report from GHM 2011 Debian and GNU have a lot in common: starting from the fact that strstr() applied to the respective project (full) names does not return NULL, up to the the common objective of building a UNIX-like operating system that grants fundamental software freedoms to its users. That is why I've been very pleased when the organizers of GNU Hackers Meeting 2011 (GHM) invited me to attend and speak about Debian and its relationships with GNU at the event. Slides of my talk are already available, while a video is being encoded (it will probably show up on both GHM homepage and IRILL website). Acknowledging the commonalities of goals on both Debian and GNU sides, we took the chance of this encounter to review how each project feel about relationships with the other (my original inquiries for the Debian community can be found on debian-project) and to talk it over during a discussion session scheduled to happen just after my talk. Yesterday, I've summarized all my notes from GHM 2011 in a report posted to debian-project. Quoting from there: After this experience, it is striking for me how much we have in common with GNU (ideally, culturally, socially, etc.) and at the same time how harsh can our "family battles" become at a times. Let's avoid that the remaining [few] differences get too much in the way [of collaboration], especially when that can be easily avoided. Enjoy!

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): 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:

• Set up the infrastructure for your project before GSoC: We transitioned from svn to git (on github) just before GSoC started. While it was a bit tough to work with git in the beginning it quickly payed off (patch reviewing and discussions on github were really much more easy). We did not have proper regression tests running daily during most of GSoC leaving a number of issues undetected for quite some time. Now that we have buildbots running I keep wondering how we could survive for so long without them :-)
• Even though all of our students worked very independently, you want to mentor them very closely in the beginning such that they write code that you like to see in your project, following coding style, utilizing already existing helper routines. We did this and it simplified our lives later - we could mostly accept patches as is.
• Expect contributions from external parties: We had contributions to shogun's ruby and csharp interfaces/examples. Ensure that you have some spare manpower to review such additional patches.
• Expect critical code review by your students and be open to restructure the code. As a long term contributer you probably no longer realize whether your class-design / code structure is hard to digest. Freshmans like GSoC students immediately will when they stumble upon inconsitencies. When they discover such issues, discuss with them how to resolve them and don't be afraid of doing even bigger changes in the early GSoC phase (not too big to hinder work of all of your students though). We had quite some structural improvent in shogun due to several suggestions by our students. Overall the project improved drastically - not just w.r.t. additions.
• As a mentor, work with your student on the project. Yes, get your hands dirty too. This way you are much more of an help to the student when things get stuck and it will be much easier for you to answer difficult questions.
• As a mentor, try to answer the questions your students have within a few hours. This keeps the students motivated and you excited that they are doing a great job.

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:

• Locally Linear Embedding
• Kernel Locally Linear Embedding
• Local Tangent Space Alignment
• Multidimensional scaling (with capability of landmark approximation)
• Isomap
• Hessian Locally Linear Embedding
• Laplacian Eigenmaps

See below for the some nice illustrations of dimension reduction/embedding techniques (click to enlarge). 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. 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

• Representing covariance matrices as their SVD
• Doing operations in log domain to avoid overflow/underflow
• Setting minimum variances to avoid singular Gaussians.
• Merging/splitting of Gaussians.

An illustrative example of estimating a one and two-dimensional Gaussian follows below. 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.

This is just a quick post to remind myself in the morning, as soon as I've made it I intend to turn my computer off and leave it off until I can re-organize my office. I've been using mutt for my email for the past few years. Nothing compares to the flexibility of procmail/sieve for organizing server-side mail, and then mutt is ideal for reading them. With the addition of the mutt-patched sidebar mode you can even go for a few days before realizing you're not in a graphical environment. But one thing I do long for is the ability to execute scripts at various times. Thus far I've not actually planned what I'd like to do, but as a starting point imagine being able to execute a hook when new mail arrives? Or when you send a message matching a pattern in some fashion? There are some things out there, such as the various hacks which are designed to abort sending a message if you mention "See attachment" in a message body but fail to add one before sendign the message. These hacks generally abuse the sendmail configuration such that they're extremely ad-hoc and hard to chain/nest. I've mellowed out over the years and I have no interest in attempting to write a mail-client (though at the same time how hard can it be? Just restrict yourself to using inotify on ~/Maildir and offload delivery to exim and you're almost done? I guess the hard part is the UI, though I do like the mutt + sidebar layout. Write the whole thing in some scripty language?) I'll re-examine notmuch and gnus over the next week or two, but I suspect both will continue to disappoint in various ways. Anyway, for the moment I'm just pondering. But threading is an obvious concern. Most current mutt hooks relate to the local folder, or the local message. If I were viewing a message in one directory and a new mail notification fired for a delivery to both ~/Maildir and ~/Maildir/.people.foo I'd need to either serialise them or thread them. Ponder ponder. In other news I've been doing more photography recently. Nothing cohesive except for my recent experiment with shooting a "street-girl" outdoors in falling light, but that was an interesting challenge and the results were sufficient to make me want to try shooting outdoors in an organized fashion again. (Some random images have been linked to from my wee twitter page.) ObFilm: "She doesn't get eaten by the eels at this time " - The Princess Bride

[UPDATE 2011-09-05]I received some questions (or saw them), which I tried to answer with a follow-up entry.[/UPDATE] As I tried to explain this a few times in the past to others and had trouble myself, when I started using Linux, I thought I take some time today and write down what parts comprise the Linux graphics stack and how they interact. I'll ignore some parts which aren't too interesting to an average user at the moment, to keep this post as consise as possible. Apart from that, I hope I'm able to put all the relevant data into one spot. Let us start our little journey in the kernel. There, in a directory named gpu you'll find the drm directory, which contains all DRM drivers. In this post, we'll focus on those. The drivers in that directory are the kernel side of the Direct Rendering Infrastructure (DRI) and are responsible for managing concurrent access to the graphics hardware. They also provide interfaces to pass commands and data to the GPU. The DRI wiki explains the three main purposes of the DRM modules. The DRM module is also the part that decides whether KMS or UMS is used. Other acronyms you might hear with regard to graphics acceleration on Linux and are referring to the Kernel part are:

• GEM: an Intel-developed memory management system for GPUs.
• TTM: refers to the memory management system used by almost all non-Intel drivers (e.g. AMD's Radeon drivers). The TTM interface is "GEM-ified", meaning it offers the same API as GEM.

Apart from that, every driver has its hardware-specific parts like utilizing power-saving functions of the respective GPUs, loading firmware, if required, etc. Now we move from Kernel space to user land. We'll ignore any non-X and non-Mesa parts (like acceleration for TTYs). That means, that our next GPU specific part is most likely the DDX. (Please note, that the classic DDX might be replaced by a Gallium3D state tracker, currently that would be the xorg state tracker, but xorg will be replaced by XA. This is only an option if the Gallium driver for your GPU supports one of those state trackers, see the Gallium status page for further details.) The DDX for your GPU offers plain (2D) X acceleration on your hardware. The respective DDX' are generally named xf86-video-[NAME], where [NAME] is replaced by e.g. ati or intel. The DDX decides which X acceleration paths are available. Acronyms you might hear, referring to the DDX part of the graphics stack, are:

• EXA: even though it looks like an acronym, the X.Org wiki Glossary defines it as:

  acceleration architecture with no well-defined acronym

  EXA superseded the older XAA and offers 2D acceleration, often in conjunction with XRender.
• UXA: more or less EXA for Intel GPUs.
• GLX: actually not a part of the DDX, but an extension for X. It provides a way to draw with OpenGL into an window managed by X.
• XRandR: An extension for X which needs to be supported by the DDX to work. It offers a standardized way to set up (multiple) heads (e.g. resolution, position, rotation, etc.).

We're almost through: the last important part is the 3D acceleration offered by a Mesa driver. Mesa drivers come in two flavours: classic (e.g. all Intel drivers which are supported by Intel) and Gallium3D-based (like the drivers for Radeon chips from the R300 onwards). The difference here is, that the Gallium3D drivers try to share as much code as possible (and thus simplify writing a new driver supporting many platforms, systems and technologies), while the classic drivers are specific to certain platforms, chips, and technologies. They share much less code among each other. All parts of Mesa need direct access to the graphics hardware (DRI) The Mesa drivers use the 3D pipeline of the GPUs for accelerated drawing, even for non-3D applications like video acceleration (recently VDPAU, XvMC and VA support were added to Gallium3D, driver support followed quickly). Otherwise the Mesa drivers are mainly used for OpenGL acceleration. Users of OpenGL include scientific programs, CAD and of course games. This concludes our little journey through the various parts of the Linux graphics stack. I hope it helps in understanding the building blocks.

