Debian News – Page 60

People behind Debian: Maximilian Attems, member of the kernel team

February 17, 2011 by Raphaël Hertzog

Maximilian, along with the other members of the Debian kernel team, has the overwhelming job of maintaining the Linux kernel in Debian. It’s one of the largest package and certainly one where dealing with bug reports is really difficult as most of them are hardware-specific, and thus difficult to reproduce.

He’s very enthusiastic and energetic, and does not fear criticizing when something doesn’t please him. You’ll see.

My questions are in bold, the rest is by Maximilian.

Who are you?

My name is Maximilian Attems. I am a theoretical physicist in my last year of PhD at the Technical University of Vienna. My main research area is the early phase of a Quark-Gluon Plasma as produced in heavy ion collisions at the LHC at CERN. I am developing simulations that take weeks on the Vienna Scientific Cluster (in the TOP 500 list). The rest of the lab is much less fancy and boils down to straight intel boxes without any binary blobs or external drivers (although lately we add radeon graphics for decent free 3D). Mathematica and Maple are the rare exceptions to the many dev tools of Debian (LaTeX, editors, git, IDE’s, Open MPI, ..) found at the institute, as those are unfortunately yet unmatched in Free Software for symbolic computations. The lab mostly runs a combination of Debian stable (testing starting from freeze) for desktops and oldstable/stable for servers. Debian is in use for more than 10 years. So people in the institute know some ups and downs of the project. Newcomers like my room neighbors are always surprised how functional a free Debian Desktop is. 🙂

What’s your biggest achievement within Debian?

Building lots and lots of kernels together with an growing uptake of the officially released linux images.

I joined the Debian kernel team shortly after Herbert Xu departed. I had been upstream Maintainer of the linux-2.6 janitor project for almost a year brewing hundreds of small cleanups with quilt in a tree named kjt for early linux-2.6. In Debian we had lots of fun in sorting out the troubles that the long 2.5 freeze had imposed: Meaning we were sitting on a huge diverging “monolithic” semi-good patchset. It was great fun to prepare 2.6.8 for Sarge with a huge team enthusiastic in shipping something real close to mainline (You have to imagine that back then you had no stable or longterm release nor any useful free tools like git. This involved passing patches around, hand editing them and seeing what the result does.)

From the Sarge install reports a common pattern emerged that the current Debian early userspace was causing lots of boot failures. This motivated me to develop an alternative using the new upstream initramfs features. So I got involved in early userspace. Thanks to large and active development team initramfs-tools got a nice ecosystem. It still tries to be as generic and flexible as possible and thus gains many nice features. Also H. Peter Anvin (hpa) gave me the official co-maintenance of klibc. klibc saw uptake and good patches from Google in the last 2 years. I am proud that the early userspace is working out fairly well these days, meaning you can shuffle discs around and see your box boot.

Later on we focused on 2.6.18 for Etch, which turned out to a be good release and picked up by several other distributions. Only very much later we would see such a “sync” again. With 2.6.26 for Lenny we got somehow unlucky as we just missed the new longterm release by one release. We also pushed for another update very late (during freeze) in the release cycle, which turned out to semi-work as too much things depend on linux-2.6.

For Squeeze 2.6.32 got picked thanks to discussions at Portland Linux Plumbers and it turned out to be a good release picked up by many distributions and external patchsets. The long-term support is going very well. Greg KH is doing a great job in collecting various needed fixes for it. Somehow we had hoped that the Squeeze freeze would start sooner and that the freeze duration would be shorter, since we were ready for a release starting from the actual freeze on. The only real big bastard on the cool 2.6.32 “sync” is Red Hat. Red Hat Enterprise 6.0 is shipping the linux-2.6 2.6.32 in obfuscated form. They released their linux-2.6 as one big tarball clashing with the spirit of the GPL. One can only mildly guess from the changelog which patches get applied. This is in sharp contrast to any previous Red Hat release and has not yet generated the sharp and snide comments in press it deserves. Red Hat should really step back and not make such stupid management moves. Next to them even the semi-maintained Oracle “Unbreakable” 2.6.32 branch looks better: It is git fetchable.

