this other person, whom you also don't know. The DigiNotar story proves how problematic this model is, but you don't really need that to understand its problems. For the longest time, however, there simply was no better way to properly do these things. But now that we have DNSSEC, do we really still need CAs? Really? Can't we just store a fingerprint of a per-domain signing key in the forward (and, possibly, reverse) DNS zone of the host in question, have that signed by DNSSEC, and have the browser check the full DNS chain of the zones in question in addition to the signature on the certificate instead? I'm sure the CA business people would hate to see that happening, but really, paying someone so they say whatever you tell them to say? Try that in court, and they'd lock you up. Update: It's called the DANE protocol. No, that has nothing to do with Denmark: DANE stands for "DNS-based Authentication of Named Entities".

7 September 2011

Soeren Sonnenburg: Shogun at Google Summer of Code 2011

Google Summer of Code 2011 gave a big boost to the development of the shogun machine learning toolbox. In case you have never heard of shogun or machine learning: Machine Learning involves algorithms that do intelligent'' and even automatic data processing and is nowadays used everywhere to e.g. do face detection in your camera, compress the speech in you mobile phone, powers the recommendations in your favourite online shop, predicts solulabily of molecules in water, the location of genes in humans, to name just a few examples. Interested? Then you should give it a try. Some very simple examples stemming from a sub-branch of machine learning called supervised learning illustrate how objects represented by two-dimensional vectors can be classified in good or bad by learning a so called support vector machine. I would suggest to install the python_modular interface of shogun and to run the example interactive_svm_demo.py also included in the source tarball. Two images illustrating the training of a support vector machine follow (click to enlarge): svm svm interactive Now back to Google Summer of Code: Google sponsored 5 talented students who were working hard on various subjects. As a result we now have a new core developer and various new features implemented in shogun: Interfaces to new languages like java, c#, ruby, lua written by Baozeng; A model selection framework written by Heiko Strathman, many dimension reduction techniques written by Sergey Lisitsyn, Gaussian Mixture Model estimation written by Alesis Novik and a full-fledged online learning framework developed by Shashwat Lal Das. All of this work has already been integrated in the newly released shogun 1.0.0. In case you want to know more about the students projects continue reading below, but before going into more detail I would like to summarize my experience with GSoC 2011. My Experience with Google Summer of Code We were a first time organization, i.e. taking part for the first time in GSoC. Having received many many student applications we were very happy to hear that we at least got 5 very talented students accepted but still had to reject about 60 students (only 7% acceptance rate!). Doing this was an extremely tough decision for us. Each of us ended up in scoring students even then we had many ties. So in the end we raised the bar by requiring contributions even before the actual GSoC started. This way we already got many improvements like more complete i/o functions, nicely polished ROC and other evaluation routines, new machine learning algorithms like gaussian naive bayes and averaged perceptron and many bugfixes. The quality of the contributions and independence of the student aided us coming up with the selection of the final five. I personally played the role of the administrator and (co-)mentor and scheduled regular (usually) monthly irc meetings with mentors and students. For other org admins or mentors wanting into GSoC here come my lessons learned: Now please read on to learn about the newly implemented features: Dimension Reduction Techniques Sergey Lisitsyn (Mentor: Christian Widmer) Dimensionality reduction is the process of finding a low-dimensional representation of a high-dimensional one while maintaining the core essence of the data. For one of the most important practical issues of applied machine learning, it is widely used for preprocessing real data. With a strong focus on memory requirements and speed, Sergey implemented the following dimension reduction techniques: See below for the some nice illustrations of dimension reduction/embedding techniques (click to enlarge). isomap swissrollrno kllelocal tangent space alignment Cross-Validation Framework Heiko Strathmann (Mentor: Soeren Sonnenburg) Nearly every learning machine has parameters which have to be determined manually. Before Heiko started his project one had to manually implement cross-validation using (nested) for-loops. In his highly involved project Heiko extend shogun's core to register parameters and ultimately made cross-validation possible. He implemented different model selection schemes (train,validation,test split, n-fold cross-validation, stratified cross-validation, etc and did create some examples for illustration. Note that various performance measures are available to measure how good'' a model is. The figure below shows the area under the receiver operator characteristic curve as an example. foo Interfaces to the Java, C#, Lua and Ruby Programming Languages Baozeng (Mentor: Mikio Braun and Soeren Sonnenburg) Boazeng implemented swig-typemaps that enable transfer of objects native to the language one wants to interface to. In his project, he added support for Java, Ruby, C# and Lua. His knowlegde about swig helped us to drastically simplify shogun's typemaps for existing languages like octave and python resolving other corner-case type issues. The addition of these typemaps brings a high-performance and versatile machine learning toolbox to these languages. It should be noted that shogun objects trained in e.g. python can be serialized to disk and then loaded from any other language like say lua or java. We hope this helps users working in multiple-language environments. Note that the syntax is very similar across all languages used, compare for yourself - various examples for all languages ( python, octave, java, lua, ruby, and csharp) are available. Largescale Learning Framework and Integration of Vowpal Wabbit Shashwat Lal Das (Mentor: John Langford and Soeren Sonnenburg) Shashwat introduced support for 'streaming' features into shogun. That is instead of shogun's traditional way of requiring all data to be in memory, features can now be streamed from e.g. disk, enabling the use of massively big data sets. He implemented support for dense and sparse vector based input streams as well as strings and converted existing online learning methods to use this framework. He was particularly careful and even made it possible to emulate streaming from in-memory features. He finally integrated (parts of) vowpal wabbit, which is a very fast large scale online learning algorithm based on SGD. Expectation Maximization Algorithms for Gaussian Mixture Models Alesis Novik (Mentor: Vojtech Franc) The Expectation-Maximization algorithm is well known in the machine learning community. The goal of this project was the robust implementation of the Expectation-Maximization algorithm for Gaussian Mixture Models. Several computational tricks have been applied to address numerical and stability issues, like An illustrative example of estimating a one and two-dimensional Gaussian follows below. 1D GMM2D GMM Final Remarks All in all, this year s GSoC has given the SHOGUN project a great push forward and we hope that this will translate into an increased user base and numerous external contributions. Also, we hope that by providing bindings for many languages, we can provide a neutral ground for Machine Learning implementations and that way bring together communities centered around different programming languages. All that s left to say is that given the great experiences from this year, we d be more than happy to participate in GSoC2012.

4 September 2011

Sune Vuorela: Network status aware apps

Am I online or not? There is a summary at the end for the quick readers. It is in many modern applications important to be able to more or less gracefully handle if the application user is online or not. For example, there is no need to try to fetch emails if the device (computer, phone, tablet, laptop, ) doesn t have network (wifi, cable, umts, ip over avian carriers, ..). KDE has of course made nice functionality for this, and here I will try to describe how to make your app network status aware and what to be aware of in the process. Solid background All this is going on in Solid, using two parts of Solid and a bit of KDE s infrastructure: The networkstatus KDED module is trying it best to gather information from the computer to see if one is connected or not. It has the possibility to gather information from various sources, and handle changes and such. The as of writing available sources that the networkstatus module gathers information from is Collecting from different sources is important, because some people might have configurations like Manage wireless thru wicd , manage umts dongle with Network Manager and manage wired network with /etc/network/interfaces and all of it needs to be combined. Solid reports, if wicd thinks online , and network manager thinks offline that the user is Connected.. Solid States There is a enum with 5 values in Solid to describe the current state of the network:

enum Status
Unknown,
Unconnected,
Disconnecting,
Connecting,
Connected
;
Connected is the easy state. Here, Solid knows that you are having some kind of connection according to at least one of the sources. But it might just be a local network connection, and not actually a internet connection. So one here should handle connection failures gracefully. Unconnected is a similar easy state. Here, Solid knows that you don t have any internet connection according to the sources it knows about. One should here not try to do any networking. Connecting and Disconnecting is that a state change is happening, so that you can prepare to react on it. Solid also has the state of Unknown, used for cases where Solid doesn t have the required data to actually know it. A example could be a system without any of the data providers. You should here probably try to connect, and be able to handle failures gracefully. Also described as Proceed with caution . The bright reader might here notice that one both in the Unknown and Connected case actually should do the same. Querying for network status At any given time:

Solid::Networking::Status currentStatus = Solid::Networking::status();
if(currentStatus==Connected currentStatus==Unknown)
//try to do networking things
else
//mark application as offline.

