I had a nice conversation with the people at Tap N Tap (who produce the firmware image used on the Viewsonic gtab tablets) today, so with luck we'll see some progress on that front in the near future.
overlay /var/lib/schroot/union/overlay tmpfs defaults 0 0Build times are much faster this way because all write I/O is directed to the RAM
The two first interviews were dedicated to long-time Debian developers. This time I took the opposite approach, I interviewed David Kalnischkies who is not (yet) a Debian developer. But he s contributing to one of the most important software within Debian the APT package manager since 2009. You can already see him in many places in Debian sharing his APT knowledge when needed.
English is not his native language and he s a bit shy, but he accepted the interview nevertheless. I would like to thank him for the efforts involved and I hope his story can inspire some people to take the leap and just start helping My questions are in bold, the rest is by David.
Who are you?
I am David Kalnischkies, 22 years old, living in the small town Erbach near Wiesbaden in Germany and I m studying computer science at the TU Darmstadt. Furthermore I am for more than half a decade now young group leader of my hometown.
I never intended to get into this position, but it has similarities with my career in this internet-thingy here. I don t remember why, but in April 2009 I was at a stage that some simple bugs in APT annoyed me so much that I grabbed the source, and most importantly I don t know why I did it but I published my changes in Mai with #433007, a few more bugs and even a branch on launchpad. And this public branch got me into all this trouble in June: I got a mail from Mr. package managment Michael Vogt regarding this branch
A few days later I joined an IRC session with him and closely after that my name appeared for the first time in a changelog entry. It s a strange but also addicting feeling to read your own name in an unfamiliar place. And even now after many IRC discussions, bugfixes and features, three Ubuntu Developer Summits and a Google Summer of Code in Debian, my name still appear in places I have never even thought about e.g. in an interview.
What s your biggest achievement within Debian?
I would like to answer MultiArch in APT as it was my Google Summer of Code project, but as it has (not much) use for the normal user at this point will hopefully change for wheezy I chose three smaller things in squeeze s APT that many people don t even know yet:
APT didn t accept release codenames as target release was one of the first things I fixed. If I had asked someone if that would be a good starting point the answer would have been a clear no , but I didn t search for a good starting point
As a kid I can start playing football by just walking on the field and play or I can sit near the field, watching the others play, while analyzing which position would be the best for me to start ruling out one by one as the technical requirements seem too high Oh bicycle kick that sounds complicated I can t do that
Julian Andreas Klode is working on a APT replacement, there s also Cupt by Eugene V. Lyubimkin. Both projects started because their authors are not satisfied with APT, they find APT s code difficult to hack partly due to the usage of C++. Do you share their concerns and what s your opinion on those projects?
I don t think C++ is a concern in this regard, after all cupt is currently rewritten to C++0x and APT2 started in vala and is now C + glib last time I checked at least. I personally think that something is wrong if we need to advertise an application by saying in which language it is written
The major problem for APT is probably that the code is old : APT does its job for more than 12 years now, under different maintainers with an always changing environment around it: so there are lines in APT which date from a time when nobody knew what a Breaks dependency is, that packages can have long descriptions which can be translated or even that package archives can be signed with a gpg key! And yet we take all those for granted today. APT has proven to adapt to these changes in the environment and became in this process very popular. So I don t think the point is near (if it will come at all) that APT can go into retirement as it is completely replaced by something else.
The competitors one the other hand have their first 12 years still to go. And it will be interesting to see how they will evolve and what will be the state of the art in 2022
But you asked what I think about the competitors: I prefer the revolution from inside simply because I can see effects faster as more users will profit from it now. Cupt and co. obviously prefer the normal revolution. The goal is the same, creating the best package manager tool, but the chosen way to the goal is different. aptitude and cupt have an interactive resolver for example: that s something I dislike personally, for others that is the ultimate killer feature. cupt reading the same preference file as APT will have a different pinning result, which we should consider each time someone mentions the word drop-in replacement .
APT2 isn t much more than the name which I completely dislike currently from a user point of view, so I can t really comment on that. All of them make me sad as each line invested in boilerplate code like configuration file parsing would be in my eyes better be spent in a bugfix or new feature instead, but I am not here to tell anyone what they should do in their free time
But frankly, I don t see them really as competitors: I use the tools I use, if other do that too that s good, if not that s their problem. The thing that annoys me really are claims like plan is to remove APT by 2014 as this generates a vi vs. emacs like atmosphere we don t need. If some people really think emacs is a good editor who cares?
I really hope we all can drink a beer in 2022 in Milliways, the restaurant at the end of the package universe, remembering the good old 2010 
Is there someone in Debian that you admire for his contributions?
No, not one, many!
Michael Vogt who has nearly the monopole of package manager maintainer by being upstream of APT, synaptics and software center to name only the biggest and still has the time to answer even the dumbest of my questions. Jason Gunthorpe for being one of the initial developers behind deity who I will probably never meet in person beside in old comments and commit logs. Christian Perrier for caring so much about translations. Obey Arthur Liu as a great admin for Debian s participation in Google s Summer of Code. Paul Wise for doing countless reviews on debian-mentors which are a good source of information not only for the maintainer of the package under review.