What are your plans and those of the kernel team for Debian Wheezy?

Since 2.6.32 many of the used patches landed upstream or are on the way (speakup, Kbuild Debian specific targets, ..). The proper vfs based unionfs is something we’d be looking forward. We haven’t yet picked the next upstream release we will base Wheezy on, so currently we can happily jump to the most recent ones. There are plans for better interaction with Debian Installer thanks to generating our udebs properly in linux-2.6 source itself. Also we are looking forward to using git as tool of maintenance. We’d hope that this will also allow for even better cross distribution collaboration.

Concerning early userspace I plan to release an initramfs-tools with more generic userspace for the default case and finally also a klibc only for embedded or tuning cases.

What do you like most in Debian?

For one thing I do like the 2 year release cycle. It is not too long to have completely outdated software and on the other hand it gives enough time to really see huge progress from release to release. Also at my institute the software is is recent enough without too much admin overhead. For servers the three years support are a bit short, but on the manageable side.

I do enjoy a lot the testing distribution. For my personal use it is very stable and thus I mainly run testing on my desktop and work boxes. (Occasionally mixing in things from sid for unbreaking transition or newer security fixes).

Debian is independent and not a commercial entity. I think this is its main force and even more important these days. I enjoy using the Debian platform a lot at work thus in return this motivates me to contribute to Debian itself. I also like the fact that we strive for technical correctness.

Is there some recurrent problem that hinders the progress of Debian?

The “New Maintainer process” is a strange way to discourage people to contribute to Debian. It is particularly bureaucratic and a huge waste of time both for the applicant and his manager. It should be completely thrown overboard.

One needs a more scalable approach for trust and credibility that also enhances the technical knowledge for coding and packaging of the applicant.

NM is currently set in stone as any outside critics is automatically rejected. Young and energetic people are crucial for Debian and the long-term viability of the project, this is the reason why I’d consider the “New Maintainer process” as Debian’s biggest problem.

Note from Raphaël Hertzog: I must say I do not share this point of view on the New Maintainer process, I have witnessed lots of improvements lately thanks to the addition of the Debian Maintainer status, and to the fact that a good history of contribution can easily subsume the annoying Tasks & Skills questionnaire.

Another thing I miss is professional graphics’ input both for the desktop theme and the website. I know that effort has been done there lately and it is good to see movement there, but the end result is still lacking.

Another trouble of Debian is its marketing capabilities. It should learn to better sell itself. It is the distribution users want to run and use—not the rebranded copies of itself with lock-in “sugar”. Debian is about choice and it offers plenty of it: it is a great default Desktop.

Linus Torvalds doesn’t find Debian (and/or Ubuntu) a good platform to hack on the kernel. Do you know why and what can we do about this?

The Fedora linux-2.6 receives contributions from several Red Hat employed upstream sub-Maintainers. Thus it typically carries huge patches which are not yet upstream. As a consequence eventual userland troubles get revealed quite quickly and are often seen there first. The cutting edge nature of Fedora rawhide is appealing for many developers.

The usual Debian package division of library development files and the library itself is traditionally an entry barrier for dev on Debian. Debian got pretty easily usable these days, although we could and should again improve a lot more in this sector. Personally I think that Linus hasn’t tried Debian for years.

I have the feeling that the implication of the Debian Kernel team in LKML has been on the rise. Is that true and how do you explain this?

Ben Hutchings is the Nr.1 contributor for 2.6.33. He also is top listed as author of patches on stable 2.6.32. Debian is not listed as organization as many send their linux-2.6 patches from their corporate or personal email address and thus it won’t be attributed to Debian.

There is currently no means to see how many patches get forwarded for the stable tree, but I certainly forwarded more then fifty patches. I was very happy when Greg KH personally thanked me in the 2.6.32.12 release.