Here, we first query Solid for current status, and then if the state is Connected OR Unknown, then we proceed. Getting notified Maybe you don t want the roundtrip of asking (resulting in a dbus rountrip each time) when you need to know the state changes. Then you of course can get notified. class MyNetworkAwareClass : public QObject
Q_OBJECT
public:
MyNetworkAwareClass();
void doNetworkActivity();
private Q_SLOTS:
void networkStatusChanged(Solid::Networking::Status newstatus);
private:
Solid::Networking::Status m_current_state
;
MyNetworkAwareClass::MyNetworkAwareClass : m_current_state(Solid::Networking::Status())
connect(Solid::Networking::notifier(), SIGNAL(statusChanged(Solid::Networking::Status),this,SLOT(networkStatusChanged(Solid::Networking::Status)));

void MyNetworkAwareClass::networkStatusChanged(Solid::Networking::Status newstate)
m_current_state = newstate;
void MyNetworkAwareClass::doNetworkActivity()
if(m_current_state == Unknown m_current_state == Connected)
//try to do network activity


I guess this should be pretty self explaining. Summary Oh. And I m out looking for a job.

29 August 2011

Mike Hommey: Extreme tab browsing

I have a pathological use of browser tabs: I use a lot of them. A lot is probably an understatement. We could say I use them as bookmarks of things I need to track. A couple weeks ago, I was saying I had around two hundred tabs opened. I now actually have much more. It affected startup until I discovered that setting the browser.sessionstore.max_concurrent_tabs pref to 0 was making things much better by only loading tabs when they are selected. This preference has/will become browser.sessionstore.restore_on_demand. However, since I only start my main browser once a day, while other applications start and while I begin to read email, I hadn t noticed that this was still heavily affecting startup time: about:startup tells me reaching the sessionRestored state takes seven seconds, even on a warm startup. It also affects memory usage, because even when tabs are only loaded on demand, there is a quite big overhead for each tab. And more importantly, it gets worse with time. And I think the user interface is actively making it worse. So, to get an idea how bad things were in my session, I wrote a little restartless extension. After installing it, you can go to the about:tabs url to see the damage on your session. Please note that the number of groups is currently wrong until you open the tab grouping interface. This is what the extension has to say about my session 2 days ago, right after a startup: The first thing to note is that when I filed the memory bug 4 days earlier, I had a bit more than 470 tabs in that session. You can see 4 days later, I now have 555 tabs (if excluding the about:tabs tab). The second thing to note is something I suspected because it s so easy to get there: a lot of the tabs are opened on the same address. Since Firefox 4.0, if I m not mistaken, there is a great feature in the awesomebar, that allows to jump to an existing tab matching what you type in the urlbar. That is very useful, and I use it a lot. However, there are a lot of cases where it s not as useful as it could be. One of the addresses I visit a lot is http://buildd.debian.org/iceweasel. It gives me the build status of the latest iceweasel package I uploaded to Debian unstable. That url is particularly known in my browsing history, and is the first hit when I type buildd in the urlbar (actually, even typing b brings it first). Unfortunately, that url redirects to https://buildd.debian.org/status/package.php?p=iceweasel through an HTTP redirection. I say unfortunately because when I type buildd in the urlbar, I get 6 suggestions for urls in the form http://buildd.debian.org/package (I also watch other packages build status), and the suggestion to switch to the existing tab for what the first hit would get me to is 7th. Guess what? The suggestion list only shows 6 items ; you have to scroll to see the 7th. The result is that I effectively have fifteen tabs open on that url. I also keep a lot of bugzilla.mozilla.org bugs open in different tabs. The extension tells me there are 255 of them for 166 unique bugs. Largely, the duplicate bug tabs are due to having these bugs open in some tab, but accessing the same bugs from somewhere else, usually a dependent bug or TBPL. I also have 5 tabs opened on my request queue. I usually get there by going to the bugzilla home page and clicking on the My Requests link. And I have several tabs opened on the same bug lists. For the same reason. When I started using tab groups, I splitted in very distinct groups. Basically, one for Mozilla, one for Debian, one for stuff I want to follow (usually blog posts I want to follow comments from), and one for the rest. While I was keeping up with grouping at the beginning, I don t anymore, and the result is that each group is now a real mess. Firefox has hundreds of millions users. It s impossible to create a user experience that works for everyone. One thing is sure, it doesn t work for me. My usage is probably very wrong at different levels, but I don t feel my browser is encouraging me to use it better, except by making my number of opened tabs explode to an unmanageable level (I already have 30 tabs more than when I started writing this post 2 days ago). There are a few other things I would like to know about my usage that my extension hasn t told me yet, either because it doesn t tell, or because I haven t looked: Reflecting on my usage patterns, I think a few improvements, either in the stock browser, or through extensions, could make my browsing easier: Maybe these exist as extensions, I don t know. It s hard to find very specific things like that through an add-on search (though I haven t searched very hard). [Looks like there is an experiment for the auto tab grouping part] I think it would also be interesting to have something like Test Pilot, but for users that want to know the answer to How do I use my browser? . As I understand it, Test Pilot can show individual user data, but it only can do so if there is such data, and you can t get data for past studies you didn t take. In my case, I m not entirely sure that, apart from the pinned tabs, I use the tab bar a lot. And even for pinned tabs, most of the time I use keyboard shortcuts. I m not using the menu button that much either. I already removed the url and search bar (most of the time) with LessChrome HD. Maybe I could go further and use the full window for web browsing.

8 August 2011

Axel Beckert: Finding libraries not marked as automatically installed with aptitude

This is a direct followup on my blog posting Finding packages for deinstallation on the commandline with aptitude. In the meanwhile on more alias for finding obosolete packages made it into my zsh configuration. It s an alias to find installed libraries, -data, -common and other usually only automatically installed packages, which are not marked as being installed automatically nevertheless:
alias aptitude-review-unmarkauto-libraries='aptitude -o "Aptitude::Pkg-Display-Limit=( ^lib !-dev$ !-dbg$ !-utils$ !-tools$ !-bin$ !-doc$ !^libreoffice   -data$   -common$   -base$ !^r-base ) !~M"'
And yes, this pattern is slightly larger than those from the previous posting, so here s the used filter in a little bit more readable way:
(
  ^lib
    !-dev$
    !-dbg$
    !-utils$
    !-tools$
    !-bin$
    !-doc$
    !^libreoffice   
  -data$   
  -common$   
  -base$
    !^r-base
)
!~M
It matches all non-automatically installed packages whose name starts with lib , but is neither a debug symbols package, a development header package, a documentation package, a package containing supplied commands, nor a libreoffice package. Additionally it matches all non-automatically installed packages ending in -data, -common, or -base, but excludes r-base packages. Of course you can then mark any erroneously unmarked library by pressing M (Shift-m). If you press g for Go afterwards and wonder why nothing to remove shows up, be reminded that the filter limit is active in this view, too. So press l for Limit and then Ctrl-u to erase the current filter limit of this view and press enter to set the new (now empty) filter, et voil Hope this is of help for some others, too.

31 July 2011

Uwe Hermann: The FONIC Surf-Stick, Huawei E1750 HSPA USB modem, on Debian GNU/Linux via usb_modeswitch and wvdial

FONIC Surf-Stick, Huawei E1750, package
I recently got myself a FONIC account for mobile Internet. This (German) prepaid-provider offers a "daily flatrate" for 2.50 per day. After the 10th day of usage (i.e., 25 ) you don't pay any more. This means, even if you need mobile Internet access 31 days a month, you only pay for 10 days. After 500MB/day or 5GB/month you're throttled down to GPRS speed (but you can still connect, and you don't pay more). The FONIC account comes with the "FONIC Surf-Stick", a Huawei E1750 HSPA USB modem (apparently it supports GPRS, EDGE, UMTS, HSDPA (up to 7.2Mbit/s), HSUPA (up to 5.76 Mbit/s), and a SIM card. In order to use the device on Linux you need two packages, usb_modeswitch and wvdial:
  $ apt-get install usb-modeswitch wvdial
Recent versions of usb_modeswitch (and matching udev entries) already support the Huawei E1750 out of the box, a few seconds after attaching the device it's automatically switched into modem mode. After this has been done you should have three new serial devices, usually /dev/ttyUSB0, /dev/ttyUSB1, and /dev/ttyUSB2. You'll need /dev/ttyUSB0 for talking to the device using AT commands. The lsusb output should look like this (see here for full lsusb -vvv):
  $ lsusb
  Bus 001 Device 045: ID 12d1:1436 Huawei Technologies Co., Ltd. 
(before usb_modeswitch was run, the USB IDs were 12d1:1446) FONIC Surf-Stick, Huawei E1750, front The required settings for connecting are documented at fonic.de, specifically the APN (pinternet.interkom.de). A username and/or password is not required. You need to provide your FONIC PIN though. Dialing is done using the *99# number and using the ATDT command. I'm using the following wvdial config file:
  $ cat /etc/wvdial.conf
  [Dialer Defaults]
  Modem = /dev/ttyUSB0
  Baud = 460800
  [Dialer pin]
  Init1 = AT+CPIN=1234
  [Dialer fonic]
  Phone = *99#
  Username = foo
  Password = foo
  Stupid Mode = 1
  Dial Command = ATDT
  Init2 = ATZ
  Init3 = AT+CGDCONT=1,"IP","pinternet.interkom.de"
FONIC Surf-Stick, Huawei E1750, back For mobile Internet access you would do the following:
  1. Attach the device via USB, wait a few seconds to let usb_modeswitch do its magic.
  2. Run wvdial pin and wait a few seconds (until the prompt returns):
      $ wvdial pin
      --> WvDial: Internet dialer version 1.61
      --> Initializing modem.
      --> Sending: AT+CPIN=1234
      AT+CPIN=1234
      OK
      --> Modem initialized.
      --> Configuration does not specify a valid phone number.
      --> Configuration does not specify a valid login name.
      --> Configuration does not specify a valid password.
    