As written about here earlier, cats have a nice life. I walked into my home seeing three cats in a row, all black: two lazing around, the third (with white spots, and belonging to a different neighbour from the other two) ambulating. I went up and got my PocketPC with the already mentioned camera application to take a shoot. Sadly, the more shy cat went away, but I got some pictures of the other two here they are, internet photo stars follow the hyperlink to get a large version. Later I came back from geocaching (2 GC.COM-only, 1 OC-only *yay!* found, one not found due to not taking any hardware with me) the bigger guy lazed around in the bush next to where I usually park my bike. Lucky

I often hear criticism of "negative campaigning" in the free software movement. For example, in reply to a blog post I once wrote about an FSF campaign, several people argued against, "negative campaigning of any sort, in any realm." Drawing an analogy to political smear campaigns, some members of the free software community have taken the position that negative campaigning in general is not useful and that negativity has no place in our advocacy. First, it is important to be clear on what we mean by a negative campaigns. I believe that there is a fundamental difference between speaking out against policies or actions and smear campaigns that employ untrue claims, ad hominem attacks, and that attempt to avoid a real conversation about issues. I will categorically condemn the latter form of smear campaigning in campaigns for software freedom or for anything else. That said, negativity directed at negativity has had a positive effect in many social movements. I have supported and participated in "negative" campaigns against proprietary software, software patents, DRM, centralized network services, and the firms behind these practices. I've done so because I believe that if one is taking an ethical position, it is justified, and often necessary, to not only speak about the benefits of freedom but against acts of dispossession and disenfranchisement. In some of the most effective social movements, unambiguously negative messages have been central. Should a campaign for abolishing child labor talk only about how valuable adult workers are to their employers or how happy kids are when they don't work? Should a campaign trying to abolish land mines talk only about the benefits of bomb-free fields and intact lower limbs? Should a free speech organization only speak out about the social welfare brought by a free press and never against acts of censorship? These may seem like outlandish comparisons but you can find people writing, only a couple centuries ago, about how slavery should be abolished by arguing in favor of the benefits of paid labor. Even if the economic arguments in favor of paid work are strong, these arguments seems irrelevant and offensive today. Whether slavery is more or less efficient is a moot point. Society has rejected it because it is wrong. We have made important strides toward eliminating injustices like child labor and slavery because activists waged decidedly negative campaigns against them and convinced others to join in opposition. In doing so, activists declared the status quo unconscionable and created an ethical responsibility to find alternatives and to redefine what was "realistic." While I will not suggest that the movement for software freedom is comparable in ethical weight to these other causes, I know that the free software mission is similar in kind. Of course, if one does not think that user control over technology is an ethical issue but is instead merely a matter of choice, one will probably oppose negative campaigns. It is also possible that a particular negative campaign is tactically unwise in that it is unlikely to reach a large audience, unlikely to change people's minds, or be difficult to carry out successfully. But such campaigns are a bad idea because they are ineffective, not because they are negative. Additionally, a movement that is purely negative and offers no reasonable alternative to the stated ill may also be unlikely to succeed. This is why, for example, I believe it is good that the FSF uses the large majority of its resources in the "positive" role of supporting free software. For those that do treat technological empowerment as an ethical ideal, it is both justified and essential to condemn the systematic disempowerment of others through non-free software just as we celebrate the benefits of software freedom. "Negative" campaigns against proprietary software, software patents, and DRM in music have already led our community to important -- if incomplete -- victories. The desire to right wrongs has been a critical part of our movement's success and of many others'. We would be wise not to give it up.

Several modern complex file formats are based on a ZIP container: this is at least the case of OpenDocument and EPUB. However, they are not simply a bunch of files joined into an archive, but they follow some rules in order to be easily recognized by tools such as file. As I had to unpack, modify and repack such a container, here is a recipe to do that.The zip command is flexible enough to allow you to work in place (I am not sure that it is really in place) to add, remove and replace files in the archive, however I find it more convenient to work on the unpacked tree and repack later. Unpack and work To unpack, just unzip, being aware that these containers do not have a root directory, so it is better to extract them to a dedicated directory. Modify as you wish; if you add, remove or replace files, remember that there is a file list to modify accordingly: META-INF/manifest.xml for OpenDocument, OEBPS/content.opf and possibly OEBPS/toc.ncx for EPUB. Repack To repack, you must create a ZIP archive without extra file attributes, and put the file mimetype uncompressed in first position. Its goal is to be visible as plain text at a fixed position, to serve as a magic file type indication. The remaining files can be stored compressed and in random order. For an EPUB, for instance, this gives the following commands:

% zip --no-extra --compression-method store ../book.epub mimetype
% zip --recurse-paths ../book.epub META-INF OEBPS

This could be automated by a dedicated script, but I felt no need to write one yet. By the way, these options can be abbreviated as -X0 and -r.

(Photo credit: Obey Arthur Liu; originally on Picasa, license.) Three weekends ago, I participated in a Debian bug squashing party. It was more fun than I had guessed! The event worked: we squashed bugs. Geoffrey Thomas (geofft) organized it as an event for MIT's student computing group, SIPB. In this post, I'll review the good parts and the bad. I'll conclude with beaming photos of my two mentees and talk about the bugs they fixed. So, the good:

• Attendance. As Luke put it, when he arrived, there was hardly anyone there. Then people showed up! And then mentorship and pedagogy happened! In all, 14 people attended, seven of whom are active in Debian or its derivatives (Ubuntu, Debathena).
• We took photos. Arthur took a wide panoramic photo, and I snapped a few good ones, too. (Thanks to Jessica McKellar for letting me borrow her camera.) Here's my full photo set.
• Good, free pizza. Props to geofft for ordering from Beauty's, and props to SIPB for picking up the tab.
• We fixed bugs! I mentored two new Debian contributors through their first release-critical bug fix. Both of them said they would attend similar events in the future. One of my mentees is now idling and asking questions in the #debian-mentors IRC channel.
• The Debian Events team republished the event. MadameZou posted the event to debian.org, giving it a nice stable URL.
• geofft made a good list of bugs to work on. He worked from the release-critical bug list, categorized the bugs by expected difficulty, and made somee short notes about how to fix the bug. This turned out quite useful.
• People printed music to the speakers. If this sounds weird, you should read the SIPB documentation for how to use Gutenbach (written by Liz Denys).
• We had a good ratio of developers to newcomers. This was hugely helpful; from what I saw, new people rarely waited very long for their questions to be answered. Thanks to Luke Faraone, Sam Hartman, Obey Arthur Liu, Karl Ramm, and Christine Spang from Debian, and Geoffrey Thomas from Debathena, for sharing knowledge.

The event was a success, but as always, there are some things that could have gone more smoothly. Here's that list:

• We hadn't prepared for people to do Debian development on Ubuntu. In particular, it took Luke and me about half an hour to come up with a pbuilder command line that worked.
• We didn't contribute to Ubuntu, just Debian. I actually think this is fine, but geofft did originally want people to work on both. He was disappointed, and we could have managed to do that if we had done more prep.
• We could have reached more prospective attendees. I know earlier in the year, daf organized a highly popular Debian packaging tutorial elsewhere on campus. I didn't see any of those people at the event, and I think some would have attended if they had known about it.
• Some people wanted a bit more context. In particular, attendees asked me about what makes a bug release-critical and what it means to do a non-maintainer upload. We could have taken some time to explain these to the whole group; instead, we dove right into hacking. Because we had so many mentors, I think people did get their questions answered, but we can't sustain that if the event grows in size.
• Mentees didn't always get high-quality help. geofft suggested Jessica work on one bug, and when she had a question, she asked Luke Faraone. Luke wasn't familiar with the bug, and he skimmed it, not realizing that the bug changed issues midway through the bug log. As a result, his initial help was unhelpful. After Luke, Jessica, and the bug were on the same page (so to speak), Jessica received clear, sound answers to questions.

Still, it turned out well! I did three NMUs, corresponding to three patches submitted for release-critical bugs by my two mentees. Those mentees were: Jessica McKellar is a software engineer at Ksplice Oracle and a recent graduate of MIT's EECS program. She solved three release-critical bugs. This was her first direct contribution to Debian. In particular:

• #636201: While updating the package for multiarch support, the maintainer of wildmidi presumably made a typo. A single character was missing from a "Replaces:" declaration in debian/control. This bug caused upgrades to fail. Sam Hartman uploaded an NMU based on a patch Jessica prepared.
• #626420: The scribus-doc package failed to build from source due to a missing build-depends entry. This one was super easy, and served as a good test package for setting up and using pbuilder.
• #565000: The switch to gcc-4.5 left hubbub unable to build from source due to new GCC warnings that made -Wall fail on the source, although it would succeed with earlier versions of the package. This led to long philosophical discussions about the particularly most reasonable fix: removing -Wall, or adding a more specific exception.

Jessica has since gotten involved in the Twisted project's personal package archive. Toward the end of the sprint, she explained, "I like fixing bugs. I will totally come to the next bug squashing party." Noah Swartz is a recent graduate of Case Western Reserve University where he studied Mathematics and played Magic. He is an intern at the MIT Media Lab where he contributes to DoppelLab in Joe Paradiso's Responsive Environments group. This was definitely his first direct contribution to Debian. It was also one of the most intense command-line experiences he has had so far. Noah wasn't originally planning to come, but we were having lunch together before the hackathon, and I convinced him to join us. Noah fixed #625177, a fails-to-build-from-source (FTBFS) bug in nslint. The problem was that "-Wl" was instead written in all lowercase in the debian/rules file, as "-wl". Noah fixed that, making sure the package properly built in pbuilder, and then spent some quality time with lintian figuring out the right way to write a debian/changelog. That's a wrap! We'll hopefully have one again in a few months, and before that, I hope to write up a guide so that we run things even more smoothly next time.