I guess I need to stop here because you asked for just one. So let s end with some big words instead: I am just a little cog in the big debian wheel
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As I mentioned recently, the Ubuntu Technical Board is reviewing the most popular topics in Ubuntu Brainstorm and coordinating official responses on behalf of the project. This means that the most popular topics on Ubuntu Brainstorm receive expert answers from the people working in these areas.
This is the first batch, and we plan to repeat this process each quarter. We ll use feedback and experiences from this run to improve it for next time, so let us know what you think.
Power management (idea #24782)
Laptops are now outselling desktops globally, and laptop owners want to get the most out of their expensive and heavy batteries. So it s no surprise that people are wondering about improved power management in Ubuntu. This is a complex topic which spans the Linux software stack, and certainly isn t an issue which will be solved in the foreseeable future, but we see a lot of good work being done in this area.
To tell us about it, Amit Kucheria, Ubuntu kernel developer and leader of the Linaro working group on Power Management, contributed a great writeup on this topic, with technical analysis, tips and recommendations, and a look at what s coming next.
I am going to attempt to summarize the various use profiles and what Ubuntu does (or can do) to prolong battery life in those profiles. Power management, when done right, should not require the user to make several (difficult) choices. It should just work providing a good balance of performance and battery life.IP address conflicts (idea #25648) IP addressing is a subject that most people should never have to think about. When something isn t working, and two computers end up with the same IP address, it can be hard to tell what s wrong. I was personally surprised to find this one near the top of the list on Ubuntu Brainstorm, since it seems unlikely to be a very common problem. Nonetheless, it was voted up, and we re listening. There is a tool called ipwatchd which is already available in the package repository, and was created specifically to address this problem. This seems like a further indication that this problem may be more widespread than I might assume. The idea has already been marked as implemented in Brainstorm based on the existence of this package, but that doesn t help people who have never heard of ipwatchd, much less found and installed it. What do you think? Have you ever run into this problem? Would it have helped you if your computer had told you what was wrong, or would it have only confused you further? Is it worth considering this for inclusion in the default install? Post your comments in Brainstorm. Selecting the only available username to login (idea #6974) Although Linux is designed as a multi-user operating system, most Ubuntu systems are only used by one person. In that light, it seems a bit redundant to ask the user to identify themselves every time they login, by clicking on their username. Why not just preselect it? Indeed, this would be relatively simple to implement, but the real question is whether it is the right choice for users. Martin Pitt of the Ubuntu Desktop Team notes that consistency is an important factor in ease of use, and asks for further feedback.
So in summary, we favored consistency and predictablility over the extra effort to press Enter once. This hasn t been a very strong opinion or decision, though, and the desktop team would be happy to revise it.Icon for .deb packages (idea #25197) Building on the invaluable efforts of Debian developers, we work hard to make sure that people can get all of the software they need from Ubuntu repositories through Software Center and APT, where they are authenticated and secure. However, in practice, it is occasionally necessary for users to work with .deb files directly. Brainstorm idea 25197 suggests that the icon used to represent .deb packages in the file manager is not ideal, and can be confusing. Matthew Paul Thomas of the Canonical Design Team responds with encouragement for deb-thumbnailer, which makes the icon both more distinctive and more informative. He has opened bug 685851 to track progress on getting it packaged and into the main repository.
I have reviewed the proposed solutions with Michael Vogt, our packaging expert. Solution #1 is straightforward, but we particularly like solutions #5 and #10, using a thumbnailer to show the application icon from inside each package.Keeping the time accurate over the Internet by default (idea #25301) It s important for an Internet connected computer to know the correct time of day, which is why Ubuntu has included automatic Internet time synchronization with NTP since the very first release (4.10 warty ). So some of us were a little surprised to see this as one of the most popular ideas on Ubuntu Brainstorm. Colin Watson of the Ubuntu Technical Board investigated and discovered a case where this wasn t working correctly. It s now fixed for Ubuntu 11.04, and Colin has sent the patches upstream to Debian and GNOME.
My first reaction was hey, that s odd I thought we already did that? . We install the ntpdate package by default (although it s deprecated upstream in favour of other tools, but that shouldn t be important here). ntpdate is run from /etc/network/if-up.d/ntpdate, in other words every time you connect to a network, which should be acceptably frequent for most people, so it really ought to Just Work by default. But this is one of the top ten problems where users have gone to the trouble of proposing solutions on Brainstorm, so it couldn t be that simple. What was going on?More detail in GNOME system monitor (idea #25887) Under System, Preferences, System Monitor, you can find a tool to peek under the hood at the Linux processes which power every Ubuntu system. Power users, hungry for more detail on their systems inner workings, voted to suggest that more detail be made available through this interface. Robert Ancell of the Ubuntu Desktop Team answered their call by offering to mentor a volunteer to develop a patch, and someone has already stepped up with a first draft. Help the user understand when closing a window does not close the app (idea #25801) When the user clicks the close button, most applications obediently exit. A few, though, will just hide, and continue running, because they assume that s what the user actually wants, and it can be hard to tell which has happened. Ivanka Majic, Creative Strategy Lead at Canonical, shares her perspective on this issue, with a pointer to work in progress to resolve it.