  3. Run wvdial fonic and wait until the "CONNECT" message appears and you get DNS addresses:
      $ wvdial fonic
      --> WvDial: Internet dialer version 1.61
      --> Initializing modem.
      --> Sending: ATZ
      ATZ
      OK
      --> Sending: ATZ
      ATZ
      OK
      --> Sending: AT+CGDCONT=1,"IP","pinternet.interkom.de"
      AT+CGDCONT=1,"IP","pinternet.interkom.de"
      OK
      --> Modem initialized.
      --> Sending: ATDT*99#
      --> Waiting for carrier.
      ATDT*99#
      CONNECT
      --> Carrier detected.  Starting PPP immediately.
      --> Starting pppd at Mon Aug  1 xx:xx:xx 2011
      --> Pid of pppd: 18672
      --> Using interface ppp0
      --> local  IP address xxx.xxx.xxx.xxx
      --> remote IP address yyy.yyy.yyy.yyy
      --> primary   DNS address 193.189.244.225
      --> secondary DNS address 193.189.244.206
    
If everything worked fine you should now have connected successfully. There are other alternatives for achieving the same result, including umtsmon (Qt3 in the last release from 2009, looks a bit unmaintained), kppp, the GNOME NetworkManager, and others, but wvdial worked OK for me. For more details about the Huawei E1750 device (e.g. lsusb -vvv and more photos), see my wiki page at http://randomprojects.org/wiki/FONIC_Surf-Stick_Huawei_E1750 Update 2011-08-03: My measured download speed for a Debian ISO (over HTTP via wget, at night, roughly 22:00 o'clock) is 350-470 KB/s in case anyone is interested. During this download the blue LED on the stick was enabled, which denotes a UMTS connection (green == GPRS/EDGE, turquoise == HSDPA).

24 July 2011

Tore S. Bekkedal: Ut ya: English version

If a single man can display so much hatred
think only of how much love we all can display together.

Stine Renate H heim

I wrote a Norwegian post explaining my experience at Ut ya. I had taken this blog for dead, and had entirely forgotten that it was syndicated on Planet Debian. I don t want to let Google Translate make this disaster any worse than it is the translation of bullets into balls being particularly bad so the international attention the massacre has garnered in consideration, I am writing an English translation of my experiences. I feel somehow duty-bound to make people aware of what happened, but I don t want to get into anything else but a sober description of the events and some very brief reflections. There are many details I have chosen to omit. Others have written their experiences of the events at Ut ya. I wanted to write mine down as well, and get it out there . Partly, I want to write this down because I m unsure if I will remember all the details at a later point in time, although I think I d prefer it if I couldn t. I m also writing this because people are asking about my experiences and it s much better to have an URL to give them, lest I have to keep going through the same spiel over and over again. Our former Prime Minister and current labour movement demigod Gro Harlem Brundtland had recently left the island. I had been the cameraman for a video interview of her talking about Ut ya, and I was in the media group room encoding the video into a file suitable for YouTube, when someone else in the room startled and said that Twitter was full of messages about a loud explosion in Oslo. As the newspapers brought us information about the extent of the damages, a consensus arose that an informational meeting was in order. As soon as the current round of talks finished, we were gathered into the main hall. The meeting was duly held, and after the statement was made that a TV feed would be made available, I took it upon myself as the local alpha geek to make it happen. Of course, the situation caused both the wireless network and the GPRS networks to become totally unusable. As I was waiting for someone to set up a password, I took the opportunity to face the consequences of having eaten two bits of a microwavable dish called Hold-It the local equivalent of a Hot Pocket and went to the toilet. As I was in there, I first heard agitated shouting, then screams, then gunshots coming from just outside the toilets. More than anything else, it sounded like a toy gun. I was convinced that someone was making a joke in incredibly bad taste and I stormed out of the booth with the intent of halting it. As I tore the door open, I saw two of my comrades hiding in a recessed corner. Their facial expressions left absolutely no doubt that this was no toy. They signalled for me to get back in the booth. I closed the door, did a mental double-take in utter, complete confusion, and opened it again. They were still signalling. Had they not stood there, I would have run straight into the gunman; they saved my life. I looked out into the hallway, and I made eye contact with a young boy lying in a pool of blood. He was motioning for me to help him. I heard more gunshots from inside the building and retreated back inside. As I was trying to think through my next move, I realized that the decidedly insubstantial wood-fiber door would not resist any kind of bullets. I made my way out into the hallway, with the intent of escaping outside. At that point, I was of course not aware that there was an intention to kill as many as possible, so I thought that the open spaces outside would be a place of relative safety. Of course, this proved to be wrong and my life was probably saved a second time by one of the caf volunteers taking me into a hard-to-spot employee s bathroom. We sat there for ninety minutes. Always ready to make a run for it, ready for just about anything. A peculiar group dynamic arose with these two people with whom I had barely previously spoken. We came to share a strange sense of common destiny and gallows humour. One of them had seen the shooter and described the police uniform. I perceived it to be realistic that we were the only ones aware of the wounded outside the toilet. I tried to reach the emergency services, but all their lines were busy; the terror attack in Oslo had probably clogged their lines. I finally got through to the fire services, who could inform me that the police did know about the situation and were on their way. This was to take 90 minutes and by the time we evacuated, the young boy outside my door had perished. The despair I first saw in his eyes as I passed him, fleeing from one room to the other and the empty, blank stare as we left, are burned into me and they are images I will never in my life forget. Finally, the real police arrived. We walked out. I chose the path through the minor conference hall something I now regret. The sight was simply beyond my capacity to describe fully, and so terrifying that I barely remember the sight only the terror it struck in me. There were several people bunched up in a corner, a big amorphous heap of bodies. Some were conscious and yelled at me not to do anything that could startle the police, others lay still. Their bodies were all covered in blood, and a thick pool of blood extended at least a half-metre in all directions around them. The policeman across the hall was screaming orders at me, but he was screaming so loudly that I couldn t make out his words at first. We were first moved into the camp newspaper s offices. There were about eight of us there, I think, in addition to one girl who lay wounded. Towards the end she was drifting in and out of consciousness. We covered her with sweaters to keep her warm and one of us tried to at least temper her bleeding. The bullet had missed her heart, but by the entry wound it was clear that it was not by far. I do not know who this girl was or how she is now. I sat behind and never saw her face. The wounded were evacuated first. I don t remember how long we remained; I had lost all concept of time. In spite of protests from the group who knew him, one kid was put in handcuffs. At the time I didn t understand why, and the policeman seemed to say something almost to the effect that there was no reason for it at all. I didn t see when they undid his cuffs, but I remember thinking that this treatment made a terrible experience even worse for him. I tried my best to comfort him but knew it would be little help. Later, when things stabilised a little, we were told that he was handcuffed because he had come from an unsecured area. The police was extremely good at carefully explaining what was happening and why; this was a big help and I am grateful for it. Eventually we were moved out into the main corridor of the building, where we joined up into a group of about fifty. Only when I saw the two people who saved my life did any emotion other than mild confusion arise. I broke down shivering in tears in one of their arms. After a few seconds, I came back to my senses and realised that this was not the time. I quickly gathered myself, got the shaking under control, and sat down. We were given some chocolate and soda from the kiosk. I remember making an offhand remark that an inability to find joy in free candy was a sure sign of a bad situation. We all laughed out loud. Gallows humour is a coping mechanism, but in retrospect one almost feels guilty for it. We were shown out in a single file with hands above our heads. I remember an intense concern that someone would slip in the steep, muddy slope and create a misunderstanding. Outside, there were more bodies. Some under improvised covers a tarpaulin from the waffle stand, the deflated bouncy castle but some simply lay there. Everyone I met displayed a courage, a mental discipline and unity of purpose far beyond anything one would ever wish to expect from people this young. Everyone conducted themselves with an attitude that could almost be described as stiff upper lip . Safely across the fjord we were offered blankets. I was asked if I was aware of any injuries, and asked to lift my shirt and show my abdominal region. We were shown into the bus which took us to the hotel used by the survivors and their family. I simply cannot describe in any words the relief I felt when I was able to embrace my living comrades. It was completely unlike anything I had ever felt before in my life. The euphoric feeling was tempered only by the realisation that there would be many I could never see again, comrades whom I had taken great pride in calling my friends, with futures in the service of all mankind, futures I had previously found such great joy in pondering and guessing about. The feeling which continues to upset me the most, is the feeling that so many of my comrades left behind grieving families and friends. Torn away senselessly. I do not know how much more than this relatively sober account of the events on Ut ya I can muster. I would, however, like to offer some reflections. First of all, from the bottom of my heart, I want to thank the police who saved the lives of so many still on the island, the holidaymakers who took aboard swimmers into their boats and the rescue services staffed primarily by volunteers who have spared no effort in trying to soften the blow as much as they can. The opportunity to spend time with those comrades who underwent the same experience as myself has also been an immeasurable aid. I was also so relieved to find my very closest friend among the survivors, which has also been an indescribable help. If I can name a single positive in this tragedy: Had he arrived with his automatic weapon fifteen or twenty minutes prior, he would have arrived during the informational meeting, at a time when the major hall was absolutely jam-packed the death toll would be many times what it ended up being. I am agonisingly aware of the meager comfort this provides to those who have been bereft of their closest, but I do find some solace in this. We cannot sweep under a rug that this was without question! a political attack on the labour movement. But it is thankfully also an attack which has been perceived by everyone as an attack on the Norwegian society, and on a symbol of the wide recruitment to the participatory democracy which lies at our very national soul. I cannot thank the Norwegian people, and indeed the people in other nations who have offered their condolences, enough for their shows of support and shared grief. It really has been a tremendous help to me knowing that so many people feel with us. I also want to thank from the bottom of my heart the rock-steadiness of everyone in both the national and local wings of the Labour Party and Labour Youth in supporting us, and the political milieu in general for their resolute steadfastness saving me from losing yet more that I cherish; our freedoms in a participatory democracy. Our Party has lost many of its very brightest youngsters. Personally I feel an angry spite, a deep restless urge to get the wheels of society going again. I want to show his kind that we will not be broken. We re stronger than that. I will not be frightened into silence and passivity. I want to remember the dead, and honor them by carrying on our common work. I want to end this with a request to everyone who reads this, echoing a statement I read by one of my good friends and comrades: Please, don t let me see any messages of hatred, wishes for the death penalty, anything like that. If anyone should be of the belief that anything will improve by murdering this sad little person, they would be profoundly wrong. All attention now should be plowed into caring for those victims and their relatives who did not share my luck, and not giving an audience to a perpetrator who wants one. Tore Sinding Bekkedal