Hello planet Mozilla. For my first post appearing in the planet I d like to write about a recent community aspect I experienced, the rest will probably be more technical. While we have some great volunteers participating in Mozilla, there s aren t any Mozilla representatives in Israel. To be exact, there are a few Israeli that do work for Mozilla (and I think they work from within Israel), but we don t feel them in the local free software community. I was very surprised to see 5 people from Mozilla attending Wikimania 2011, but this is of course a good surprise. I would have excepted to see representatives in a free software conference, but we still haven t had any international free software conference in Israel (maybe some day I could bring Debconf here). A week later I had another representative arriving for a free software conference I organized called August Penguin. This is the first time having someone arriving from abroad just for the local conference. For me, a free software user and contributor, Mozilla is mostly a software project. Meeting the various representatives gave me the chance to know some of the other sides of the organization and its activities. For me that was really interesting and I think that it would be positive to do many of the activities also in Israel. Besides the interest in the organization, I had the chance to host some of the representatives by showing them around, providing a place to crash at and making sure they stay after the conferences would be as easy and enjoyable as possible. Reflecting back, my place would probably could be the Moziila Inn as I had 3 people from Mozilla as guests in one week (on separate days). For me that was fulfilling the community side of the term free software community , as we re not only a technical community. Others might even call this an outreach program (a term I heard from all 3 guess in various contexts), but I m still not sure who is outreaching to whom (: So if you happen to work on Mozilla stuff, and arriving Israel, drop me a note
Filed under: Israeli Community, Mozilla

Oogoo and Raspberry Pi While I haven't been doing much blogable myself, I have recently found a couple of interesting things via Hack A Day: Oogoo is a moldable silicone clay that is easy to make from readily available substances. The main problem for what I'm thinking of using it for is it releases acid as it cures, so I'm not sure using it to encapsulate metal is a good idea. Still, it looks like something fun to work with. Raspberry Pi while not shipping yet (they hope for November/December) looks very interesting -- a $35 (or $25 for the less well configured one) low-power credit-card sized Arm board running Linux with a reasonable amount of I/O (USB, Ethernet, HDMI, I2C, I2S, SPI, serial, audio, composite video, and GPIO). The alpha version is running Debian, but they plan on shipping with Ubuntu or another distro. While the first version is aimed at experimenters (no case, no power supply) they are a UK non-profit aiming at the education market. This is not a direct competitor with the OLPC, which is aimed at younger children.

I stopped my story in early 1994, after my Big Switch to the mysterious and new world of Linux. My home server, kheops, is now running Debian and is fed with news and mail by FrMug, formerly French Minix Users Group and now run by AFAU, the "Association Fran aise des Amateurs de Usenet". As I'm still console-challenged, I'm reading mail and news on another machine I have at home, named "khephren", which is running an, ahem, beta copy of Microsoft Windows 95. Yeah, I know...:-) These 1994-1999 years were mostly the Usenet years, for me. I gradually became more and more involved in several fr.* newsgroups, either related to the Linux world...or to the Windows world. The latter was professionnally a bonus for me as 1994 is also the year where I switched from the Material Science department at Onera to the Network and Computing Department. My mission there was to accompany the increasing prevalence of personal desktop workstations in the daily life of what was formerly the Big Castle of Computing at Onera, hosting various generations of Cray computers, most of which being in the Top500 world supercomputers (we even had one in the Top10, very briefly, at somepoint). So, I was "the PC and Windows guy" in this world of supercomputing, Unix and network wizards. But my hobby at home helped me keeping and growing skills in both "worlds" which, over the years, has proven to be a not so common profile..:-) Meanwhile, at home, I was spending hours and nights reading those newsgroups...or getting involved in fr.* hierarchy management..or expanding my friends network to many people in the news, Linux, BSD worlds. That lasted for about 3 years with ups and downs (with three young kids at home, you end up having slightly less time...). I was gradually improving my home server use, adding more functionalities to it, for instance setting it up as a file and print server with Samba 1.9.something (this will be the beginning of a long story with samba!). Unfortunately, my dear Ren had passed in the meantime. Ren did so much for Linux in France that he'll be the only link I give in this article. If you happen to go through P re Lachaise cemetery in Paris, go to its Memory garden instead of visiting Jim Morrison's grave and drink a whisky bottle in memory of Ren . Or just install one of the most funnily named Debian packages: le-dico-de-rene-cougnenc and, again, drink something to his memory (whisky is highly preferred). We then reached 1997 and a specific event: my father (who was very sick for years) passed during summer, some time after my grand-father passed too. As it apparently happens for many people, it triggerred me into the interest for family history. After all, those people who are going away are family memories. And, in some way, I wanted to keep track of this memory. As a consequence, I started collecting family memories, interviewing my close relatives (the oldest ones) and ending, of course, in tracking all this with my computers. That was the start of a long genealogy research that sent me on the track of the Perrier family (of course), but also all other branches, on my mother and father side, as well as reconstructing the tree of cousins we have, etc, etc. As anybody who did that knows, this is quite an endless task but I went very committed to it. I quickly ended up in joining research groups that were using the recent growth of personal access to Internet communication. Those groups were, in these 90's, building elaborated systems where people can help together in their research instead of having to travel to places where archives are stored. I participated to many such groups and even ended up animating one who was doing research in archives of the "Yvelines" "d partement", my place of living (even though I have no family branch there). At the same time, other groups were sending me research results for my own family in the French region where my roots are. Collective effort, help others for free, you can recognize things that are a constant all over these years, indeed. It actually helped me in tracking my Perrier ancestors up to about 1680, with 11 generations of men holding that name (from Jean-Baptiste, my son, up to tienne Perrier, who is born about 1640-1650, in the small village named Briant in Sa ne et Loire, in France). Or even climbing up to Laurent Polette, born circa 1510, mentioned in a document date February 1562. He his my oldest known ancestor.Those folks being 15 generations before me. My oldest ancestor is born under Fran ois the First, King of France, protector of Leonardo Da Vinci, at the time La Joconde was painted or the Chambord castle was built. Doh. Unfortunately, genealogy software, at that time, was quite poor for Unix systems. Lifelines was a quite strong development but wasn't that user-friendly and I ended up using a Windows-based "shareware" software written by an individual. Still, my Linux machine was used quite intensively: databases were stored there, and saved there, all important informations were there, my mail was received there, along with dozens of mailing lists I was reading. I even hosted a few mailing lists on my home server. Still, in the meantime also, again in 1997, in October, another event happened. We had a pollution peak in Paris area and October 1st was the first (and as of now the only ever) day where driving restrictions were applied. Up to that moment, I was driving to/from work (30 kilometers one way). I decided to use this opportunity to really test public transport, for one full month. As I knew it would take me much more time than driving, I tried to imagine a way to use that time. How about reading mail and news on a laptop instead of only at home? Done... In a few days, I found a used Compaq Aero laptop (486 16MHz), I installed Debian "bo" on it, switched my mail and news workflow to console programs (mutt and slrn) and here we go! So, finally, in October 1997, I was using Linux nearly all time long, the only exception being genealogy data handling. That laptop was named "mykerinos" (the small pyramid) and....my laptop is still named mykerinos, though it's now the 5th mykerinos I have..:-) Ah, and since then, I nearly always use public transport to go to/from work. Debian addiction is good for the planet! At some point (I don't remember exactly when...about 1999, I think), DSL connections appeared and one of the first DSL FAI emerged on France: Free. I was already using their services for dialup access, but DSL was then a revolution: persistent connection! And nearly immediately, static IP! I became one of their first DSL customers (and I'm still one). Moreover, I had then friends working there...and they had many Debian machines to host their services. So, with the help of my Freenix friends, some DNS hosting on their machines and the still tireless eu.org entirely free domain, perrier.eu.org was born. Immediately, this gave me opportunities for doing many interesting things with my home server: setting up www.perrier.eu.org and use it....for learning web things and sharing genealogical data. For instance, I ended up hosting some data sent by other genealogists such as digital copies of archives for some French regions, all served through my 512/128kbps DSL line (quickly upgraded to 2Mb, IIRC). And, very quickly, I felt the need to share my family tree, of course! And here comes Geneweb. Written (in Ocaml) by Daniel de Rauglaudre, Geneweb was (and still is) by far one of the best tools to share genealogy data over the Net. So, I ended up installing it on my home machine. Guess how I did that? "apt-get install geneweb", of course. Yes, it was packaged. Indeed by Brent Fulgham who did the initial release on July 22nd 2000. Here, my memory is a little bit vague. I think I actually packaged Geneweb for my own use and sharing it on upstream FTP site, forking Brent's package as a start, but updating to latest upstream release. Then I quickly ended up having discussions with Brent about this new upstream release, and that lead to:

geneweb (3.10-3) unstable; urgency=low
  * Merging with unofficial package from Geneweb ftp site
    (in preparation of new maintainer [Christian Perrier] takeing
    over responsibility).  Note that all of this work is from
    Christian.
  * Default database dir is now writable by members of geneweb group
  * New geneweb group added at installation
  * Package tries to properly handle former installations of the
    unofficial Geneweb package available on Geneweb ftp site
  * Debconf dialogs translated in french
  * More languages available
  * Creation of /var/geneweb/etc, /var/geneweb/cnt, /var/geneweb/images
    with proper permission so that authorised users may use these also
  * When de-installed, all databases are exported with gwu (should allow
    smooth upgrades when the databse format changes)
 -- Brent A. Fulgham <bfulgham>  Mon, 22 Jan 2001 19:30:47 -0800

See? Already "debconf translation to French"! "More languages available". Here we are. As discussed with Brent, he propsoed me to take the package over. So, on January 11th 2001, I had applied in the New Maintainer Process. I'm amazed how quickly it went indeed: there was a tool I needed, it needed to be packaged, I could handle the packaging...and then I decided to be involved. Here we are: bubulle is on his way to become one of those magicians who are building the best universal operating system. Yes, me, the clueless material scientist..:-) How did it go? You'll know this in next episode, of course...