This is more than a good idea, it s an important gap in the usability of most of the desktop operating systems in widespread use today.Ubuntu Software Centre Removal of Configuration Files (idea #24963) One feature of the Debian packaging system used in Ubuntu is that it draws a distinction between removing a package and purging it. Purging should remove all traces of the package, such that installing and then immediately purging a package should return the system to the same state. Removing will leave certain files behind, including system configuration files and sometimes runtime data. This subtle distinction is useful to system administrators, but only serves to confuse most end users, so it s not exposed by Software Center: it just defaults to removing packages. This proposal in Ubuntu Brainstorm suggests that Software Center should purge packages by default instead. Michael Vogt of the Ubuntu Foundations Team explains the reasoning behind this default, and offers an alternative suggestion based on his experience with the package management system.
This is not a easy problem and we need to carefully balance the needs to keep the UI simple with the needs to keep the system from accumulating cruft.Ubuntu One file sync progress (idea #25417) Ubuntu One file synchronization works behind the scenes, uploading and downloading as needed to replicate your data to multiple computers. It does most of its work silently, and it can be hard to tell what it is doing or when it will be finished. John Lenton, engineering manager for the Ubuntu One Desktop+ team, posts on the AskUbuntu Q&A site with tools and tips which work today, and their plans to address this issue comprehensively in the future. Multimedia performance (idea #24878) With a cornucopia of multimedia content available online today, it s important that users be able to access it quickly and easily. Poor performance in the audio, video and graphics subsystems can spoil the experience, if resource-hungry multimedia applications can t keep up with the flow of data. Allison Randal, Ubuntu Technical Architect, answers with an analysis of the problem and the proposed solutions, an overview of current activity in this area, and pointers for getting involved.
The fundamental concern is a classic one for large systems: changes in one part of the system affect the performance of another part of the system. It s modestly difficult to measure the performance effects of local changes, but exponentially more difficult to measure the network effects of changes across the system.
The buglist now:
As part of my work for EDF, I ve had to package and integrate a set of tools for performance measurement and profiling of HPC code. This toolbox comprises tools for analysis of both sequential and parallel codes, MPI communications profiling and, of course, visualization frontends.
Without going into too much details, here s the list:
Mockup of mobile UI
I know ecologists often come with great ideas how to save some random resource. There was a "green" font, which contained holes and was supposed to save ink/toner from printers. It turned out not to be that big saver as the font itself was actually a bit wider than usual...
Today I got to know about "new" file format called WWF. Technically it is just a PDF with disabled printing. Well at least it is not a new format, so users of other operating systems (WWF software is available for Mac OS X only right now) are not lost and can use existing tools to view the files (on Linux you can for example use Evince).
And if Evince rejects to print this document, just disable these restrictions:
gconftool-2 -s /apps/evince/override_restrictions -t bool 1
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So I had an idea: why not build him a box that has some switches that he can play with? And why not make it a project we can do together?
So back in, I think, July, we went to the hardware store. We bought some AC power cord, some electrical boxes, and assorted supplies. I had some other supplies on hand already, so we didn t need to spend much. I asked Jacob today if he remembered that day, and he said, Oh yes! And I got popcorn to eat there! Which was, indeed, quite true.
I had some surplus plywood, so I cut out two squares, one for a front and one for a back. Then, in 10-minute increments every so often over the last few months, Jacob would say, Dad, shall we go work on my switchbox? And by that, he meant that I should work on the switchbox while he pretends that my tape measures are train engines or raids the corner where disused toys are stored. After 10 minutes, he d be done. Which meant that after I gathered up my tools, remembered where I was, and got to work, I made only a few minutes progress each week. But that was fine.
This week, I got it all wired up. It doesn t have its sides and back yet, but it was enough for Jacob to try it out.
To add to the excitement just that much more, I spent a few dollars at the hardware store today and bought him four light bulbs: 25W red, green, and blue bulbs, and a 7.5W miniature white one. I let him choose two of them to use in the switchbox.
So he started playing with it, and after just a few seconds, said, Dad, I am very very very very excited about my switchbox! And a little while later, he burst into applause, and announced, Dad, my switchbox is so so so so so fun! It is also so so so so so silly the lightbulb is green!
I wired up a regular light switch that is a master on/off switch. Then the dimmer switch controls the light bulb socket but not the outlet. The dimmer switch also has a pushbutton on/off circuit, so there are plenty of opportunities for discovery.
This is a play with it only with dad s supervision item for now, but after supper, he insisted in bringing Terah downstairs to show her how to use it too. He happily showed off the red and green lights, how to turn them on, and how to make the red light dimmer. I suggested he also show her what happens when he pushes on the dimmer switch, which he happily did, and also explained to her what it does.
He was just amazingly excited. Every so often he d tell me how excited or happy he was, and some fun fact about it all.
And, really, that s what I hoped would happen. I didn t accompany it with these words, but I hope that projects like this can serve to remind everyone that toys and gifts don t have to cost hundreds of dollars; they can be made with a few dollars supplies and some surplus materials laying around the house.