15 July 2011

Dirk Eddelbuettel: MCMC and faster Gibbs Sampling using Rcpp

Sanjog Misra, who uses Rcpp for Monte Carlo Markov Chain (MCMC) analyses in quantitative marketing, kindly set me a short example of Rcpp use. The example is based on a blog post by Darren Wilkinson which itself discusses and compares the suitability of R, Python, Java or C for MCMC analysis, using the Gibbs sampler as a concrete example. Darren's post is worth checking out: he stresses the rather pragmatic aspects of how fast and/or easy it is to write the code, rather than just the mere runtime. As such, he is not too concerned with a speed advantage of Python over R which he sees at a factor of around 2.4, leaving him to continue to prototype in R. Similarly, with C 'only' being faster than Java by a factor of two, he prefers Java for the numerically more demanding parts. We do of course advocate the use of Rcpp to combine the best aspects of R and C++, respectively. This Gibbs sampler example provides a nice backdrop. So working with Darren's example, consider the same Gibbs sampler for a bivariate distribution (and apologies for the lack of latex typesetting on my blog)
f(x,y) = k x^2 exp( -x y^2 - y^2 + 2y - 4x)
where the conditional distributions are
f(x y) = (x^2)*exp(-x*(4+y*y))               ## a Gamma density kernel
f(y x) = exp(-0.5*2*(x+1)*(y^2 - 2*y/(x+1))  ## a Gaussian kernel
Sanjog then spotted and corrected a small error in the variance expression in Darren's derivation; this is now acknowledged on Darren's website. Full details are in the R script now committed in SVN. The R code for the Gibbs sample can therefore be written as follows below. Note that this uses thinning to minimize serial correlation in the conditional densities--which renders the computation more demanding as 'N times thin' draws have to be generated:
## Here is the actual Gibbs Sampler
## This is Darren Wilkinsons R code (with the corrected variance)
## But we are returning only his columns 2 and 3 as the 1:N sequence
## is never used below
Rgibbs <- function(N,thin)  
    mat <- matrix(0,ncol=2,nrow=N)
    x <- 0
    y <- 0
    for (i in 1:N)  
        for (j in 1:thin)  
            x <- rgamma(1,3,y*y+4)
            y <- rnorm(1,1/(x+1),1/sqrt(2*(x+1)))
         
        mat[i,] <- c(x,y)
     
    mat
 
A second variant can be computed using the R bytecode compiler which appeared with the recent release of R 2.13.0 (and which we analysed in this blog post from April). This is as easy as
## We can also try the R compiler on this R function
RCgibbs <- cmpfun(Rgibbs)
Thanks to Rcpp and the inline package, we can also write a C++ variant that can be built and launched from R with ease. The C++ code is assigned to an R text variable gibbscode. (And we used to typeset such code on the blog as a character string, ie in a faint red color---but have now switched to highlight it as if it were freestanding C++ code. It really is passed as a single string to R which then uses the cxxfunction() to compile, link and load a C++ function built around the code. See previous posts on the inline package for more.)
## Now for the Rcpp version -- Notice how easy it is to code up!
gibbscode <- '

  using namespace Rcpp;   // inline does that for us already
  // n and thin are SEXPs which the Rcpp::as function maps to C++ vars
  int N   = as<int>(n);
  int thn = as<int>(thin);
  int i,j;
  NumericMatrix mat(N, 2);
  RNGScope scope;         // Initialize Random number generator
  // The rest of the code follows the R version
  double x=0, y=0;
  for (i=0; i<N; i++)  
    for (j=0; j<thn; j++)  
      x = ::Rf_rgamma(3.0,1.0/(y*y+4));
      y = ::Rf_rnorm(1.0/(x+1),1.0/sqrt(2*x+2));
     
    mat(i,0) = x;
    mat(i,1) = y;
   
  return mat;             // Return to R
'
# Compile and Load
RcppGibbs <- cxxfunction(signature(n="int", thin = "int"),
                         gibbscode, plugin="Rcpp")
It is noteworthy how the code logic is essentially identical between the basic R version, and the C++ version. Two nested loops control draws of x from a Gamma distribution, conditional on y, as well as draws of y from a Normal, conditional on x. Add a small amount of parameter passing to obtain the parameters N and thin, allocation of a results matrix and setup of the random number generator state to remain consistent with R, as well as a return of the matrix---and that is all. As Darren's code uses the GNU GSL in its C variant, I also became interested in seeing how a C/C++ hybrid variant using our RcppGSL package would fare. The code is below.
gslgibbsincl <- '
  #include <gsl/gsl_rng.h>
  #include <gsl/gsl_randist.h>
  using namespace Rcpp;  // just to be explicit
'
gslgibbscode <- '
  int N = as<int>(ns);
  int thin = as<int>(thns);
  int i, j;
  gsl_rng *r = gsl_rng_alloc(gsl_rng_mt19937);
  double x=0, y=0;
  NumericMatrix mat(N, 2);
  for (i=0; i<N; i++)  
    for (j=0; j<thin; j++)  
      x = gsl_ran_gamma(r,3.0,1.0/(y*y+4));
      y = 1.0/(x+1)+gsl_ran_gaussian(r,1.0/sqrt(2*x+2));
     
    mat(i,0) = x;
    mat(i,1) = y;
   