In the Squeeze kernel, the firmwares have been stripped and moved into separate packages in the non-free section. What should a user do to ensure his system keeps working?

There is a debconf warning on linux-2.6 installation. It is quite clear that the free linux-2.6 can’t depend on the firmware of the non-free archive (also there is no strict dependency there technically).

On the terminal you’d also see warnings by update-initramfs on the initramfs generation for drivers included in the initramfs.

The debconf warning lists the filename(s) of the missing firmware(s). One can then “apt-cache search” for the firmware package name and install it via the non-free repository. The check runs against the current loaded modules. The match is not 100% accurate for special cases as the one where the device might be handled well by this driver without firmware, but is accurate enough to warrant the warning.

The set of virtualization technologies that the official Debian kernel supports seems to change regularly. Which of the currently available options would you recommend to users who want to build on something that will last?

KVM has been a smooth ride from day zero. It almost got included instantly upstream. The uptake it has is great as it sees both dev from Intel and AMD. Together with libvirt it’s management is easy. Also the performance of virtio is very good.

The linux containers are the thing we are looking forward for enhanced chroots in the Wheezy schedule. They are also manageable by libvirt.

Xen being the “bad outside boy” has an incredible shrinking patchset, thus is fair to expect to see it for Wheezy and beyond. For many it may come a bit late, but for old hardware without relevant CPU it is there.

Many tend to overstate the importance of the virtualization tech. I’d be much more looking forward to the better Desktop support in newer linux-2.6. The Desktop is important for linux and something that is in heavy use. The much better graphics support of the radeon and nouveau drivers:

For Nouveau in 32 with 33 drm we could only deliver a first taste meaning something better then rusty nv.
For Radeon the support for Evergreen and newer is only been shaping now.

The performance optimizations thanks to dcache scalability work and the neat automatic task-grouping for the CPU scheduler are very promising features for the usability of the linux desktop. Another nice to have feature is the online defrag of ext4 and its faster mkfs. Even cooler would be better scalability in ext4 (This side seems to have seen not enough effort lately).

Is there someone in Debian that you admire for their contributions?

Hans Peter Anvin and Ted Tso are a huge source of deep linux-2.6 knowledge and personal wisdom. I do enjoy all sorts of interactions with them.

Christoph Hellwig with Matthew Wilcox and also William Irwin for setting up the Debian kernel Team.

Several Debian leaders including the previous and the current one for their engagement, which very often happens behind the scene.

The Debian Gnome Team work is great, also the interactions have always been always easy and a pleasure.

Martin Michlmayr and previously Thiemo Seufer do an incredible job in porting Debian on funny and interesting ARM and MIPS boxes. Debian has a lot of upcoming potential on this area. I’m looking forward to other young enthusiastic people in that area.

Colin Watson is bridging Debian and Ubuntu, which is an immense task.

Michael Prokop bases on Debian an excellent recovery boot CD: http://www.grml.org. I’d be happy if any Debian Developer would work as carefully coding and working.

Thank you to Maximilian 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.

Debian 6.0 is out, Wheezy kicks off

February 6, 2011 by Raphaël Hertzog

As you probably already know, Debian released Squeeze aka Debian 6.0 this week-end. It was a really great week-end.

I saw quite a few release already, but none with so much online social activity. Alexander and Meike Schmehl live commented the release on the Debian identi.ca account and Joey Hess held his Debian Party Line.

On top of this, the team in charge of the website rolled out a new design on quite a few online services during the week-end including www.debian.org, wiki.debian.org, planet.debian.org and more.

Congratulations to all the people who made this happen (and the release team in particular). It’s great to see Debian achieve all of this.

Do you know that it’s the third time in a row that we manage to release in the 18-24 months timeframe? 3.1: June 2005 → 4.0: April 2007 → 5.0: February 2009 → 6.0: February 2011.

Yes, despite our size and the fact that we are all volunteers, we have managed to stick to a reasonable schedule for a stable distribution that is deployed on a large scale.