But not only that, but the best parts of this project were the ones Jacob and I spent together from the time when just the two of us went shopping at the hardware store, through all those 10-minute times where he pretended my tape measures were locomotives and the tape was their track, right to today when he got to try it out. It took a long time, but when I asked him if it was worth the wait, he said Yes! and clapped while jumping up and down.
And, I have to admit, as I got into the car with my $4 worth of light bulbs today, I was almost as excited as him, just to see what he would do.
That s the best part: I got to experience Jacob s joy right along with him. It s a time when I really enjoy being a dad.
For my birthday back in October, my wonderful wife gave me a Kindle 3 from Amazon. I d been considering other e-book readers for quite some time, but I had mostly ignored the Kindle due to the lack of EPUB support and a general dislike of Amazon s DRM enforcement. In the end, the superior hardware and ecosystem of the Kindle overpowered those concerns and overall I m very pleased with the purchase. The screen is amazing, literally just like reading off a piece of paper and the selection of books is OK. I ve been buying almost all my books from Amazon to date since it s so easy (the Whispernet is amazingly quick!) but it s not terribly difficult to get EPUBs from elsewhere onto the device after a quick run through Calibre to turn them into a MOBI file, so I keep telling myself I ve still got some flexibility.
Almost as much fun as reading on the device has been learning about how it works. The Mobile Read forums have lots of step by step posts on how to do specific tasks like replacing the screensaver image, but they don t give much background detail on how the Kindle is actually operating which is what really interests me. Luckily among all the step by step posts I also found a usbnetwork package which also adds an SSH server to the Kindle, so after installing that and then SSHing in to my Kindle I ve been poking around.
Under the cover the Kindle reveals a fairly standard Linux installation. While the hardware and IO devices are obviously unique, compared to something like an Android phone, the Kindle is refreshingly normal .
Hardware
/proc rather than as a device. With a bit of digging I found some simple constants that when written to the proc files cause the screen to display the standard boot/progress/upgrading images. I haven t deciphered how to make more complex updates to the display yet./opt/amazon/ebook and consists of lots of Java classes. The system uses the cvm Java environment from Sun/Oracle which is specialised for embedded low-memory devices like this. The framework appears to take over most of the co-ordination, management and interaction tasks once it has started up.sendlogs scripts I d noticed and a few syslog lines containing GPS co-ordinates that had been pasted on the Mobile Read forums. I can t find any trace of GPS co-ordinates in any syslog messages I ve seen on my device, but there is definitely information about the cell sites that my Kindle can see, the books that I m opening and where I m up to in them:
101206:235431 wand[2515]: I dtp:diag: t=4cfd77b7,MCC MNC=272 01,Channel=10762,Band=WCDMA I IMT 2000,Cell ID=1362209,LAC=3021,RAC=1
,Network Time=0000/00/00 00.00.00,Local Time Offset=Not provided,Selection Mode=Automatic,Test Mode=0,Bars=4,Roaming=1,RSSI=-88,Tx
Power=6,System Mode=WCDMA,Data Service Mode=HSDPA,Service Status=Service,Reg Status=Success,Call Status=Conversation,MM Attach St
ate=Attach accept,MM LU State=LU update,GMM Attach State=Attach accept,GMM State=Registered,GMM RAU State=Not available,PDP State=
Active,Network Mode=CS PS separate attach mode,PMM Mode=Connected,SIM Status=Valid; PIN okay; R3,MM Attach Error=No error,MM LU Er
ror=No error,GMM Attach Error=No error,GMM RAU Error=Not available,PDP Rej Reason=No error,Active/Monitored Sets=0;39;-11 1;180;-1
5,RSCP=-111,DRX=64,HSDPA Status=Active,HSDPA Indication=HSDPA HSUPA unsupp,Neighbor Cells=,Best 6 Cells=,Pathloss=,MFRM=,EGPRS Ind
ication=,HPLMN=,RPLMN=272;01 ,FPLMN=234;33 234;30 234;20 272;05 ,n=1:
101206:235758 cvm[3426]: I Reader:BOOK INFO:book asin=B003IWZZ3Y,file size=233168,file last mod date=2010-11-27 19.18.22 +0000,con
tent type=ebook,length=MobiPosition_ 465747,access=2010-12-06 09.44.32 +0000,last read position=MobiPosition_ 464387,isEncrypted=f
alse,isSample=false,isNew=false,isTTSMetdataPresent=false,isTTSMetadataAllowed=true,fileExtn=azw:
101206:233416 udhcpc[5639]: Offer from server xxx.xxx.2.254 received
101206:233416 udhcpc[5639]: Sending select for xxx.xxx.2.10...
Interestingly you can see from the last two lines, that Amazon has taken some care to preserve privacy by not including the full IP address given to the device by my local Wifi network, so in light of that I find it interesting that they decided not to obfuscate the Cell and Book IDs in those respective log messages too. Seems rather inconsistent.