  gsl_rng_free(r);
  return mat;           // Return to R
'
## Compile and Load
GSLGibbs <- cxxfunction(signature(ns="int", thns = "int"),
                        body=gslgibbscode, includes=gslgibbsincl,
                        plugin="RcppGSL")
This code is similar to the version using just Rcpp, but we need to allocate space for the GSL random generator object (and later release that memory allocation), and we do of course call the GSL functions. This also necessitates declaring the function using the two header files listed as arguments for the include argument of cxxfunction(). So how is the performance? The script (now committed in Rcpp's SVN repo as examples/RcppGibbs/RcppGibbs.R, and also part of the next release) creates the output below when running in non-interactive mode (whereas interactive mode creates a few charts too):
edd@max:~/svn/rcpp/pkg/Rcpp/inst/examples/RcppGibbs$ r RcppGibbs.R
Replication # 1 complete 
Replication # 2 complete 
Replication # 3 complete 
Replication # 4 complete 
                    N=1000 N=5000 N=10000 N=20000
Elasped Time (R)     0.124  2.650  10.511  41.773
Elasped Time (RC)    0.081  1.916   7.594  30.280
Elapsed Time (Rcpp)  0.003  0.076   0.306   1.221
Elapsed Time (Rgsl)  0.002  0.049   0.196   0.784
SpeedUp Rcomp.       1.530  1.380   1.380   1.380
SpeedUp Rcpp        41.330 34.870  34.350  34.210
SpeedUp GSL         62.000 54.080  53.630  53.280
               test replications elapsed  relative user.self sys.self
4  GSLGibbs(N, thn)           10   7.845  1.000000      7.84        0
3 RcppGibbs(N, thn)           10  12.218  1.557425     12.22        0
2   RCgibbs(N, thn)           10 312.296 39.808286    311.98        0
1    Rgibbs(N, thn)           10 420.953 53.658764    420.59        0
The first block is a hand-computed comparison using four sets of parameters; the second block uses the excellent rbenchmark package to compare ten runs at twenty-thousand draws. We see a nominal increase in performance due to the bytecode compiler, saving roughly 38 percent which seems appropriate given that the R code mostly controls the loops; actual work in undertaken in the already compiled RNG functions. The Rcpp variant is about 34 times faster than the pure R code. Sanjog reported higher increases on his OS X machines (and Darren's post echos a similar order of magnitude). However, on my i7 running Linux I always obtained an improvement in the mid- to high thirties. That is certainly already a rather pleasant result. What surprised and stunned me at first was that the GSL solution scores an improvement of around 53 times (close to the factor of 60 reported by Darren). A closer look at the code (shown above) makes it clear that there are very few compute-intensive operations outside of the RNG draws. I validated this further with a second study timing just one million draws each from a Gaussian and Gamma using R via Rcpp, and using the GSL. It turns out that the R code is about 2.5 times slower for random draws from the Gamma distribution than the GSL. Inspection of the source code---in files src/nmath/rgamma.c for R and randist/gamma.c for the GSL shows why. R uses a much more complex (and presumably more precise) algorithm. I may follow up with Martin Maechler to see if we can illustrative the numerical benefits of this more expensive approach---this blog entry is getting long enough already. So to sum up: Gibbs sampling is a somewhat resource-heavy Monte Carlo Markov Chain method for investigating multivariate distributions. R excels at quick and simple explorations, albeit at somewhat slower execution speed. The Rcpp package can help by providing easy means to accelerate simulations by a significant factor. The example discussed here is now in SVN repository for Rcpp and will be part of the next release.

Updated 2011-07-16: Darren has just updated his comparison; fixed two typos here too.

14 July 2011

Rapha&#235;l Hertzog: How to squash Debian release critical bugs

Squashing release critical (RC) bugs is one of the most helpful way to contribute to Debian. Because those are the bugs that we need to get rid of in order to release the next stable version. Let s see how you can help. The process is really simple:
  1. Find a RC bug that you can fix
  2. Prepare a fixed package
  3. Send the patch to the BTS
  4. Get your fixed package uploaded
I have already covered points 2 and 3 in a former article: How to prepare patches for Debian packages. So I m not going to repeat myself in this article, instead I ll cover how to find a release critical bug to fix and how to get your package uploaded. Find a RC bug with UDD The Ultimate Debian Database (UDD) provides a neat interface to query the bug tracking system: http://udd.debian.org/bugs.cgi. The form contains many options to customize the query, we ll try explain some. First, at the top, you can decide to list bugs based on whether or not they affect testing/stable/unstable. Indeed, thanks to version tracking the BTS knows if a bug applies to the version of the package present in a given distribution. I suggest you pick a choice that includes sid because that s where you re going to push your fixed package. If sid is not affected by the bug, you can t do much about it (except if you want to join the release team and help ensure updates are flowing from unstable to testing). I usually go for wheezy and sid because that filters out packages which are not in testing (and are thus not blocking the next release). Then you have lots of filters to further reduce the list of bugs. It s important to reduce the noise as you typically have several hundreds of RC bugs at a given time. I suggest you the following settings for a start, but you re free to try other combinations depending on what you want to achieve (I ll give some examples later):
  • ignore bugs tagged patch (a fix is already available);
  • ignore bugs tagged pending (a fix has already been committed to the VCS repository);
  • ignore bugs newer than 7 days (that s the time we should leave for the maintainer to take care of the bug by himself);
I usually sort the results by source package so that I immediately see if several RC bugs are affecting the source package. And I might add popularity contest information to get a feel of whether the package is widely used or not. You can see the results of the suggested query here. Other interesting queries: Find a RC bug with rc-alert The downside of the above method is that you get bugs on packages that you don t know at all and that you might not care about. Some of them might even be better removed instead of fixed. With the rc-alert command (provided by the devscripts package), you will get a list of RC bugs
on packages that are installed on your computer. It should be much more restrictive. And you have command line options to further filter the list just like with the UDD form. Bonus feature: you can also filter by debtags allowing you to restrict the bugs to packages which are implemented in programming languages that you know.
$ rc-alert --include-dists TU --exclude-tags P+ --debtags implemented-in::perl,implemented-in::python
Package: gwibber
Bug:     608724
Title:   gwibber bypasses certificate checking when providing the login/password for OAuth
Flags:   [     S  ] (security)
Dists:   [STU] (stable, testing, unstable)
Debtags: implemented-in::python, interface::x11, role::program, uitoolkit::gtk, works-with::im, x11::application
[...]
Get your fixed package uploaded Usually sending the patch to the BTS is more than enough. The maintainer or another Debian developer will pick it up at some point. But if you re interested in becoming a Debian maintainer/developer, it might be worth to push your changes more quickly and get credited by a proper upload with your name. Instead of just preparing a patch, you should also prepare a fixed package following the rules of a Non-Maintainer Upload. Put this package somewhere online (for example on mentors.debian.net). When you send your patch to the BTS, include the link to the updated package and express your wish to get this update sponsored. If you haven t heard anything from the maintainer after 2-3 days, try to find a sponsor on debian-mentors@lists.debian.org. NMUs are easier to review than completely new packages and many Debian developers like to kill RC bugs, so there s a good chance that you ll find someone. Now happy RC bug-squashing! And if you really enjoy it, you can subscribe to debian-bugs-rc (~3000 mails per month) :-)
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10 July 2011