Dear Lazyweb, since KDE4 is in unstable, the taskbar behaves very annoyingly when working with two monitors with different resolutions. I have a laptop. When I m at work, I put it into a docking station which is connected to a huge monitor. I m not working with dualhead or something, I m just using the huge monitor at work and the laptop s screen at home. I always want the taskbar to be maximized. The problem is, that KDE s taskbar fails to adjust the size of the taskbar correctly: Starting KDE at work, the taskbar is always too small (as wide as the laptop s monitor) and my first task is to maximize the taskbar. Starting KDE when I m back home, the taskbar is too wide (as wide as the external monitor s size) for the smaller monitor and I have to (ironically) maximize it again to fit on the now smaller monitor. Note that I m not using suspend or something. I m booting the laptop with the big screen connected or not. I also had that problem with KDE3, but that was fixed upstream long time ago. Has anyone a solution how to avoid this problem?

I ve sort of wanted a weather station for a long time. Lately, the ham radio hobby has intensified that, and I finally got one. When I finally got the serial link cable yesterday, well I was perhaps irrationally excited. Terah accused me of running all around the house while gathering up stuff for it. That probably wasn t too inaccurate. Anyhow, here s the sensor suite. The station is a Davis Vantage Vue, and they have pictures of the included receiving console on their site. On the upper left is the anemometer (wind speed sensor). Next to that is the rain collector for the rain sensor. There is a solar panel on the front for power, and underneath that is the wind direction sensor. The white thing underneath the back is the temperature and humidity sensor, which is inside a radiation shield. There is also a barometer in there someplace. The indoor console receives the data via a 900MHz wireless link. The console can also be connected via a serial, USB, or Ethernet link to a PC. All sorts of software can then do all sorts of things with it. The console itself, though, keeps a history, has hi/low reports, graphs, and current condition display that is quite useful already. But if course I d want it hooked up to a computer. I figured I couldn t put the console in the basement next to the server due to wireless signal strength issues, but also didn t want to require my desktop PC to be up for this to work. So I ordered the serial version, and some cheap DB9 to RJ45 adapter jacks. I have CAT6 strung throughout the house, so I simply converted a surplus Ethernet port to a serial port and it worked beautifully. There are a ton of weather-related programs out there. My requirements said that I wanted something that runs on Linux. Options there include wview, vanprod, RRD Weather Graphs, Weewx, Meteo, and the commercial non-free Weather Display. That s quite a few choices. Of those, wview had the best support for various devices from various manufacturers, which I figure might be important down the road. It can directly generate detailed weather webpages. It can also submit data to Weather Underground. Weather Underground has a feature called rapid fire which lets viewers screens update with current observations every few seconds. None of the noncommercial programs supported it, so I added it to wview. With my tree, it s now sending Rapid Fire updates. It also can submit data to the Citizen Weather Observer Program, which provides a way to both share it with others and provide it to forecasters at the National Weather Service and university researchers. It gets processed by their ingest system and is quality checked against their computerized QC metrics. Jacob has enjoyed this he got into assembling it, and often wants to go see if the anemometer is spinning. And I was surprised to kind of enjoy working with C again. Perhaps that was because I didn t have to touch malloc() even once?

User BobH asked on StackOverflow about accelerating path-dependent loops. He provided a simple example in which a vector gets filled conditional on the value of the preceding element. Simple to code, but hard to vectorise. By the time I saw that question yesterday evening, Josh Ulrich had already posted a nice answer suggesting to switch from ifelse to if to escape the overhead of a vectorised expression on simple scalars. I meekly added a comment suggesting that Rcpp would likely do well on this and that someone should volunteer such an answer. Well, it is still August and Mr. Someone is on holiday, so this morning I followed up with such an answer. And as it turns out to work quite well indeed, we will repost it here. Let's start with the general setup, and the two functions supplied by Josh. We also byte-compile these using the compiler package which is the culmination of several years of work by R core member Luke Tierney. This package was added to R during the last major release, and we assessed it in this earlier blog post as well as several Rcpp-related follow-ups. We also load the packages for on-the-fly 'inline' compilation and easy benchmarking:

library(inline)
library(rbenchmark)
library(compiler)
fun1 <- function(z)  
  for(i in 2:NROW(z))  
    z[i] <- ifelse(z[i-1]==1, 1, 0)
   
  z
 
fun1c <- cmpfun(fun1)
fun2 <- function(z)  
  for(i in 2:NROW(z))  
    z[i] <- if(z[i-1]==1) 1 else 0
   
  z
 
fun2c <- cmpfun(fun2)

We see that basic worker just assign to the i-th element based on the preceding element. Function two uses the aforementioned if statement, and both are also byte-compiled. Writing the same code in C++ using both Rcpp (for the R/C++ integration) and inline for the on-the-fly compilation, linking and loading of C++ code into R is pretty straightforward too:

funRcpp <- cxxfunction(signature(zs="numeric"), plugin="Rcpp", body="
  Rcpp::NumericVector z = Rcpp::NumericVector(zs);
  int n = z.size();
  for (int i=1; i<n; i++)  
    z[i] = (z[i-1]==1.0 ? 1.0 : 0.0);
   
  return(z);
")

This single R function call takes the code embedded in the argument to the body variable, builds a complete function in temporary file, and then compiles, links and loads it. We can now call funRcpp() just like the other four functions and do so via the benchmark() function of the rbenchmark package.

R> z <- rep(c(1,1,0,0,0,0), 100)
R> identical(fun1(z),fun2(z),fun1c(z),fun2c(z),funRcpp(z))
[1] TRUE
R> 
R> res <- benchmark(fun1(z), fun2(z),
+                  fun1c(z), fun2c(z),
+                  funRcpp(z),
+                  columns=c("test", "replications", "elapsed", "relative", "user.self", "sys.self"),
+                  order="relative",
+                  replications=1000)
R> print(res)
        test replications elapsed relative user.self sys.self
5 funRcpp(z)         1000   0.005      1.0      0.01        0
4   fun2c(z)         1000   0.482     96.4      0.48        0
2    fun2(z)         1000   1.989    397.8      1.98        0
3   fun1c(z)         1000  11.365   2273.0     11.37        0
1    fun1(z)         1000  13.210   2642.0     13.21        0

We can focus on the columns labelled elapsed and relative. The C++ version is faster by a factor of almost one-hundred compared to the byte-compiled version of funtion2, and almost four-hundred times faster than the plain-R variant of function2. And function1 is even worse, coming at well over twenty-two-hundred times the run-time of the C++ version. Byte-compilation also helps little here. For comparison, we also ran the original example of a very short vector, called more frequently:

R> z <- c(1,1,0,0,0,0)
R> res2 <- benchmark(fun1(z), fun2(z),
+                  fun1c(z), fun2c(z),
+                  funRcpp(z),
+                  columns=c("test", "replications", "elapsed", "relative", "user.self", "sys.self"),
+                  order="relative",
+                  replications=10000)
R> print(res2)
        test replications elapsed relative user.self sys.self
5 funRcpp(z)        10000   0.047  1.00000      0.04        0
4   fun2c(z)        10000   0.134  2.85106      0.13        0
2    fun2(z)        10000   0.328  6.97872      0.32        0
3   fun1c(z)        10000   1.080 22.97872      1.08        0
1    fun1(z)        10000   1.243 26.44681      1.24        0

The qualitative ranking is unchanged: the Rcpp version dominates. Function2 using if instead of the vectorised ifelse is second-best with the byte-compiled version being about twice as fast that the plain R variant, but still almost three times slower than the C++ version. And the relative differences are less pronounced: relatively speaking, the function call overhead matters less here and the actual looping matters more: C++ gets a bigger advantage on the actual loop operations in the longer vectors. That it is an important result as it suggests that on more real-life sized data, the compiled version may reap a larger benefit. All in all a nice demonstration of Rcpp, and a gain of almost one-hundred to the best byte-compiled version is nothing to sneeze at---especially when it is so easy to write and load a five-line C++ function thanks to Rcpp. Before closing, a quick reminder that I will giving two classes on Rcpp in a few weeks. These will be in New York on September 24, and San Franciso on October 8, see this blog post as well as this page at Revolution Analytics (who are a co-organiser of the classes) for details and registration information.