As to how and when these logs are sent to Amazon, the picture is a little bit murky. Every 15 minutes tinyrot runs out of cron and rotates /var/log/messages if it is greater than 256k in size. Rotated logs are stored into /var/local/log under filenames like messages_00000044_20101207000006.gz and alongside the log files are a set of state files named nexttosendfile, messages_oldest, messages_youngest. Something regularly sweeps through this directory to update the state and remove the old logs (after sending them up to Amazon I assume). I suspect that something is buried in the Java application code mentioned above.
On the whole the Kindle is a fascinating piece of technology. It delivers a wonderful reading experience on top of a familiar Linux system and is going to provide me with many more hours of entertainment as I unpack all the tricks and techniques that have gone into this device. I would recommended it as a present for geeks everywhere.
On a private mailing list there was some discussion, and I had an
outburst. Summarising very roughly, someone said bad things about
their competitor, without (at first) offering any justification.
Here's a version of my outburst, edited to remove references to
the actual topic and identifyable people. I thought it might amuse
me in fifty years or so to see how full of myself I was.
The relationship between Debian and Ubuntu has been the subject of many
vigorous debates over the years, ever since Ubuntu s launch in 2004.
Six years later, the situation has improved and both projects
are communicating better. The Natty Narwhal Ubuntu Developer
Summit (UDS) featured like all UDS for more than 2 years a Debian
Health Check session where current cooperation issues and projects are
discussed. A few days after that session, Lucas Nussbaum gave a talk
during the mini-Debconf
Paris detailing the relationship between both projects, both at the
technical and social level. He also shared some concerns for Debian s
future and gave his point of view on how Debian should address them.
Both events give valuable insights on the current state of
the relationship.
Lucas Nussbaum s Debian-Ubuntu talk
Lucas started by introducing himself. He s an Ubuntu developer since 2006
and a Debian developer since 2007. He has worked to improve the collaboration
between both projects, notably by extending the Debian infrastructure to show
Ubuntu-related information. He attended conferences for both projects
(Debconf, UDS) and has friends in both communities. For all of these reasons,
he believes himself to be qualified to speak on this topic.
Collaboration at the technical level
He then quickly explained the task of a distribution: taking upstream
software, integrating it in standardized ways, doing quality assurance on
the whole, delivering the result to users, and assuring some support
afterward. He pointed out that in the case of Ubuntu, the distribution
has one special upstream: Debian.
Indeed Ubuntu gets most of its software from Debian (89%), and
only 7% are new packages coming from other upstream projects (the
remaining 4% are unknown, they are newer upstream releases of software
available in Debian but he was not able to find out whether the Debian
packaging had been reused or not). From all the packages imported from
Debian, 17% have Ubuntu-specific changes. The reasons for those changes
are varied: bugfixes, integration with Launchpad/Ubuntu One/etc., or
toolchain changes. The above figures are based on Ubuntu Lucid (10.04) while
excluding many Ubuntu-specific packages (language-pack-*, language-support-*,
kde-l10n-*, *ubuntu*, *launchpad*).
The different agendas and the differences in philosophy (Debian
often seeking perfect solutions to problems; Ubuntu accepting
temporary suboptimal workarounds) also explain why so many packages are
modified on the Ubuntu side. It s simply not possible to always do the
work in Debian first. But keeping changes in Ubuntu requires a lot of work
since they merge with Debian unstable every 6 months. That s why they have
a strong incentive to push changes to upstream and/or to Debian.
There are 3 channels that Ubuntu uses to push changes to Debian: they
file bug reports (between 250 to 400 during each Ubuntu release cycle),
they interact directly with Debian maintainers (often the case when
there s a maintenance team), or they do nothing and hope that the Debian
maintainer will pick up the patch directly from the Debian
Package Tracking System (it relays information provided by patches.ubuntu.com).
Lucas pointed out that those changes are not the only thing that
Debian should take back. Ubuntu has a huge user base resulting in lots of
bug reports sitting in Launchpad, often without anyone taking care of
them. Debian maintainers who already have enough bugs on their
packages are obviously not interested in even more bugs, but those who are
maintaining niche packages, with few reports, might be interested by the
user feedback available in Launchpad. Even if some of the reports are
Ubuntu-specific, many of them are advance warnings of problems
that will affect Debian later on, when the toolchain catches up with
Ubuntu s aggressive updates. To make this easier for Debian maintainers,
Lucas improved the Debian Package Tracking System so that they can easily
get Ubuntu bug reports for their packages even without interacting with
Launchpad.
Human feelings on both sides
Lucas witnessed a big evolution in the perception of Ubuntu on the Debian
side. The initial climate was rather negative: there were feelings of its work
being stolen, claims of giving back that did not match the observations of
the Debian maintainers, and problems with specific Canonical employees
that reflected badly on Ubuntu as a whole. These days most Debian developers find
something positive in Ubuntu: it brings a lot of new users to Linux, it
provides something that works for their friends and family, it brings new
developers to Debian, and it serves as a technological playground for
Debian.
On the Ubuntu side, the culture has changed as well. Debian is no
longer so scary for Ubuntu contributors and contributing to Debian is The
Right Thing to do. More and more Ubuntu developers are getting involved in Debian
as well. But at the package level there s not always much to contribute, as
many bugfixes are only temporary workarounds. And while Ubuntu s
community follows this philosophy, Canonical is a for-profit company that
contributes back mainly when it has compelling reasons to do so.