NeuroDebian: NeuroDebian@HBM2011.ca

NeuroDebian@HBM2011.ca On June 26-30 the annual meeting of the Organization for Human Brain Mapping (HBM2011) took place in Quebec City, Canada. Encouraged by our positive experience at last year s SfN in San Diego and enthusiasm of our scientific adviser, James V. Haxby, we hosted another NeuroDebian booth. The setup was pretty much the same as last year: Some chairs and tables, lots of people, our tri-fold flyers, a Debian mirror and some virtual machine images to show Debian in action. This time we also had an LCD display attracting visitors with the package swarm, some demos, and our recent paper. We had many curious people have their first exposure to Debian, long-time users expressing their gratitude to Debian, and our upstream developers getting together to discuss various topics. Having registered the booth as NeuroDebian , we had the additional pleasure of explaining visitors the concept of a project inside Debian, in contrast to a derived distribution. But that is nothing new really, so let s talk about the differences from last year s booth. First of all, we had more people at the booth. Dominique Belhachemi volunteered to help us out and that was very much appreciated. Although HBM has only about a tenth of the attendees that SfN has, we had significantly more traffic. While last year people were primarily interested in knowing about the project, this time many of them wanted to give it a try immediately. People came with their laptops, got the VM images and started playing with Debian. After a day or so, some came back and asked for recommendations on particular software after having been exposed to the wealth of the Debian archive. What also had increased was the number of developers, or rather research labs developing neuroimaging software that came to the booth to discuss how to get their software into Debian and how to arrange ongoing maintenance of these future Debian packages. As we have our plates already quite full, we have been spending some time on mentoring interested developers to learn the art of Debian packaging and making them familiar with Debian s procedures and standards (e.g. working on #609820 with Yannick Schwartz, upstream, at the booth). ../../_images/BusyBooth216.jpg Two promising new developments need to be mentioned. First, we were approached by companies that develop hardware for brain-imaging and psychophysics research. They were curious to learn about Debian as an integrated platform that offers free software solutions that an increasing amount of their customers demands (e.g. PsychoPy). Apparently, the movement towards open research software has finally made it into the business plans of companies, as they seem to start perceiving compatibility with free software systems as a competitive advantage. We explained how software gets into Debian, and how its release cycle is managed. To foster their motivation we also pointed them to the existing open-source software that is already available or even present in Debian. Let s see whether we see more Debian-certified research products in the future. Lastly, we started talking with folks from the INCF to explore possibilities of collaborating on INCF projects using Debian as the integration and development platform. The INCF is an OECD-funded organization that develops collaborative neuroinformatics infrastructure and promotes the sharing of data and computing resources to the international research community. At least one INCF project is already relying on the efforts of the NeuroDebian project. We are going to continue this discussion during a workshop in September. A report will follow...
../../_images/DDs13.jpg

Debian people at the booth (f.l.t.r): Michael Hanke, Yaroslav Halchenko, Stephan Gerhard, Dominique Belhachemi. Not shown: Swaroop Guntupalli.

Acknowledgments This booth has been made possible by the generous support of Prof. James V. Haxby (Dartmouth College, New Hampshire, USA).

1 July 2011

Matthew Palmer: Metablogging

I ve taken the plunge, and converted my blog from a venerable but largely unmaintain(ed able) blosxom setup that I ve had since 2005 (OMG!) into a new and shiny Jekyll-backed system. The main benefits are that I m more comfortable hacking away at Jekyll (being written in Ruby), and my blog post submission no longer requires me to e-mail my blog posts to myself to put them up (that was just an artifact of how I set it up all those years ago, but it had worked so I wasn t willing to change it just for the sake of it). Jekyll s superior (for me) hackability has reaped dividends already I ve put together a home-grown comments system, which fulfils my primary requirements of being as close to completely statically-generated as it s possible to be (about 10 lines of PHP is the only dynamic content), and doesn t involve JavaScript or putting my blog comments in the cloud .

16 June 2011

Olivier Berger: Debian business card made with GLabels

Unfortunately, GLabels is currently unmaintained. Still, it's a very convenient tool, IMHO to print DIY business cards. Here's my glabels business card file, for those interested to borrow and reuse it.

12 June 2011

Christian Perrier: Developers per country (June 2011) - 3rd take

See comments at the end about this 3rd version This is time again for yet another bubulle game: counting the number of developers per country. I already published such analysis in 2010 and 2009. So, here we are with the June 2011 version, sorted by the ratio of *active* developers per million population for each country.
Act: number of active developers
Dev: total number of developers
A/M: number of active devels per million pop.
D/M: number of devels per million pop.
2009: rank in 2009
2010: rank in 2010
June 2011: rank now
Code Name Population Act Dev Dev Act/Million Dev/Million 2009 2010 June 2011
fi Finland 5374781 21 31 3,91 5,77 1 1 1
ch Switzerland 7866500 21 26 2,67 3,31 2 2 2
mq Martinique 397730 1 1 2,51 2,51

3
no Norway 4964500 12 15 2,42 3,02 5 4 4
nz New Zealand 4393500 10 15 2,28 3,41 4 3 5
ie Ireland 4470700 10 13 2,24 2,91 13 9 6
se Sweden 9354462 19 35 2,03 3,74 3 6 7
lu Luxemburg 511840 1 1 1,95 1,95 8 5 8
de Germany 81802000 155 221 1,89 2,7 7 7 9
at Austria 8404252 15 25 1,78 2,97 6 8 10
fr France 63136180 91 119 1,44 1,88 12 12 11
au Australia 22632213 31 57 1,37 2,52 9 10 12
be Belgium 11007020 15 17 1,36 1,54 10 11 13
uk United-Kingdom 62008048 67 106 1,08 1,71 14 14 14
nl Netherlands 16674600 18 37 1,08 2,22 11 13 15
dk Denmark 5564219 6 10 1,08 1,8 17 17 16
ca Canada 34480000 27 57 0,78 1,65 15 15 17
hr Croatia 4429078 3 3 0,68 0,68 20 18 18
es Spain 46030109 31 51 0,67 1,11 16 16 19
lt Lithuania 3225346 2 2 0,62 0,62 28 19 20
cz Czech Rep 10540748 6 6 0,57 0,57 21 20 21
it Italy 60605053 33 47 0,54 0,78 23 22 22
bg Bulgaria 7351254 4 4 0,54 0,54 25 23 23
il Israel 7602400 4 6 0,53 0,79 24 24 24
us USA 308745538 162 364 0,52 1,18 19 21 25
hu Hungary 9979000 5 11 0,5 1,1 18 25 26
lv Latvia 2245357 1 1 0,45 0,45 26 26 27
uy Uruguay 3494382 1 2 0,29 0,57 22 27 28
jp Japan 127960000 33 46 0,26 0,36 30 28 29
pl Poland 38186860 9 13 0,24 0,34 29 29 30
cr Costa Rica 4253897 1 1 0,24 0,24 31 30 31
pt Portugal 10647763 2 4 0,19 0,38 27 32 32
sk Slovakia 5429763 1 1 0,18 0,18 32 31 33
gr Greece 11305118 2 3 0,18 0,27 33 38 34
ar Argentina 40091359 7 9 0,17 0,22 34 33 35
sv El Salvador 6134000 1 1 0,16 0,16

36
tw Taiwan 23061689 3 3 0,13 0,13 37 34 37
br Brazil 190732694 20 21 0,1 0,11 36 35 38
by Belarus 9648533 1 1 0,1 0,1 35 36 39
mg Madagascar 20653556 2 2 0,1 0,1 44 37 40
cu Cuba 11239363 1 1 0,09 0,09
38 41
kr South Korea 48758000 4 6 0,08 0,12 39 39 42
ec Ecuador 14790608 1 1 0,07 0,07
40 43
cl Chile 17224200 1 2 0,06 0,12 42 41 44
ro Romania 21466174 1 2 0,05 0,09 45 43 45
co Colombia 45925397 2 3 0,04 0,07 41 44 46
ru Russia 142905200 6 7 0,04 0,05 43 42 47
za South Africa 49991300 2 9 0,04 0,18 38 48 48
my Malaysia 27565821 1 1 0,04 0,04

49
ve Venezuela 29105632 1 1 0,03 0,03 40 45 50
pe Peru 29496000 1 1 0,03 0,03 46 46 51
tr Turkey 73722988 2 2 0,03 0,03 47 47 52
mx Mexico 112322757 2 2 0,02 0,02 49 49 53
th Thailand 63878267 1 2 0,02 0,03 50 50 54
eg Egypt 80085862 1 3 0,01 0,04 51 51 55
in India 1210193422 8 8 0,01 0,01 52 52 56
cn China 1339724852 7 11 0,01 0,01 53 53 57
ua Ukraine 45888000 0 0 0 0 48 53 58























896 1450 61,79%



A few interesting facts:
  • There are active DDs in 57 countries
  • Martinique pops up at rank 3. As this French overseas "d partement" has its own ISO code, it is counted here separately from France, though Martinique inhabitants are French citizens. That's of course a though case but I consider that David did choose to use "MQ" in his record, which means this is important for him. Let's respect that wish.
  • Norway is now ahead of New Zealand. One more DD since last count
  • Sweden is ahead of Luxembourg. Two more DDs since last count
  • France takes over Australia and Belgium. *seven* more DDs since last count!
  • UK is ahead of Netherlands now. Three more DDs since last count.
  • Denmark passes Canada and Spain (50% more DDs for DK), while Croatia passes Spain (because Spain lost 3 DDs).
  • USA continues to go down (by 3 this time). We're constantly losing developers over there (-3 in one year).
  • And we have a new country in this list as Malaysia now has a Debian developer. Along with Martinique (ahem), this makes two new "countries" in this list. No country disappeared.
  • For the first time in 12 years, DebConf will be in a country (Bosnia and Herzegovina) that has NO Debian developer. This has to change.
  • We have 23 more active Debian developers and 40 more developers overall.
v2 comment: This is the second version of this blog post. I have been pointed that the population I was using for "Ireland" is indeed the population of the entire island, so Republic of Ireland (Eire) plus Northern Ireland (Ulster). We may guess that people listing "IE" as their country are citizens of the Republic of Ireland, so the population to use is that of this part of the island. As a consequence, Ireland is bumped up to 6th rank instead of 9th. v3 comment: Doh. Since I'm doing this survey, I was always adding people using "sv" as country to Sweden. This is a quite common mistake and it was happening in the past. But now, there is only ONE developer who uses "sv" as country, this is Rene Mayorga and he definitely lives in El Salvador, not Sweden. As a consequence, Sweden lost one developer (but keeps its rank) and El Salvador now appears at rank 36. It is not a "new" country as Rene is DD for quite some time.