Wheezy kicks off

The best part of the release for us — the developers — is that wheezy is now open for development and we can work on new features for the next release. 😉

And it started quickly: according to UDD, wheezy already features 488 new source packages that are not in squeeze, 1713 updated source packages and among those 1246 are new upstream versions.

I really look forward to the upcoming projects and related discussions.

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For the curious, here are the UDD queries I used:

# Updated packages in wheezy
select count(source) from sources_uniq as su where (select version from sources_uniq where release='squeeze' and distribution='debian' and source = su.source) < su.version and release='wheezy' and distribution='debian';
# Updated with a new upstream version
select count(source) from sources_uniq as su where debversion(regexp_replace((select version from sources_uniq where release='squeeze' and distribution='debian' and source = su.source), '-.*', '')) < debversion(regexp_replace(su.version, '-.*', '')) and release='wheezy' and distribution='debian';
# New package in wheezy
select count(source) from sources_uniq as su where source not in (select source from sources_uniq where release='squeeze' and distribution='debian' and source = su.source) and release='wheezy' and distribution='debian';

People behind Debian: Mike Hommey, Firefox/Iceweasel maintainer

February 3, 2011 by Raphaël Hertzog

For as long as I have known Mike, he’s been maintaining one of the largest (and most widely used) package: Iceweasel, Debian’s default web browser. It’s effectively Mozilla’s Firefox although it has been renamed to avoid some rules enforced by Mozilla’s trademark policy. But we might see Firefox back in Debian… read on to know Mike’s plans.

His story is also very interesting in that he went from simple user to Iceweasel maintainer, and now he’s working for Mozilla Corporation. But you already knew that contributing to free software is a good way to grow skills and gain experience that are valuable on the job market, right? 😉

My questions are in bold, the rest is by Mike.

Who are you?

I am Mike Hommey. I am French, even if my name doesn’t sound so.

I have been a GNU/Linux user since 1995, using Debian since 1999, and started packaging in 2003. After a long time in the NM queue, I became a DD in 2005.

The main reason I started being actively involved is quite selfish: I wanted some things done, and I just did them. My first packages were extensions for the Mozilla Suite, the old one that directly inherited from Netscape Communicator. Later on, I wanted some of these extensions to work with the new kid on the block: Phoenix; or maybe it was already Firebird. By then, integrating extensions was a hassle, and the mozilla-browser maintainer had come up with a script that would make it easier for extension packages. So I ported that script for use with Phoenix/Firebird and sent it to the BTS.

Then Phoenix/Firebird became Firefox, and it grew a real extension manager. Except that is was entirely not suited for extensions installed by the packaging system. So I made it work better. And made a few more changes to make Firefox work better. All through patches or NMUs.

Then I became co-maintainer, then Firefox couldn’t keep its name and became Iceweasel, and, fast-forward until today, I’m now taking care of Iceweasel/Xulrunner and Iceape in stable, unstable, experimental and an external repository.

This 8 years-long story (wow, I hadn’t even realized it had been that long until I wrote it) tells you something: newcomers shouldn’t be afraid to stick their hands anywhere, even in big packages. I was only a Mozilla and Phoenix end-user when I started.

Apart from Mozilla-related packaging, I also happen to (co-)maintain some other packages in Debian, most notably webkit, though I haven’t been very active in the pkg-webkit team recently. There are several reasons for that, the main one being that there are other team members getting the job done. And I can’t say that much about the pkg-mozilla team, since there are effectively no other team members.

What’s your biggest achievement within Debian?

I am quite proud that Squeeze will be the first Debian release where Iceweasel works on all supported architectures. Previously, we only knew the package compiled on all these architectures. Starting with Squeeze, we know it passes several of the test suites coming with the source code. This ensures most of the browser is functional. It was actually far from being the case before, as it appeared when the test suites were first enabled.

I think it is very important to have properly working packages on all our supported architectures. The current evolution of hardware shows how important it still is. Who would have thought a few years back that we would see ARM or MIPS based netbooks today ?

What are your plans for Debian Wheezy?