Consequences for Debian
In Lucas s eyes, the success of Ubuntu creates new problems. For many
new users Linux is a synonym for Ubuntu, and since much innovation happens
in Ubuntu first, Debian is overshadowed by its most popular derivative.
He goes as far as saying that because of that Debian becomes less
relevant .
He went on to say that Debian needs to be relevant because the
project defends important values that Ubuntu does not. And it needs to
stay as an independent partner that filters what comes out of Ubuntu,
ensuring that quality prevails in the long term.
Fixing this problem is difficult, and the answer should not be
to undermine Ubuntu. On the contrary, more cooperation is needed. If
Debian developers are involved sooner in Ubuntu s projects, Debian will
automatically get more credit. And if Ubuntu does more work in
Debian, their work can be showcased sooner in the Debian context as
well.
The other solution that Lucas proposed is that Debian needs to
communicate on why it s better than Ubuntu. Debian might not be better for
everybody but there are many reasons why one could prefer Debian over
Ubuntu. He listed some of them: Debian has better values
since it s a volunteer-based project where decisions are made publicly
and it has advocated the free software philosophy since 1993. On the other hand,
Ubuntu is under control of Canonical where some decisions are imposed, it
advocates some proprietary web services (Ubuntu One), the installer
recommends adding proprietary software, and copyright assignments are
required to contribute to Canonical projects.
Debian is also better in terms of quality because every package has a
maintainer who is often an expert in the field of the package. As a
derivative, Ubuntu does not have the resources to do the same and instead
most packages are maintained on a best effort basis by a limited set of
developers who can t know everything about all packages.
In conclusion, Lucas explained that Debian can neither ignore Ubuntu
nor fight it. Instead it should consider Ubuntu as a
chance and should leverage it to get back in the center
of the FLOSS ecosystem .
The Debian health check UDS session
While this session has existed for some time, it s only the second
time that a Debian Project Leader was present at UDS to discuss collaboration
issues. During UDS-M (the previous summit), this increased involvement
from Debian was a nice surprise to many. Stefano
Zacchiroli the Debian leader collected and shared the
feedback of Debian developers and the session ended up being very
productive. Six months later is a good time to look back and verify
if decisions made during UDS-M (see blueprint)
have been followed through.
Progress has been made
On the Debian side, Stefano set up a Derivatives
Front Desk so that derivative distributions (not just Ubuntu)
have a clear point of
contact when they are trying to cooperate but don t know where to start.
It s also a good place to share experiences among the various
derivatives. In parallel, a #debian-ubuntu channel has been started on OFTC (the
IRC network used by Debian). With more than 50 regulars coming from both
distributions, it s a good place for quick queries when you need advice
on how to interact with the distribution that you re not familiar
with.
Ubuntu has updated its documentation to prominently feature how to
cooperate with Debian. For example, the sponsorship process
documentation explains how to forward patches both to the upstream
developers and to Debian. It also recommends ensuring that the patch
is not Ubuntu-specific and gives some explanation on how to do it (which
includes checking against a list of common packaging
changes made by Ubuntu). The Debian Derivative Front Desk is
mentioned as a fallback when the Debian maintainer is unresponsive.
While organizing Ubuntu Developer
Week, Ubuntu now reaches out to Debian developers and tries to have
sessions on working with Debian . Launchpad has also been extended to provide a list of bugs with
attached patches and that information has been integrated in the Debian
Package Tracking system by Lucas Nussbaum.
Still some work to do
Some of the work items have not been completed yet: many
Debian maintainers would like a simpler way to issue a sync request (a
process used to inject a package from Debian into Ubuntu).
There s a requestsync command line tool provided by the ubuntu-dev-tools package (which is available in Debian) but it s not yet usable because
Launchpad doesn t know the GPG keys of Debian maintainers.
Another issue concerns packages which are first introduced in Ubuntu.
Most of them have no reason to be Ubuntu-specific and should also end up
in Debian. It has thus been suggested that people packaging new software
for Ubuntu also upload them to Debian. They could however
immediately file a request
for adoption (RFA) to find another Debian maintainer if they
don t plan to maintain it in the long term. If Ubuntu doesn t make
this effort, it can take a long time until someone decides to reintegrate
the Ubuntu package into Debian just because nobody knows about it.
This represents an important shift in the Ubuntu process and it s not
certain that it s going to work out. As with any important policy change,
it can take several years until people are used to it.
Both issues have been rescheduled for this release cycle, so they re still on the agenda.
This time the UDS session was probably less interesting than the
previous one. Stefano explained
once more what Debian considers good collaboration practices: teams
with members from both distributions, and forwarding of bugs
if they have been well triaged and are known to apply to Debian. He also
invited Ubuntu to discuss big changes with Debian before implementing
them.
An interesting suggestion that came up was that some Ubuntu developers could
participate in Debcamp (one week hack-together before Debconf) to work
with some Debian developers, go through Ubuntu patches, and merge the
interesting bits. This would nicely complement Ubuntu s increased presence
at Debconf: for the first time, community management team member Jorge Castro was at DebConf 10 giving a talk on
collaboration between Debian and Ubuntu.