11 June 2011

Christian Perrier: Developers per country (June 2011) - 2nd take

See comment at the end about this 2nd version This is time again for yet another bubulle game: counting the number of developers per country. I already published such analysis in 2010 and 2009. So, here we are with the June 2011 version, sorted by the ratio of *active* developers per million population for each country.
Act: number of active developers
Dev: total number of developers
A/M: number of active devels per million pop.
D/M: number of devels per million pop.
2009: rank in 2009
2010: rank in 2010
June 2011: rank now
Code Name Population Act Dev Dev Act/Million Dev/Million 2009 2010 June 2011
fi Finland 5374781 21 31 3,91 5,77 1 1 1 1
ch Switzerland 7866500 21 26 2,67 3,31 2 2 2 2
mq Martinique 397730 1 1 2,51 2,51

3 3
no Norway 4964500 12 15 2,42 3,02 5 4 4 4
nz New Zealand 4393500 10 15 2,28 3,41 4 3 5 5
ie Ireland 4470700 10 13 2,24 2,91 13 9 6 6
se Sweden 9354462 20 36 2,14 3,85 3 6 7 7
lu Luxemburg 511840 1 1 1,95 1,95 8 5 8 8
de Germany 81802000 155 221 1,89 2,7 7 7 9 9
at Austria 8404252 15 25 1,78 2,97 6 8 10 10
fr France 63136180 91 119 1,44 1,88 12 12 11 11
au Australia 22632213 31 57 1,37 2,52 9 10 12 12
be Belgium 11007020 15 17 1,36 1,54 10 11 13 13
uk United-Kingdom 62008048 67 106 1,08 1,71 14 14 14 14
nl Netherlands 16674600 18 37 1,08 2,22 11 13 15 15
dk Denmark 5564219 6 10 1,08 1,8 17 17 16 16
ca Canada 34480000 27 57 0,78 1,65 15 15 17 17
hr Croatia 4429078 3 3 0,68 0,68 20 18 18 18
es Spain 46030109 31 51 0,67 1,11 16 16 19 19
lt Lithuania 3225346 2 2 0,62 0,62 28 19 20 20
cz Czech Rep 10540748 6 6 0,57 0,57 21 20 21 21
it Italy 60605053 33 47 0,54 0,78 23 22 22 22
bg Bulgaria 7351254 4 4 0,54 0,54 25 23 23 23
il Israel 7602400 4 6 0,53 0,79 24 24 24 24
us USA 308745538 162 364 0,52 1,18 19 21 25 25
hu Hungary 9979000 5 11 0,5 1,1 18 25 26 26
lv Latvia 2245357 1 1 0,45 0,45 26 26 27 27
uy Uruguay 3494382 1 2 0,29 0,57 22 27 28 28
jp Japan 127960000 33 46 0,26 0,36 30 28 29 29
pl Poland 38186860 9 13 0,24 0,34 29 29 30 30
cr Costa Rica 4253897 1 1 0,24 0,24 31 30 31 31
pt Portugal 10647763 2 4 0,19 0,38 27 32 32 32
sk Slovakia 5429763 1 1 0,18 0,18 32 31 33 33
gr Greece 11305118 2 3 0,18 0,27 33 38 34 34
ar Argentina 40091359 7 9 0,17 0,22 34 33 35 35
tw Taiwan 23061689 3 3 0,13 0,13 37 34 36 36
br Brazil 190732694 20 21 0,1 0,11 36 35 37 37
by Belarus 9648533 1 1 0,1 0,1 35 36 38 38
mg Madagascar 20653556 2 2 0,1 0,1 44 37 39 39
cu Cuba 11239363 1 1 0,09 0,09
38 40 40
kr South Korea 48758000 4 6 0,08 0,12 39 39 41 41
ec Ecuador 14790608 1 1 0,07 0,07
40 42 42
cl Chile 17224200 1 2 0,06 0,12 42 41 43 43
ro Romania 21466174 1 2 0,05 0,09 45 43 44 44
co Colombia 45925397 2 3 0,04 0,07 41 44 45 45
ru Russia 142905200 6 7 0,04 0,05 43 42 46 46
za South Africa 49991300 2 9 0,04 0,18 38 48 47 47
my Malaysia 27565821 1 1 0,04 0,04

48 48
ve Venezuela 29105632 1 1 0,03 0,03 40 45 49 49
pe Peru 29496000 1 1 0,03 0,03 46 46 50 50
tr Turkey 73722988 2 2 0,03 0,03 47 47 51 51
mx Mexico 112322757 2 2 0,02 0,02 49 49 52 52
th Thailand 63878267 1 2 0,02 0,03 50 50 53 53
eg Egypt 80085862 1 3 0,01 0,04 51 51 54 54
in India 1210193422 8 8 0,01 0,01 52 52 55 55
cn China 1339724852 7 11 0,01 0,01 53 53 56 56
ua Ukraine 45888000 0 0 0 0 48 53 57 57

























896 1450 61,79%




A few interesting facts:
  • Martinique pops up at rank 3. As this French overseas "d partement" has its own ISO code, it is counted here separately from France, though Martinique inhabitants are French citizens. That's of course a though case but I consider that David did choose to use "MQ" in his record, which means this is important for him. Let's respect that wish.
  • Norway is now ahead of New Zealand. One more DD since last count
  • Sweden is ahead of Luxembourg. Two more DDs wince last count
  • France takes over Australia and Belgium. *seven* more DDs since last count!
  • UK is ahead of Netherlands now. Three more DDs since last count.
  • Denmark passes Canada and Spain (50% more DDs for DK), while Croatia passes Spain (because Spain lost 3 DDs).
  • USA continues to go down (by 3 this time). We're constantly losing developers over there (-3 in one year).
  • And we have a new country in this list as Malaysia now has a Debian developer. Along with Martinique (ahem), this makes two new "countries" in this list. No country disappeared.
  • For the first time in 12 years, DebConf will be in a country (Bosnia and Herzegovina) that has NO Debian developer. This has to change.
  • We have 23 more active Debian developers and 40 more developers overall.
This is the second version of this blog post. I have been pointed that the population I was using for "Ireland" is indeed the population of the entire island, so Republic of Ireland (Eire) plus Northern Ireland (Ulster). We may guess that people listing "IE" as their country are citizens of the Republic of Ireland, so the population to use is that of this part of the island. As a consequence, Ireland is bumped up to 6th rank instead of 9th.

Christian Perrier: Developers per country (June 2011)

This is time again for yet another bubulle game: counting the number of developers per country. I already published such analysis in 2010 and 2009. So, here we are with the June 2011 version, sorted by the ratio of *active* developers per million population for each country.
Act: number of active developers
Dev: total number of developers
A/M: number of active devels per million pop.
D/M: number of devels per million pop.
2009: rank in 2009
2010: rank in 2010
June 2011: rank now
Code Name Population Act Dev Dev Act/Million Dev/Million 2009 2010 June 2011
fi Finland 5374781 21 31 3,91 5,77 1 1 1
ch Switzerland 7866500 21 26 2,67 3,31 2 2 2
mq Martinique 397730 1 1 2,51 2,51