For Debian Wheezy, I would like to improve Iceweasel/Icedove/Iceape integration with the packaging system. Something that would allow to use the apt database to find extensions or plugins, on top of the current behaviour. I also want to improve desktop integration, most notably for KDE.

Another thing I’d like to see happen is to package google breakpad independently (its source code is currently embedded in chromium and iceweasel, though not built, as far as I know), and have our Mozilla products builds be able to send their crash reports upstream. It is very important that upstream gets direct visibility over what crashes on GNU/Linux systems. It helps making them aware of issues that would otherwise probably remain unnoticed, as there are much more users using distributions packages than upstream tarballs. And not all Debian users report crashes to the BTS. I know at least Fedora and SuSE are already doing it.

More importantly, I want to avoid the sad situation we got with Squeeze, where we’re going to release a 18 months old Iceweasel. We got there for a combination of reasons, one being that I was preparing for a freeze in December 2009 and focusing on getting 3.5 in shape instead of the then upcoming 3.6.

The result was that we didn’t get 3.6 packages before upstream released 3.6.3 in April 2010. By then it was too late, considering the uncertainty of the release schedule, to update reverse dependencies and get 3.6 ready for Squeeze.

Things are different for 4.0. I’m already getting ahead of things, and while reverse dependencies haven’t been taken care of, all beta releases have been made available through http://mozilla.debian.net/, usually within hours after upstream release (sometimes even a few hours before official announcement, but always after availability on ftp.mozilla.org). A great share of our patches were also pushed upstream.

Several things made that possible:

I’m now closely following upstream trunk
I’m starting to prepare packages when candidate builds are distributed upstream, which usually happens a few days ahead for betas, and more than a week ahead for stable releases.
I automated part of the package building process, and have a beefy build machine. I’m getting near being able to provide nightly builds of upstream trunk.

There will be a couple major upstream releases until Wheezy comes along, and I want to make them available early in unstable, even if that means breaking reverse dependencies until they are fixed.

Finally, I would like to get other people involved, starting with the Icedove maintainer. Volunteers are very much welcome, for any kind of involvement: bug triaging, documentation (which we are deeply lacking), testing, code… People interested can contact the pkg-mozilla team list. As the Debian packaging gets less time consuming, I should be able to spend more time mentoring, which should help.

If you could spend all your time on Debian, what would you work on?

I actually have been working almost full time on Debian for a few months during a more-or-less purposeful unemployment period. That’s when I attempted to add an alert popup when Iceweasel or extensions are upgraded (which was eventually removed because not working very effectively). That’s when I worked on Iceweasel 3.6 and the first 4.0 betas. That’s when I pushed more than 70 patches upstream, and got upstream commit access.

I know for a fact that keeping up with upstream and answering bug reports is already time consuming, and time comes in finite quantity. Working full time on Debian allows to do more than that, as I’ve been able to experience first hand. Unfortunately, that doesn’t help pay the bills, so it would be best if time could be shared with other persons. Like, actual members in the pkg-mozilla team. 😉

Anyways, if I were to work full time on Debian again, I’d like to do more than packaging, and help improve some of our infrastructure, most notably the buildd network, to grow some automated way to get packages built on all or some of our architectures. Call that PPA if you want, though I don’t think we need something exactly like PPA.

We sure do have porter boxes, but there is a huge overhead to get packages built there: you need to first try, then see you lack build dependencies, then wait for admins to install them, then come back and launch your build, and finally come back again much later to see how it went. And that’s when it goes smoothly. Repeat for each architecture.

It’s already cumbersome when it’s a small package, so imagine when it’s Iceweasel. I’d like to be able to push a (signed) .dsc somewhere, say I want it built on that and that architecture, and get binary packages and logs back. It could then be up to developers to distribute them, or not. Sometimes, you’re just interested in test suite results.

Another related wish would be a way to access build trees of failed builds, possibly on the buildd where it failed.

What’s the biggest problem of Debian?