If someone in Germany (or want to send it to Germany [at low costs]) still has (new) Touchpads to sell, I d buy one or two of them at the reduced price (16GB: 99 , 32GB: 129 ), or take them for free. I promise that I will not sell them to others. I m interested in WebOS, in running Debian and/or Ubuntu on those devices (for the extra fun factor), and lend it to family members for surfing, etc. I also take other tablets and smart phones and various kinds of ARM and PowerPC hardware (I guess that s all that s interesting for me) for free, just send me an email if you have some and want to give them to me. This applies to Intel stuff as well, I d really like to get some kind of WeTab/ExoPC, but can t buy one currently (and they re probably to outdated hardware-wise for buying to make sense).
Filed under: Uncategorized

This is my fifth and final report about dextools for the 2011 Google Summer of Code program. During the summer, I worked with Matt Zimmerman and Stefano Zacchiroli to create a replacement web dashboard for the Debian Derivatives Exchange (DEX). The dashboard displays a list of projects and their respective tasks and then allows users to easily update the status of these tasks. The dashboard also contains two graphs for tracking the progress of projects and providing instant recognition of all contributions to a project. At the start of the summer, I knew that I wanted to to work on improving the DEX infrastructure. I had worked with the team on the ancient-merges project, and while a lot of good work was accomplished, the process for tracking our progress was a bit clunky and difficult to interact with. Anyone who read my initial proposal for the Summer of Code would probably agree that it was quite vague. I really did not have a solid plan for what I wanted to accomplish. This began to change after my initial phone call with my mentor, Matt Zimmerman. We decided that the first thing I would work on would be a basic dashboard. Our plan was to have all of the data stored on the Debian BTS. This would allow Debian Maintainers to benefit from DEX without needing to learn about DEX s tools and workflows. The dashboard would support multiple derivatives and multiple projects for each derivative. Each project would be made up of a list of tasks, where each task is linked to a BTS bug. I prepared a mockup and some initial code based on that plan. The dashboard was able to successfully display a list of BTS bugs and their information. It generated the lists by assuming that bugs would be usertagged with a user of debian-derivatives@lists.debian.org and a tag in the format of dex
. At this point, we started trying to make sure that the dashboard would work for things like the ancient-patches, python2.7, and the upcoming large-merges projects. It did not take long to determine that it would not work for all of these things. The ancient-patches project started with a simple list of patch names. While most of these patches eventually ended up as bugs on the BTS, they did not start this way. The dashboard would need to support specifying a list of task names. This meant that it would also need to store data itself and that not all data could be located on the BTS. This is when we first started to define what a task is. The dashboard tracks tasks. It does not directly track bugs or patches. A task is nothing more than a title and status with an optional assignee, note, and bug. This made it simple to convert a list of patch names or a list of bug numbers to a list of tasks. During the early early stages of the project, the dashboard moved around a lot. We hoped to have it end up on dex.alioth.debian.org, but we were not sure whether Alioth would meet all of our needs. This was right around the time of the Alioth migration. Thanks to some tips, I figured out that I could use a simple cronjob on wagner to pull the git repository for vasks. This would allow the running instance of the dashboard to always be up-to-date. The Alioth admins have also been quite supportive. They have installed several additional packages for me that were necessary to keep the dashboard running. From the start, Matt felt it was important to have some public documentation about the project. This would allow us to point people to something other than my blog posts. I decided to put this information on the wiki. At one point, I also had a copy of the wiki page stored in the git repository. This file was updated via a cronjob, and I then committed and pushed it when I had code changes. I ultimately decided that the best approach would be to maintain the page on the wiki. A basic README file is included in the git repository that simply links to the wiki page. On wagner, I have a cronjob running to pull a copy of the wiki page so that it can be accessed via the web. Since Matt was traveling/moving this Summer, he arranged for Stefano Zacchiroli to fill in for him as my mentor temporarily. It was at this point in the summer that I began working on the first graph script. The goal was to have a script to parse the list of tasks and generate a graph showing the number of open tasks versus time. This would allow us to easily track our progress, estimate when a project will be complete, and detect periods of slowing down. We decided that while we liked the Ubuntu burndown charts, they were a bit more complex than we needed, so we did not reuse their code. A dashboard that can t be modified is not that useful. An early goal of this project was to allow users to update the dashboard via the web. This proved to be a bit more difficult than I initially thought. First, all of the html files that make up the dashboard are generated by a script. This means that if you modify one of the html files directly, all changes will be lost the next time the script runs. When you make a change on a web form and hit submit, you usually expect to see the changes the next time you visit the page. In order to accomplish this, I made the form processing script directly modify the html files. However, at this point, we did not have a way to locally store extended information about tasks, causing the python script to delete all changes made via the web form. This issue was rectified fairly quickly. There is now a changes file that stores all information submitted via the web form. The python script reads this file and applies the changes when it is generating the html files. A second problem concerned the text inputs that were being used in most of the cells on the table. By default, some fields would have text cut-off if the string was too long. Text inputs have a size attribute that is meant to specify the number of visible characters. I attempted to set this attribute in a script to the length of the input s value. Strangely, the inputs ended up with a lot of extra whitespace following the text. This resulted in the table being stretched horizontally. After many hours of research and testing, I was unable to find a solution to this problem. We ultimately decided to simply remove the size attribute and accept that text will be cut-off. My code got some early testing from Allison Randal and other people working on the dex-ubuntu-python2.7 project. They were a huge help in providing feedback and finding bugs in the code. While the dashboard was unable to meet all of their needs (due to being in the early stages of development), I hope that it at least helped to make it easier to track the project s status. Whenever a script is accepting input from a user, it is important to validate it. Although the dashboard uses a select box to limit the choices for the status , it is still trivial to submit an arbitrary status for a task. That is why I added some validation to the form processing script. It will ignore any unknown values, ensuring that all tasks have a valid status. The other fields are a bit more tricky. They were designed to be arbitrary text fields. As a result, almost anything can be entered. There is no way to tell if something is a title or a person. We thought of a few ways we could change this, but most of them involved locking down the dashboard and restricting changes. The old dashboard treated the fields as arbitrary text, so we decided to not include any validation in the new one. One popular feature request was the ability to link directly to a project. Early versions of the dashboard had one main dex.html page that used javascript to pull in the various projects. To get around this, I first trying using the query string to allow users to specify a distribution and project. While this worked, it resulted in long and ugly URLs. It took a while for me to be able to implement a cleaner solution. However, I eventually split each project into its own static HTML file. This meant that people could simply copy the URL from the address bar to link to a particular project. The main reason for doing this was that we felt the typical person would be interested in working on a specific project; most people won t be interested in navigating between the different projects. This change also allowed links that utilized the #graph anchor to function properly. Before, due to the way the page went about loading the project, trying to specify a specific project and #graph in the URL did not work properly. There is a plugin for jquery that allows tables to be sorted by particular columns. For tables that just contain text, this works fine without any issues. However, once I started using select boxes and text inputs, things got a bit messed up. After some research, I finally figured out how to use addParser to instruct the tablesorter plugin in how to sort each column in the table. In some of the earlier versions, I used some zebra stripes to make the table easy to read. Thanks to a suggestion from Paul Wise (pabs), I got rid of this striping and modified the code to color the rows based on the task s status. Complete tasks are green, in progress tasks are yellow, and incomplete tasks are red. This makes it very easy to find tasks that still need work as well as measure the overall status of a project. Sometimes, a large task list can feel very intimidating. That is why I added the ability to hide completed tasks with the check of a box. Matt wanted to take this one step farther; he wanted the ability to also hide tasks with a closed bug. This is why you will find 2 checkboxes at the top of the dashboard that allow you to custimize which tasks are visible. Eventually, I might add support for specifying this in the URL to allow groups to link to a particular view of the dashboard. In order to make it as easy as possible for new contributors to get involved with DEX projects, I wanted to have a way to document what a project is about and how to handle tasks. I decided to use the wiki for this. All of the per-project documentation lives at http://wiki.debian.org/DEX//
. You can even take advantage of wiki markup to format the documentation. The script will parse the HTML files generated by the wiki, do some minor cleanup, and then display the documentation at the top of the page. My original plan was to use the ?action=raw output, but the lack of formatting proved too restrictive. My second plan was to try and use something like BeautifulSoup or a regex to filter non-whitelisted tags out of the wiki-generated html. This failed and proved to be unnecessary. The wiki does a pretty decent job of preventing malicious markup from ending up on the dashboard. There is a second graph that is displayed on the dashboard. This graph shows the number of tasks each person has completed. The graph is sorted so that the tallest bars on the left, and the goal is to provide some immediate recognition of work done by contributors. Since we essentially allow anyone to go ahead and modify the dashboard, we knew it was important to have a method in place for dealing with abuse. Any malicious edits made on the wiki can easily be reverted. This idea of reverting to an earlier revision is what inspired me to use a second local git repository to store the projects/ directory. This directory stores all of the changes made via the web interface. Whenever the form is submitted or the script runs to update the list of tasks, any changes made to the projects/ directory are committed. This means that if a malicious user decides to delete everything on the dashboard, we can quickly and easily revert the changes. The revision history might also be interesting to analyze at a future date. When multiple people are collaborating on a project, an issue tracker can be quite useful. For some reason, we did not set one up until quite late into the project. Despite that, we are still using it to track known bugs and feature requests. The issue tracker will become even more useful once the dashboard starts to be utilized by more people. I spent a fair bit of time working on having the dashboard immediately respond to changes. For example, if you change the status of a task, the row color will instantly update. The form will also be submitted in the background, eliminating the need to hit submit to save the change. I also use ajax in some new dialogs that allow the user to create new projects and/or tasks via the web. While these forms are submitted in the background via ajax, I am unable to have the changes show up on the dashboard immediately. The generation of the task list is a bit slow, so having the script run more often is not really a good idea. The next step for the dashboard is to really open it up for testing. We hope to start up a new DEX project shortly. This will allow us to see which features work and which need fixing. It will also help us find some of the bugs that are probably hiding in the code. Finally, if you are interested in helping out with DEX or dextools, my code is available in a git repository (http://anonscm.debian.org/gitweb/?p=dex/gsoc2011.git) on alioth. There is also the issue tracker (https://alioth.debian.org/tracker/index.php?group_id=100600&atid=413120) where you can report bugs and request new features. Finally, you can join the debian-derivatives mailing list, join #debian-derivatives on OFTC, or contact me directly via email or on IRC (nhandler). I have really enjoyed working on dextools this summer. I would like to thank Matt Zimmerman, Stefano Zacchiroli, and everyone else who helped with the project. I look forward to working with all of you more in the future.