3
no Norway 4964500 12 15 2,42 3,02 5 4 4
nz New Zealand 4393500 10 15 2,28 3,41 4 3 5
se Sweden 9354462 20 36 2,14 3,85 3 6 6
lu Luxemburg 511840 1 1 1,95 1,95 8 5 7
de Germany 81802000 155 221 1,89 2,7 7 7 8
at Austria 8404252 15 25 1,78 2,97 6 8 9
ie Ireland 6197100 10 13 1,61 2,1 13 9 10
fr France 63136180 91 119 1,44 1,88 12 12 11
au Australia 22632213 31 57 1,37 2,52 9 10 12
be Belgium 11007020 15 17 1,36 1,54 10 11 13
uk United-Kingdom 62008048 67 106 1,08 1,71 14 14 14
nl Netherlands 16674600 18 37 1,08 2,22 11 13 15
dk Denmark 5564219 6 10 1,08 1,8 17 17 16
ca Canada 34480000 27 57 0,78 1,65 15 15 17
hr Croatia 4429078 3 3 0,68 0,68 20 18 18
es Spain 46030109 31 51 0,67 1,11 16 16 19
lt Lithuania 3225346 2 2 0,62 0,62 28 19 20
cz Czech Rep 10540748 6 6 0,57 0,57 21 20 21
it Italy 60605053 33 47 0,54 0,78 23 22 22
bg Bulgaria 7351254 4 4 0,54 0,54 25 23 23
il Israel 7602400 4 6 0,53 0,79 24 24 24
us USA 308745538 162 364 0,52 1,18 19 21 25
hu Hungary 9979000 5 11 0,5 1,1 18 25 26
lv Latvia 2245357 1 1 0,45 0,45 26 26 27
uy Uruguay 3494382 1 2 0,29 0,57 22 27 28
jp Japan 127960000 33 46 0,26 0,36 30 28 29
pl Poland 38186860 9 13 0,24 0,34 29 29 30
cr Costa Rica 4253897 1 1 0,24 0,24 31 30 31
pt Portugal 10647763 2 4 0,19 0,38 27 32 32
sk Slovakia 5429763 1 1 0,18 0,18 32 31 33
gr Greece 11305118 2 3 0,18 0,27 33 38 34
ar Argentina 40091359 7 9 0,17 0,22 34 33 35
tw Taiwan 23061689 3 3 0,13 0,13 37 34 36
br Brazil 190732694 20 21 0,1 0,11 36 35 37
by Belarus 9648533 1 1 0,1 0,1 35 36 38
mg Madagascar 20653556 2 2 0,1 0,1 44 37 39
cu Cuba 11239363 1 1 0,09 0,09
38 40
kr South Korea 48758000 4 6 0,08 0,12 39 39 41
ec Ecuador 14790608 1 1 0,07 0,07
40 42
cl Chile 17224200 1 2 0,06 0,12 42 41 43
ro Romania 21466174 1 2 0,05 0,09 45 43 44
co Colombia 45925397 2 3 0,04 0,07 41 44 45
ru Russia 142905200 6 7 0,04 0,05 43 42 46
za South Africa 49991300 2 9 0,04 0,18 38 48 47
my Malaysia 27565821 1 1 0,04 0,04

48
ve Venezuela 29105632 1 1 0,03 0,03 40 45 49
pe Peru 29496000 1 1 0,03 0,03 46 46 50
tr Turkey 73722988 2 2 0,03 0,03 47 47 51
mx Mexico 112322757 2 2 0,02 0,02 49 49 52
th Thailand 63878267 1 2 0,02 0,03 50 50 53
eg Egypt 80085862 1 3 0,01 0,04 51 51 54
in India 1210193422 8 8 0,01 0,01 52 52 55
cn China 1339724852 7 11 0,01 0,01 53 53 56
ua Ukraine 45888000 0 0 0 0 48 53 57























896 1450 61,79%



A few interesting facts:
  • Martinique pops up at rank 3. As this French overseas "d partement" has its own ISO code, it is counted here separately from France, though Martinique inhabitants are French citizens. That's of course a though case but I consider that David did choose to use "MQ" in his record, which means this is important for him. Let's respect that wish.
  • Norway is now ahead of New Zealand. One more DD since last count
  • Sweden is ahead of Luxembourg. Two more DDs wince last count
  • France takes over Australia and Belgium. *seven* more DDs since last count!
  • UK is ahead of Netherlands now. Three more DDs since last count.
  • Denmark passes Canada and Spain (50% more DDs for DK), while Croatia passes Spain (because Spain lost 3 DDs).
  • USA continues to go down (by 3 this time). We're constantly losing developers over there (-3 in one year).
  • And we have a new country in this list as Malaysia now has a Debian developer. Along with Martinique (ahem), this makes two new "countries" in this list. No country disappeared.
  • For the first time in 12 years, DebConf will be in a country (Bosnia and Herzegovina) that has NO Debian developer. This has to change.
  • We have 23 more active Debian developers and 40 more developers overall.

8 June 2011

Matt Zimmerman: DEX finishes first batch of derivative patches for Debian

It s been a few months since Zack and I announced the DEX project, which aims to improve the Debian ecosystem by working jointly with derivative distributions. Our first milestone The goal of our first project, nicknamed ancient-patches, was to clear out an old batch of a few hundred Ubuntu patches whose status was unclear. We couldn t tell which ones had been merged into Debian, which were waiting in the BTS, and which had yet to be submitted to Debian. All of them were several years old. I m pleased to announce that this project is now complete. Thanks to help from David Paleino, Colin Watson, Nathan Handler and Steve Langasek, we were able to clear over 95% of the patches in a matter of days. These were the easy ones: patches which were obsolete, or had already been applied. We discussed the remainder, and resolved all of the patches whose status was still unclear. This left the harder ones: patches stalled in the BTS, and patches where there was no consensus about what to do with them. One of the stalled patches was merged into Debian via an NMU, eliminating the delta between Debian and Ubuntu. Another had been submitted to Debian by a third party, but was no longer shipping in Ubuntu, so we considered it obsolete for purposes of this project. This has left only two patches out of the original list of 277. Both of them are filed in the BTS and have been discussed with the relevant maintainer team. One of them is expected to be obsoleted when a new upstream version is packaged, which implements similar functionality. The other is being discussed with the upstream developers, but there is no conclusion yet about whether it can be merged upstream or in Debian. Conclusions Although we weren t quite able to clear the whole list, we still consider the project to be a success because:
  • We ensured that all of the patches received due consideration for inclusion in Debian
  • We proved the concept of DEX, with developers from Debian and derivatives cooperating on a common goal and sharing tools
  • Most importantly, we learned from the experience
What s next In the most recent DEX update on debian-derivatives, I highlighted a few important events for DEX:
  • Our second major project, nicknamed big-merges , will begin soon. Our goal is to identify the few packages which are most diverged between Debian and Ubuntu, and work to get them as close to identical as possible. If you have suggestions for packages to focus on, let us know!
  • Allison Randal is beginning a DEX project to implement the Python 2.7 transition across Debian and Ubuntu
  • Nathan Handler is working on a Summer of Code project to develop specialized tools to help with this kind of cross-distribution teamwork
  • Zack is organizing a derivatives BoF at DebConf 11
We re looking forward to seeing DEX develop further. If you d like to get involved, come and join us on the debian-derivatives mailing list or IRC (#debian-derivatives on freenodeOFTC). Matt Zimmerman and Stefano Zacchiroli

1 June 2011

Tanguy Ortolo: Coding a new BitTorrent tracker?

The BitTorrent protocol works with trackers, that track the clients or peers that share a given file. This is one specific design of a peer-to-peer protocol, very appropriate for official distribution: for instance, Debian runs a tracker for distributing the installation images.The problem There exists many BitTorrent clients, but, for what I have seen, few BitTorrent tracker. Within Debian, I think the only trackers available are the original BitTorrent's one, and its fork BitTornado. Both suffer from serious drawbacks:
  • they have been unmaintained (upstream) for years;
  • they provide both a tracker and a client in the same package, whereas a BitTorrent client and a tracker do not have much in common, and most people are only interested in the client, so the package maintainer had to completely disable the tracker daemon, which complicates the task to get a working tracker;
  • the tracker's logging simply sucks: they had the brilliant idea to bufferize their log, with what seems no buffer control at all, so you get half-written lines, that get complete half an hour later, and so on.
Proposed solution Now that I have criticized a lot, let us be more constructive. All these issues could be fixed by modifying the code and the package (well, by adopting it, for the first one). I think it is not worth doing so, exactly because they implement both a client and a tracker: there are many good BitTorrent clients so there is no real need for them as clients, and because a tracker's job is quite different, and easier than a client's, it would be useless to maintain a client with the tracker. So, I am considering coding a BitTorrent tracker. Even though the tracker protocol is based on HTTP, it is completely stateful so it would be a standalone daemon rather than a CGI-style program. I would code it in Python because this is the language I currently prefer, and I may call it tbtt (the BitTorrent tracker, or Tanguy's BitTorrent tracker, or transport blind tout terrain (all terrain armoured transport)). If you have any information or suggestion, please comment! Perhaps I missed some existing tracker that would do the job instead of coding a new one?

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