Lack of contributors, lack of contributors, and… lack of contributors.

It can sound weird to say that in a community of 1000+ people. But the sad reality is that we’ve seen, repeatedly, calls for help in various places from various understaffed teams (most often of effectively one member) for years. So there is obviously a problem getting people to invest time in these teams either on the long term, or at all.

I know this is not a very significant metric, but it already should say a lot: I wouldn’t be surprised if more than 2/3 of the number of source lines of code in Debian come from less than 5% of the number of packages in the archive, and see less than 5% of the DD/DM population involved. If someone feels like doing the actual math, I’m curious to know how far I’m from reality, and in what direction.

We also lack manpower to be able to make our release development smoother. In a perfect world where manpower is not a scarce resource, we should work on $release+1 when $release is being frozen. Said otherwise, we should have been able to start working on Wheezy in August 2010, or even earlier.

You’ve been working for Mozilla Corporation for a few months. How does the work look like and what are you working on?

I am actually not working full time for MoCo; I am only contracting for 4 days a week. That was a request I made to keep having enough spare time for Debian or other activities. I am working from home, and am pretty much free about when I work, as long as I work long enough. I take advantage of this freedom and the saved commuting time to live a healthier life by doing some sports in the daytime (which also happens to be cheaper).

I mostly work with Taras Glek and other people on various aspects of Firefox startup performance. This involves pretty interesting low-level stuff, in which I actually got involved before being contracted. This work has nothing to do with packaging Iceweasel, though I can have a few opportunities to do things somehow related.

You told in your blog that you were discussing with Mozilla how Debian could use the Firefox trademark. Can you tell us a bit about the progress you made?

I have got an informal approval of the patches we are applying to the Iceweasel 4.0 beta packages. There are a few concerns about using the system cairo library, and the embedded copy of libpng needs to be used to have support for the animated PNGs that are used in the user interface and that are required in Firefox’ feature-set. Other than that, there are pretty much no objection on the technical side.

We managed to get to some common ground as to how to manage stable updates and more generally, changes to our packages, but I’m still waiting for an actual agreement draft. While I, as the maintainer, am fine with the way it should look according to my discussions with the people involved at Mozilla, I’ll seek review from my fellow Debian Developers when I’ll have something to show.

I haven’t decided yet how this will reflect on the Debian packages, though. For example, would Iceweasel stay? But I do hope Wheezy will get Firefox back.

Is there someone in Debian that you admire for their contributions?

Not someone, but all past, present and future release team members. This is a team that receives a lot of critics (and I indirectly gave one a few paragraphs ago), yet manages to keep doing an amazing job and its members are very committed to their task. I admire their dedication.

Thank you to Mike 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.

Debian is eating its own dog food more than ever

January 24, 2011 by Raphaël Hertzog

In its “Fast distributions and slow servers” article, Joe ‘Zonker’ Brockmeier explains the difficulties that Fedora has to use its own distribution on their infrastructure and echoes some questions they faced:

Why wouldn’t a Linux distribution project wish to showcase the distribution by hosting its infrastructure using its own system?

I completely share the underlying assumption. Eating its own dog food is very important if you want to build a Linux distribution and claim with some confidence that it’s of quality and usable.

Debian does quite well nowadays in that respect.

There were times where the mailing list server was using Qmail (non-free at that time, and thus not part of Debian) but that’s long gone. We have also seen our build infrastructure relying on software that was not public and not packaged in Debian, but that also is history.

The Debian System Administration team (DSA) maintains more than 140 servers running Debian. They mostly run the stable version of Debian but a few test machines are already running Squeeze since a few months (qa.debian.org for example). The Debian admins want to ensure that the next stable release of Debian still has everything they need and that the software they use still work as expected.

Big kudos to the DSA team for this choice! I hope we’ll be able to continue to live up to those standards for a long time to come.

PS: If you want to learn more about the setup that the DSA team uses, head to dsa.debian.org. You’ll find all their repositories and some of their internal documentation.

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Wheezy kicks off

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