There was also some brainstorming on how to identify packages where the
collaboration is failing. A growing number of Ubuntu revisions (identified
for example by a version like 1.0-1ubuntu62) could indicate that no
synchronization was made with Debian, but it would also identify packages
which are badly maintained on the Debian side. If Ubuntu consistently has
a newer upstream version compared to Debian, it can also indicate a
problem: maybe the person maintaining the package for Ubuntu would be better
off doing the same work in Debian directly since the maintainer is lagging or not
doing their work. Unfortunately this doesn t hold true for all packages
since many Gnome packages are newer in Ubuntu but are actively maintained
on both sides.
Few of those discussions led to concrete decisions. It seems most
proponents are reasonably satisfied with the current situation. Of course,
one can always do better and Jono Bacon is going to ensure that all
Canonical teams working on Ubuntu are aware of how to properly cooperate
with Debian. The goal is to avoid heavy package modifications without
coordination.
Conclusion
The Debian-Ubuntu relationships used to be a hot topic, but that s no
longer the case thanks to regular efforts made on both sides. Conflicts
between individuals still happen, but there are multiple places where they
can be reported and discussed (#debian-ubuntu channel, Derivatives
Front Desk at derivatives@debian.org on the
Debian side or debian@ubuntu.com on
the Ubuntu side). Documentation and infrastructure are in place to
make it easier for volunteers to do the right thing.
Despite all those process improvements, the best results still come out
when people build personal relationships by discussing what they
are doing. It often leads to tight cooperation, up to commit rights to the
source repositories. Regular contacts help build a real sense of
cooperation that no automated process can ever hope to achieve.
This article was first published in Linux Weekly News. You can get my monthly summary of the Debian/Ubuntu news, all you have to do is to click here to subscribe to my free newsletter.
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The Ubuntu Technical Board is currently conducting a review of the top ten Brainstorm issues users have raised about Ubuntu, and Matt asked me to investigate and respond to Idea #25301: Keeping the time accurate over the Internet by default.
My first reaction was "hey, that's odd - I thought we already did that?". We install the ntpdate package by default (although it's deprecated upstream in favour of other tools, but that shouldn't be important here). ntpdate is run from /etc/network/if-up.d/ntpdate, in other words every time you connect to a network, which should be acceptably frequent for most people, so it really ought to Just Work by default. But this is one of the top ten problems where users have gone to the trouble of proposing solutions on Brainstorm, so it couldn't be that simple. What was going on?
I brought up a clean virtual machine with a development version of Natty (the current Ubuntu development version, which will eventually become 11.04), and had a look in its logs: it was indeed synchronising its time from ntp.ubuntu.com, and I didn't think anything in that area had changed recently. On the other hand, I had occasionally noticed that my own laptop wasn't always synchronising its time quite right, but I'd put it down to local weirdness as my network isn't always very stable. Maybe this wasn't so local after all?
So, I started tracing through the scripts to figure out what was going on. It turned out that I had an empty /etc/ntp.conf file on my laptop. The /usr/sbin/ntpdate-debian script assumed that that meant I had a full NTP server installed (I don't), and fetched the list of servers from it; since the file was empty, it ended up synchronising time from no servers, that is, not synchronising at all. I removed the file and all was well.
That left the question of where that file came from. It didn't seem to be owned by any package; I was pretty sure I hadn't created it by hand either. I had a look through some bug reports, and soon found ntpdate 1:4.2.2.p4+dfsg-1ubuntu2 has a flawed configuration file. It turns out that time-admin (System -> Administration -> Time and Date) creates an empty /etc/ntp.conf file if you press the reload button (tooltip: "Synchronise now"), as part of an attempt to update NTP configuration. Aha!
Once I knew where the problems were, it was easy to fix them. I've uploaded the following changes, which will be in the 11.04 release:
ntp.conf files in ntpdate-debian./etc/ntp.conf file on fresh installation of the ntp package, so that it doesn't interfere with creating the normal configuration file.time-admin backend if it doesn't exist already.ntp.ubuntu.com then you'll have to change the value of NTPSERVERS in /etc/default/ntpdate. Furthermore, the time-admin interface is confusing and makes it seem as though the default is not to synchronise the time automatically; this interface is being redesigned at the moment, which should be a good opportunity to make it less confusing, and I will contact the designers to mention this problem. On the whole, though, I think that many fewer people should have this kind of problem in Ubuntu 11.04.
It's always possible that I missed some other problem that breaks automatic time synchronisation for people. Please do file a bug report if it still doesn't work for you in 11.04, or contact me directly (cjwatson at ubuntu.com).
As a first step on
the road to evaluating different configuration management systems, I set up
two VMs to test out puppet.
Puppet is conveniently packaged within Debian so client and server
installation was very simple. By default, puppet clients will look for a host
named puppet on the local network, so by naming the server sensibly the two
started talking to each other. puppetca --sign [client hostname] on the
server started the ball rolling.