Compute clusters for Debian development and building final report Summary
-
The goal of this project was intended to have Eucalyptus cloud to
support ARM images so it allows Debian developers and users to be able
to use such facility for taks such package building, software
development (ie. Android) under a Debian pre-set image,
software testing many others. What was expected to have at the end is a modified version of Eucalyptus
Cloud that supports ARM images on the first place. To date this goal has
been reached but is not complete, read production-ready. Extensive test
needs to be done. Besides that we have another goal which is to get
Debian community to use this new extended tool. Project overview
-
Eucalyptus is a hybrid cloud computing platform which has a Open Source
(FLOSS) version. It s targetted to be used for PaaS (Platform as a
Service), IaaS (Infrastructure as a Service) and other distribution
models. It can be used also for cloud management. Given that it has
implemented the EC2, for computing, and the S3, for storage, API, it s
compatible with existing public clouds such Amazon EC2. Currently it
supports running i386 and amd64 images or NC (Node Controllers) in
Eucalyptus naming. Eucalyptus is a complex piece of software. It s architechture it s
modular composed by five components. Cloud Controller (CLC), Walrus (W),
Storage Controller (SC), Cluster Controller (CC) and Node Controller
(NC). The first three are written in Java and the remaining are written
in C. Our project modifications was targetted to the NC component,
altough there is a remaining task for hacking the UI to allow setting
the arch of the uploaded NC image instance. The Node Controller is in charge of setting the proper information for
Eucalyptus to be able to run virtualized images. Eucalyptus uses XEN and
KVM hyphervisor to handle internal virtualization subsystem, and
Libvirt, which is an abstraction of the existing virtualization
libraries, for program interfacing. Having that in mind we are back to our project. For our project to be
sucessful we had various tasks to do. Beginning with understanding such
complex piece of software, followed by hacking the requiered bits and
later integrate the work so it results in a useful tool. Our approach to
the project was then inline with such description. The project s history
I started my participation in GSoC approaching Steffen to discuss about
what was expected, or more accurately, what was in his mind. We
exchanged emails previous to my application and that resulted on my
application being submitted. From the beginning I should tell that I
wasn t much clear on the final product of the project, however we
refined ideas and goals during the weeks following to the official
begining of the project. What was clear for me, after all, is that for
this to see the light and gain adoption Eucalyptus code needed to be
dealt with. Our first task was review ARM image creation from scratch, using the
work done by Aurelien and Dominique in previous GSoC. I ve managed to
get an updated ARM image running under qemu-system-arm. The issues
presented in the past were almost unexistant now that the versatile
kernel is official. You can see this on my first report. After that being done and sometimes in parallel my main goal was then understand
the internals of the Eucalyptus software in order to figure out it s
feasibility, where do we need to extend and how big the task is, we
didn t knew upfront. From the beginning of the project Steffen was kind
to introduce me to the Eucalyptus developers and that have resulted in a
good outcome for Debian, IMHO, to date. Understanding Eucalyptus internals was quite a fun task to say the less. As you
can see on the first part of the report Eucalyptus is modularized and
the component I was expected to work with was the NC (Node
Controller). Given that I isolated my work focus, I started to focus on
learning the internals about that component. Node Controller as described is in charge of talking with
virtualization hyphervisors in order to arrange things to run guest
image instances. The module has basically one main component: handler.c,
in charge to talk to the appropiate hyphervisor and there are
extensions (think of OOP polymorphism but acknoledge it s plain C)
that interact with KVM or XEN. I figured that if qemu-kvm is ran in Hyphervisor mode we can manage to
run an ARM image with qemu-system-arm. Given that Eucalyptus has
interaction with KVM hyphervisor in place, this answered the question of
the project s feasibility. First green light on.
>From this point the scope reduced to interacting with the KVM handler
(node/handler_kvm.c) and extend it to support running an image that is
not amd64 or i386. NC makes use of libvirt to abstract interaction with Hyphervisors. So,
the next phase was learning about it s API and figure what s needed to
be modified next. Libvirt uses a XML file for setting Domain (in
libvirt s naming) definitions. So, Eucalyptus provides a Perl wrapper to
generate this file on runtime and allow the NC to invoke libvirt s API
to run the instance. Next task then, was adapt such script to support
ARM arch. The current script is taiolred for amd64 and i383. I worked on
that front and managed to get a script prototype, that can later be
improved and support more arch s. Generating an adequate Libvirt s XML Domain definition file for ARM can
be a heroic task. There are many things to have in mind given the
diversity of the ARM processor and vendors. I focused on the versatile
flavour given that I was going to test the image I built on the first
place and it ran fine under qemu-system-arm.
The Perl script wrapper then was adapted for such configuration and it
can be tested independently by issuing the following command: $ tools/gen_kvm_libvirt_xml arch arm The arch parameter is what I implemented and it s intended to be
called from the kvm handler on instance creation. With the extensibility
in mind I ve created a hash to associate the arch with their
corresponding emulator. our %arches = (
amd64 => /usr/bin/kvm ,
arm => /usr/bin/qemu-system-arm ,
); Added the arch parameter to the GetOptions() function and used
conditions to tell whether the user is looking for a particular arch,
arm in our case. The most important parts to be considered are the
, and entries. hvm $local_kvm There s also and that require to be tailored for arm. root=0800 As output the script generates an XML template that can be adapted to
your needs and it could be used and tested with tools like Libvirt s
virsh. So that, it can be useful independently of Eucalyptus. I managed
to get to this point before the midterm evaluation. Now that we had the XML wrapper almost done, the next task was to make
the handler call pass the arch as an argument to the script, so the
image is loaded with the proper settings and we are able to run it. Eucalyptus doesn t have a arch field for NC s instances. So, after approaching
Eucalyptus developers, with whom we had already being interacting, I
settled to my proposal of extending the ncInstance struct with an arch
field (util/data.h). The ncInstance_t struct stores the metadata for the
instance being created. It s used for storing runtime data as well as
network configuration and more. It was indeed the right place to add a
new field. I did so by creating the archId field.
Now I needed to make sure the arch information is stored and later used on the
libvirt s call. typedef struct ncInstance_t
char instanceId[CHAR_BUFFER_SIZE];
char imageId[CHAR_BUFFER_SIZE];
char imageURL[CHAR_BUFFER_SIZE];
char kernelId[CHAR_BUFFER_SIZE];
char kernelURL[CHAR_BUFFER_SIZE];
char ramdiskId[CHAR_BUFFER_SIZE];
char ramdiskURL[CHAR_BUFFER_SIZE];
char reservationId[CHAR_BUFFER_SIZE];
char userId[CHAR_BUFFER_SIZE];
char archId[CHAR_BUFFER_SIZE];
int retries; /* state as reported to CC & CLC */
char stateName[CHAR_BUFFER_SIZE]; /* as string */
int stateCode; /* as int */ /* state as NC thinks of it */
instance_states state; char keyName[CHAR_BUFFER_SIZE*4];
char privateDnsName[CHAR_BUFFER_SIZE];
char dnsName[CHAR_BUFFER_SIZE];
int launchTime; // timestamp of RunInstances request arrival
int bootTime; // timestamp of STAGING->BOOTING transition
int terminationTime; // timestamp of when resources are released (->TEARDOWN transition) virtualMachine params;
netConfig ncnet;
pthread_t tcb; /* passed into NC via runInstances for safekeeping */
char userData[CHAR_BUFFER_SIZE*10];
char launchIndex[CHAR_BUFFER_SIZE];
char groupNames[EUCA_MAX_GROUPS][CHAR_BUFFER_SIZE];
int groupNamesSize; /* updated by NC upon Attach/DetachVolume */
ncVolume volumes[EUCA_MAX_VOLUMES];
int volumesSize;
ncInstance; With that in place what was left was modifying the functions that
store/update the ncInstance data, and also the libvirt s function that
calls the gen_kvm_libvirt_xml script. I ve modified the following files:
- util/data.c
- node/handlers_kvm.c
- node/handlers. c,h
- node/test.c
- node/client-marshall-adb.c Most important the allocate_instance() function that is in charge of setting up
the instance metadata a prepare it to pass it to the handler, then
hyphervisor trough Libvirt s API. The function now has a new archId
parameter as well, to keep coherence with the field name. It also
handles whether the field is set or not. We (Eucalyptus developers and
I) haven t settled wether to initialize this field with a default value
or not. I d stepped up and initialized with a NULL value for this string
type var. if (archId != NULL)
strncpy(inst->archId, archId, CHAR_BUFFER_SIZE);
Stores the value only if it s passed to the function. This is essential to
don t break existing functionality and keep consistency for later releases.
With this we almost finished the part of extending Eucalyptus to support
arm images. It took quite long to get to that point. Next step: test. As I mentioned in my previous report the current Eucalyptus packaging
has issues. From the beginning I ve approached the pkg-eucalyptus team,
who were very hepful. So I myself set me up and joined the pkg team with
commit access to the repo. Even the GSoC is not intended for packaging
labour, I needed to clear things on that side because what we want is
adoption so anyone, say a DSA or a user, could setup a cloud that has
support for running arm instances under amd64 arch. Over the weeks between mid-term evaluation and past week I ve worked on
that front. Results were good, as you can see in the pkg-eucalyptus
mailing list and SVN repo.
Eucalyptus has a couple of issues that because of it s nature and complexity
triggered build errors. Those issues came from the Java side of the project and
few form the C-side. The C-part was a problem with AXIS2 Jar used to generate
stubs for later inclusion on build-time. There s no definitive solution to date
because one of the Makefile on gatherlog/Makefile issues a subshell call that
doesn t catches the AXIS_HOME environment variable. I ve worked around this
by defining it as a session env var from .zshrc. The other problem is related
to the Java libary versioning and most likely (we had to investigate further)
to groovy versioning. As I explained Eucalyptus has 3 components written in Java. The Java code uses
extensively the AXIS2 library for implementing webservices calls, the groovy
language for JVM, and many other Java libaries. Eucalyptus open source version
ships both online and offline versions. The difference is basically that
the offline version ships the Java libaries JAR files inside the source code,
so you can build with all required deps. Our former packaging used a file to list which Java libraries the package
depends on and it symlinked them using system wide installed packages. This
rather than helping out triggered a lot of problems I explaing with more detail
on the pkg-eucalyptus ml. I worked around this by telling the debian/rules
not to use such file to symlink and instead use the existing ones from
the source. The last weekend I managed to get to that point and built
sucessfully the software under Debian. I ve done that in order to have a
complete build-cycle for my changes, and then test. In fact today I ve
spotted and fixed a couple of bugs there. What s available now