My first test configuration was to add a user to the sudoers file. With
CF Engine 2, I would have achieved this by using editfiles to check for a
regular expression and insert a line if necessary. I stumbled across some
CF Engine-style definitions for puppet in a Debian Administration
article (taken originally
from puppet's own wiki, which have since been moved/deleted) and achieved it
using
append_if_no_such_line sudo:
file => "/etc/sudoers",
line => "jon ALL=(ALL) ALL"
jon ALL=(ALL) ALL, it won't match exactly and a
duplicate line will be appended, whereas with CF Engine 2 I would have checked
for something like ^jon \+ALL=(ALL) \+ALL$.
I set up my work laptop as another test node, and used puppet to install some
packages that I commonly use:
class jon-desktop
package ['icedove', 'git-core', 'vim-gnome', 'vinagre', 'build-essential',
'devscripts', 'subversion', 'git-buildpackage', 'mutt',
'offlineimap', 'ascii', 'gitk', 'chromium-browser'
]: ensure => installed
puppet on
foreign networks (such as my home network). I would have assumed that, once
the strong SSL association had been made, the client would try to connect to
the FQDN of the server. This probably isn't a serious problem in practice,
as we probably won't need to rely on nodes off-site talking to the
configuration server, but I hope that the client doesn't trust any host that
happens to answer to puppet...
I fixed this by hacking my hosts file to include an entry for puppet. I
could maintain this hack using Puppet itself, which would protect me against
stale definitions if any renumbering takes place. I could also have added a
line
server = puppet.fqdn.example.org
/etc/puppet/puppet.conf, which is a more robust way of solving the
problem.
This week I had to write a little tool that would collect input on
different channels, via socket / netcat, via a http server, .... Calls
for a parralel Design -- Maybe a good place to write something real in
Erlang. While erlang itself was really nice
to write -- I do like Prolog as well as the bunch of functional
languages -- doing networking in erlang seems a bit special, the
interfaces just aren't thin wrappers around the libc stuff.
Getting a Socket Text interface
What sounds like a easy challenge to accomplish was actually harder
than expected. All I found was some way to pass binaries representing
erlang code over a socket and evaluating it remotle. While it's nice
that such things are as easy to do as they are it doesn't help me with
my task of moving simple strings.
start() ->
ok, Listen = gen_tcp:listen(51622, [binary, packet, 0 ,
reuseaddr, true ,
active, true ]),
spawn(fun () -> accept_loop(Listen) end).
accept_loop(Listen) ->
ok, Socket = gen_tcp:accept(Listen),
accept_loop(Listen),
handle(Socket)
handle(Socket) ->
receive
tcp, Socket, Bin ->
io:format("~p~n", binary_to_list(Bin));
tcp_closed, Socket ->
Buffer
end.
spawn() at the right place. The right place is not
the handle(Socket) but the accept_loop(Listen) because the process
that called accept will receive all the tcp messages.
This last part was quite obvious after finding the documentation of
the active, _ properties for the socket. always here means that
you'll receive all data from the socket as erlang Messages, once
delivers one package and waits until it is activated again and false
requires calling a method -- this would have been possible as well
when forking handle(Socket).
The web server
Ok we also want a webserver. We do not want to run some
webapplication inside appache or so, just do some post/get and simple
pages. Erlang here provides a built-in httpd with some mod_esi
that calls some function depending on the URL used. It doesn't do
anything fancy like templating or DB backends or stuff, just taking
strings and building the http answers.
Unfortunately there are no examples around and basically noone seems
to be using this combination (apart from some hacks like mine
probably). So as I needed to get some additional information into the
handler function (a Pid to connect to some service), I, as a novice,
just couldn't find a way. Asking on IRC the solution was rather
simple: Just using erlang's process registry. For more complex stuf
gproc might prove usefull here.
Result
I guess I've got a huge step farther in programming erlang now. The
manpages are easily found by your search engine -- for python I have
to either walk through the (well structured) online documentation or
search for the right link in the search results, for erlang they're
typically first. Also
Joe Armstrong's Books
as proven usefull. The most dificult part probably is getting around
all the nice extras you can do (transfering functions over sockets et
al) and find out how to do the thing you need.
Guillermo Garron of Go2Linux enjoys a lot the People behind Debian interviews that I make. That s why he interviewed me (with somewhat similar questions) and published the result on his blog.
Click here to read the full interview. I speak of my Debian projects, of the Ubuntu-Debian relationship, and more.
The question that I would like to highlight is What s the biggest problem of Debian? . I answered this:
Our project identity is somewhat minimalistic. It evolves around the social contract and the Debian Free Software Guidelines. Both documents answer the question of what we re doing but we lack a clear answer to the question of how we re supposed to work towards our goals. It would be great if Debian could agree on some principles concerning topics like goal setting, collaboration, team work, politeness, respect. We could then advertise those and build on them while recruiting volunteers.PS: The interview also hit LinuxToday.
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A continuation of my intermittent series on Emdebian. This time covering how Emdebian changes component behaviourin Emdebian Grip.
deb http://www.emdebian.org/grip squeeze main dev debug java doc
My name is Pau and I am a software developer at Arisnova, a Spanish company specialized in Linux and Windows software development for the supervision and control (SCADA) of industrial environments.
In Debian, I am the maintainer of:
Next.