To date we have a Eucalyptus branch where my patches are sent. The level of
extension is nearly complete, more testing needed. One missing bit is to
change the UI so that the user selects which arch her image is and that
value is passed to the corresponding functions on the Node Controller
component. We also have an ARM image that can be tested and later automated. I ve
recently learned about David Went s VMBuilder repo that extends Ubuntu s
vmbuilder to support image creationg. I might talk to him to adapt the tool
in order to support creation of arm images and use it to upload to an
Eucalyptus cloud. I ve also created a wiki page with different bits on which I was working on.
I ve yet need to craft it to be more educational. I guess I m going to use
this report as a source :) We also had more strong cooperation with the Eucalyptus project and
involved their developers on the packaging and this project, which is
something I consider a great outcome for this project and GSoC goals:
to attract more people to contribute to FLOSS. I ve also been contacted by
people from the Panda Project and we might cooperate also. Future work

I plan to keep working on the project regardless the GSoC ends. Our goal
as Debian could be integrating this into the Eucalyptus upstream
branch. We have good relations with them so expect news from that side.
I also plan to keep working with the Eucalyptus team and related
software in Debian, given that I m familiarized with the tools and
projects.
I m also planning to advocate SoC for Debian in my faculty. To date we
had already 4 students, IIRC, that have participated in the past. Project challenges and lessons
During the project I faced many challenges both in the personal side
and in the technical one. This part is a bit personal but I expect we
learn from this. First challenge was the where do I sit problem. My project was
particular, indeed quite different from the others on it s nature. I had
to work on a software that is not Debian s and then come and say Hey we
have this nice tool for you, come test it! . So, indeed, my focus was on
the understanding of such tool, Eucalyptus, and not much on looking back
at Debian because I didn t feel I had something to advertise yet and
indeed I got most valuable/useful feedback from Eucalyptus developers
rather than Debian s, which for the case is OK IMHO. I had great
mentoring. This situation probably looked a bit of isolation from my
side, from Debian s POV, but it was not intended it s just how it needed
to be IMHO. I felt that I wasn t contributing directly to the
project. I ve spoke about such thing with Steffen a couple of times. I d
like to say that it was also my concern but I probably failed on
communicating this, second challenge. Third challenge was more technical and related to the first one. Since I
was not writing any code for a Debian native package/program but instead for
other project I faced the situation of where to publish my
contributions. Eucalyptus had some issues on managing their FLOSS repo
and the current development one is outdated comparing to the
-src-offline 2.0.3 release. The project didn t fit pkg-eucalyptus repo
neither, even we thought to branch the existing trunk and ship my
contribs as quilt patches, but it involved a lot of more work and burn
on reworking something that has issues now. Later on time I branched the
bzr eucalyptus-devel Launchpad repo and synced there with the
src-offline code. I was slow to react on thing I can say. Fourth challenge was also technical and still dealing with. I was looking to
setup a machine to set a cloud and test my branch. The Dean of my faculty
kindly offered a machine but I ve never managed to get things arranged
with the technical team. Steffen and I discussed about this and evaluated
options, at the end we settled on pushing adoption rather than showcasing it.
Since for adoption we need a use case, I ve spend some SoC money on hardware
for doing this. I should have news this week on that side :) Finally, I d like to thank everyone on the Debian SoC team for this
opportunity to participate. I like to thank Steffen for his effort on
arranging things for me, Graziano from Eucalyptus for his advice on
working with the software code. The different people from Eucalyptus I
interacted with and showed interest on the project s sucess. My
classmates and teachers from the Computer Science School at UCSP in
Arequipa-Peru, friends from the computing community in Peru SPC and
finally my family. Thank you, I learned a lot, specially on the personal
side. As Randy Pausch put: The brick walls are there to give us a
chance to show how badly we want something. Resources
Please see the Wiki page[1] for any reference to the project s resources. 1- http://wiki.debian.org/SummerOfCode2011/BuildWithEucalyptus/ProjectLog Best regards,
Rudy

<meta content="text/html; charset=utf-8" equiv="content-type">

Hi everybody,

This is the 5th and the final report of my Google Summer of Code project for Debian,

Python Multi-Build for Python Extensions Packaging.

During the Google's Summer of Code 2011 period, I coded a tool to packaging Python extensions which can be built by distutils, autotools, cmake and scons. I finished tool for Python3.X (py3build), its CDBS files and working on integrating it with debhelper's sequencer and the tool for Python2.X (pybuild) and its BDS/DebHelper files. I will surely continue after GSoC finished and will continue improving the tool. The tool's git repository is here[1].

I'm a bit behind of my schedule. I finished all plugins for Python3.X except packaging module. Instead of that I worked on CDBS and DebHelper files. I finished CDBS files, also write a DebHelper but we decided to do DH file a different way. So I need to change it. I will port the tool to Python2.X.

In git repository there is contrib/ directory to contain CDBS and DebHelper files. CDBS files are in contrib/cdbs/ directory and debhelper files are in contrib/debhelper/ directory. I put original files if they exists (with .orig suffix) and modified files. I also created a new file for CDBS, called python-py3build.mk.in for handling all build systems. And modified python-distutils.mk.in and pyt<wbr>hon-autotools.mk.in files. All they are in git repository.

I'm still working on DebHelper file. After that I'll work on pybuild. And surely testing all of them and if any bug or problem occurs I will fix it.

Also, I need to improve my build system detection algorithm. At first, I thought that if there is multiple build system matches then show which are usable and then exit but I realized that in CDBS and DebHelper I need one build system. So even if there is multiple matches, it should return something. I'm also working on that.

For now that's all. Thanks everybody. It is a pleasure to contribute to Debian and participating from Google's Summer of Code. I will be in touch with Debian Project as a contributor.

[1] git://git.debian.org/~<wbr>mesutcan-guest/py3multibuild.<wbr>git

You might not know who Peter is because he s not very visible on Debian mailing lists. He s very active however and in particular on IRC. He was an admin of the OFTC IRC network at the time Debian switched from Freenode to OFTC. Nowadays he s a member of the Debian System Administration team who runs all the debian.org servers. If you went to a Debconf you probably met him since he s always looking for new signatures of his GPG key. He owns the best connected key in the PGP web of trust. He also wrote caff a popular GPG key signing tool. Raphael: Who are you? Peter: I m Peter Palfrader, also known as weasel. I m in my early 30s, born and raised in Innsbruck, Austria and am now living and working in Salzburg, Austria. In my copious free time, other than help running Debian s servers I also help maintaining the Tor project s infrastructure. Away from the computer I enjoy reading fiction (mostly English language Science Fiction and Fantasy), playing board games and going to the movies. Weather permitting, I also occasionally do some cycling. Raphael: How did you start contributing to Debian? Peter: I installed my first Debian the week slink came out. That was Debian 2.1 for the youngsters, in early 1999. The one thing I immediately liked about slink was that Debian s pppd supported RAS authentication which my university s dial-up system required. No way I d go back to SuSE 5.3 when I had working Internet with my Debian box. During that year I started getting involved in the German language Debian channel on IRCnet which got me in contact with some DDs. Christian Kurz (<shorty>) was working on Debian QA at the time and he asked my help in writing a couple of scripts. Some of that work, debcheck, still produces parts of the qa.d.o website, tho the relevance of that nowadays is probably negligible. While trying to learn more Perl earlier, I had written a program to produce syntax highlighted HTML for code snippets in various languages. I didn t really know what I was doing but it kinda worked, and probably still does since I still get mail from users every now and then. I figured that it would be really nice if people could just get my software together with Debian. According to code2html s Debian changelog the initial release of the package was done on a weekday at 2:30 in the morning early in 2000, and if my memory serves me correctly, shorty uploaded it shortly afterwards. I started packaging a couple of other piece of software and in the same year I sent my mail to the debian account managers to register my intent to become a DD. No new developers where being accepted at that time since the DAMs wanted to overhaul the entire process so I wasn t surprised to not get any immediate reply. Of course what the silence also meant was that the mail had been lost, but I only learned of that later when I took all my courage to ask DAM about the status of application a couple months later. Once that was sorted out I was assigned an AM, did the usual dance, and got my account late in November 2000. Raphael: Four years ago, the Debian System Administration team was a real bottleneck for the project and personal conflicts made it almost impossible to find solutions. You were eager to help and at some point you got dropped as a new member in that team. Can you share your story and how you managed the transition in the difficult climate at that time? Peter: Ah, that was quite the surprise for an awful lot of people, me included. Branden Robinson, who was our DPL for the 2005-2006 term, tried to get some new blood added to DSA who were at the time quite divided. He briefly talked to me on IRC some time in summer 2005, telling me I had come recommended for a role on the sysadmin team . In the course of these 15 minutes he outlined some of the issues he thought a new member of DSA would face and asked me if I thought I could help. My reply was cautiously positive, saying that I didn t want to step on anybody s toes but maybe I could be of some assistance. And that was the first and last of it, until some fine November day two years later I got an email from Phil Hands saying I ve just added you to the adm group, and added you to the debian-admin@d.o alias. and welcome on board . *blink* What!? My teammates at the time were James Troup (elmo), Phil Hands (fil), Martin Joey Schulze and Ryan Murray (neuro). The old team, while apparently not on good terms with one another, was however still around to do heavy lifting when required. I still remember when on my first or second day on the team two disks failed in the raid5 of ftp-master.debian.org aka ries. Neuro did the reinstall once new disks had arrived at Brown University. I m sure I d have been way out of my league had this job fallen to me. Fortunately my teammates were all willing and able to help me find whatever pieces of information existed that might help me learn how debian.org does its stuff. Unfortunately a lot of it only existed in various heads, or when lucky, in one of the huge mbox archives of the debian-admin alias or list. Anyway, soon I was able to get my hands dirty with upgrading from sarge to etch, which had been released about half a year earlier. Raphael: I know the DSA team has accomplished a lot over the last few years. Can you share some interesting figures? Peter: Indeed we have accomplished a lot. In my opinion the most important of these accomplishment is that we re actually once again a team nowadays. A team where people talk to one another and where nobody should be a SPoF. Since this year s debconf we are six people in the admin team: Tollef Fog Heen (Mithrandir) and Faidon Liambotis (paravoid) joined the existing members: Luca Filipozzi, Stephen Gran, Martin Zobel-Helas, and myself. Growing a core team, especially one where membership comes with uid0 on all machines, is not easy and that s why I m very glad we managed to actually do this step. I also think the infrastructure and our workflows have matured well over the last four years. We now have essential monitoring as a matter of course: Nagios not only checks whether all daemons that should be running are in fact running, but it also monitors hardware health of disks, fans, etc. where possible. We are alerted of outstanding security updates that need to be installed and of changes made to our systems that weren t then explicitly acked by one of us. We have set up a centralized configuration system, puppet, for some of our configuration that is the same, or at least similar, on all our machines. Most, if not all, pieces of software, scripts and helpers that we use on debian.org infrastructure is in publicly accessible git repositories. We have good communication with other teams in Debian that need our support, like the ftp folks or the buildd people. As for figures, I don t think there s anything spectacular. As of the time of our BoF at this year s DebConf, we take care of approximately 135 systems, about 100 of them being real iron, the other virtual machines (KVM). They are hosted at over 30 different locations, tho we are trying to cut down on that number, but that s a long and difficult process. We don t really collect a lot of other figures like web hits on www.debian.org or downloads from the ftp archive. The web team might do the former and the latter is pretty much impossible due to the distributed nature of our mirrors, as you well know. Raphael: The DSA team has a policy of eating its own dog food, i.e. you re trying to rely only on what s available in Debian. How does that work out and what are the remaining gaps? Peter: Mostly Debian, the OS, just meets our needs. Sure, the update frequency is a bit high, we probably wouldn t mind a longer release cycle. But on the other hand most software is recent enough. And when it s not, that s easy to fix with backports. If they aren t on backports.debian.org already, we ll just put them there (or ask somebody else to prepare a backport for us) and so everybody else benefits from that work too. Some things we need just don t, and probably won t, exist in Debian. These are mainly proprietary hardware health checks like HP s tools for their servers, or various vendors programs to query their raid controller. HP actually makes packages for their stuff which is very nice, but other things we just put into /usr/local, or if we really need it on a number of machines, package ourselves. The push to cripple our installers and kernels by removing firmware was quite annoying, since it made installing from the official media next to impossible in some cases. Support for working around these limitations has improved with squeeze so that s probably ok now. One of the other problems is that especially on embedded platforms most of the buildd work happens on some variation of development boards, usually due to increased memory and hard disk requirements than the intended market audience. This often implies that the kernel shipped with Debian won t be usable on our own debian.org machines. This makes keeping up with security and other kernel fixes way more error prone and time intensive. We keep annoying the right people in Debian to add kernel flavors that actually boot on our machines, and things are getting better, so maybe in the future this will no longer be a problem. Raphael: If you could spend all your time on Debian, what would you work on? Peter: One of the things that I think is a bit annoying for admins that maintain machines all over the globe is mirror selection. I shouldn t have to care where my packages come from, apt-get should just fetch them from a mirror, any mirror, that is close by, fast and recent. I don t need to know which one it was. We have deployed geodns for security.debian.org a while ago, and it seems to work quite well for the coarse granularity we desired for that setup, but geodns is an ugly hack (I think it is a layer violation), it might not scale to hundreds or thousands of mirrors, and it doesn t play well with DNSSEC. What I d really like to see is Debian support apt s mirror method that I think (and I apologize if I m wronging somebody) Michael Vogt implemented recently. The basic idea is that you simply add deb mirror://mirror.debian.org/ or something like that to your sources.list, and apt goes and asks that server for a list of mirrors it should use right now. The client code exists, but I don t know how well tested it is. What is missing is the server part. One that gives clients a mirror, or list of mirrors, that are close to them, current, and carry their architecture. It s probably not a huge amount of work, but at the same time it s also not entirely trivial. If I had more time on my hands this is something that I d try to do. Hopefully somebody will pick it up. Raphael: What motivates you to continue to contribute year after year? Peter: It s fun, mostly. Sure, there are things that need to be done regularly that are boring or become so after a while, but as a sysadmin you tend to do things once or twice and then seek to automate it. DSA s users, i.e. DDs, constantly want to play with new services or approaches to make Debian better and often they need our support or help in their endeavors. So that s a constant flow of interesting challenges. Another reason is that Debian is simply where some of my friends are. Working on Debian with them is interacting with friends. I not only use Debian at debian.org. I use it at work, I use it on my own machines, on the servers of the Tor project. When I was with OFTC Debian is what we put on our machines. Being a part of Debian is one way to ensure what Debian releases is actually usable to me, professionally and with other projects. Raphael: Is there someone in Debian that you admire for their contributions? Peter: That s a hard one. There are certainly people who I respect greatly for their technical or other contributions to Debian, but I don t want to single anybody out in particular. I think we all, everyone who ever contributed to Debian with code, support or a bug report, can be very proud of what we are producing one of the best operating systems out there.

---

Thank you to Peter for the time spent answering my questions. I hope you enjoyed reading his answers as I did. Subscribe to my newsletter to get my monthly summary of the Debian/Ubuntu news and to not miss further interviews. You can also follow along on Identi.ca, Twitter and Facebook.

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