Search Results: "cas"

6 November 2020

Louis-Philippe V ronneau: Book Review: Working in Public by Nadia Eghbal

I have a lot of respect for Nadia Eghbal, partly because I can't help to be jealous of her work on the economics of Free Software1. If you are not already familiar with Eghbal, she is the author of Roads and Bridges: The Unseen Labor Behind Our Digital Infrastructure, a great technical report published for the Ford Foundation in 2016. You may also have caught her excellent keynote at LCA 2017, entitled Consider the Maintainer. Her latest book, Working in Public: The Making and Maintenance of Open Source Software, published by Stripe Press a few months ago, is a great read and if this topic interests you, I highly recommend it. The book itself is simply gorgeous; bright orange, textured hardcover binding, thick paper, wonderful typesetting it has everything to please. Well, nearly everything. Sadly, it is only available on Amazon, exclusively in the United States. A real let down for a book on Free and Open Source Software. The book is divided in five chapters, namely:
  1. Github as a Platform
  2. The Structure of an Open Source Project
  3. Roles, Incentives and Relationships
  4. The Work Required by Software
  5. Managing the Costs of Production
A picture of the book cover Contrary to what I was expecting, the book feels more like an extension of the LCA keynote I previously mentioned than Roads and Bridges. Indeed, as made apparent by the following quote, Eghbal doesn't believe funding to be the primary problem of FOSS anymore:
We still don't have a common understanding about who's doing the work, why they do it, and what work needs to be done. Only when we understand the underlying behavioral dynamics of open source today, and how it differs from its early origins, can we figure out where money fits in. Otherwise, we're just flinging wet paper towels at a brick wall, hoping that something sticks. p.184
That is to say, the behavior of maintainers and the challenges they face not the eternal money problem is the real topic of this book. And it feels refreshing. When was the last time you read something on the economics of Free Software without it being mostly about what licences projects should pick and how business models can be tacked on them? I certainly can't. To be clear, I'm not sure I agree with Eghbal on this. Her having worked at Github for a few years and having interviewed mostly people in the Ruby on Rails and Javascript communities certainly shows in the form of a strong selection bias. As she herself admits, this is a book on how software on Github is produced. As much as this choice irks me (the Free Software community certainly cannot be reduced to Github), this exercise had the merit of forcing me to look at my own selection biases. As such, reading Working in Public did to me something I wasn't expecting it to do: it broke my Free Software echo chamber. Although I consider myself very familiar with the world of Free and Open Source Software, I now understand my somewhat ill-advised contempt for certain programming languages mostly JS skewed my understanding of what FOSS in 2020 really is. My Free Software world very much revolves around Debian, a project with a strong and opinionated view of Free Software, rooted in a historical and political understanding of the term. This, Eghbal argues, is not the case for a large swat of developers anymore. They are The Github Generation, people attached to Github as a platform first and foremost, and who feel "Open Source" is just a convenient way to make things. Although I could intellectualise this, before reading the book, I didn't really grok how communities akin to npm have been reshaping the modern FOSS ecosystem and how different they are from Debian itself. To be honest, I am not sure I like this tangent and it is certainly part of the reason why I had a tendency to dismiss it as a fringe movement I could safely ignore. Thanks to Nadia Eghbal, I come out of this reading more humble and certainly reminded that FOSS' heterogeneity is real and should not be idly dismissed. This book is rich in content and although I could go on (my personal notes clock-in at around 2000 words and I certainly disagree with a number of things), I'll stop here for now. Go and grab a copy already!

  1. She insists on using the term open source, but I won't :)

4 November 2020

Christian Kastner: qemu-sbuild-utils 0.1: sbuild with QEMU

qemu-sbuild-utils, which were recently accepted into unstable, are a collection of scripts that wrap standard features of sbuild, autopkgtest-build-qemu and vmdb2 to provide a trivial interface for creating and using QEMU-based environments for package building:
  • qemu-sbuild-create creates VM images
  • qemu-sbuild-update is to VM images what sbuild-update is to chroots
  • qemu-sbuild wraps sbuild, adding all necessary (and some useful) options for autopkgtest mode.
Here's a simple two-line example for creating an image, and then using it to build a package:
$ sudo qemu-sbuild-create -o simple.img unstable http://deb.debian.org/debian

$ qemu-sbuild --image simple.img -d unstable [sbuild-options] FOO.dsc
That's it. Both qemu-sbuild-create and qemu-sbuild automate certain things, but also accept a number of options. For example, qemu-sbuild-create can install additional packages either from one of the APT sources, or .deb packages from the local filesystem. qemu-sbuild will pass on every option it does not consume itself to sbuild, so it should mostly work as a drop-in replacement for it (see the Limitations section below for where it doesn't). The created images can also be used for running autopkgtest itself, of course.
Advantages Excellent isolation. One can go nuts in an environment, change or even break things, and the VM can always simply be reset, or rolled back to an earlier state. Snapshots are just terrific for so many reasons. With KVM acceleration and a fast local APT cache, builds are really fast. There's an overhead of a few seconds for booting the VM on my end, but that overhead is negligible in comparison to the overall build time. On the upside, with everything being memory-backed, even massive dependency installations are lightning fast. With the parameters of the target environment being configurable, it's possible to test builds in various settings (for example: single-core vs. multi-core, or with memory constraints). Technically, it should be possible to emulate, on one host, any other guest architecture (even if emulation might be slow because of missing hardware acceleration). This would present an attractive alternative to (possibly distant and/or slow) porter boxes. However, support for that in qemu-sbuild-utils is not quite there yet.
Limitations The utilities are currently only available on the amd64 architecture, for building packages in amd64 and i386 VMs. There are plans to support arm64 in the near future. qemu-sbuild-create needs root, for the debootstrap stage. I'm looking into ways around this (by extending vmdb2). In any case, image updating and package building do not need privileges. autopkgtest mode does not yet support interactivity, so one cannot drop into a shell with --build-failed-commands, for example. The easy workaround is to connect to the VM with SSH. For this, the image must contain the openssh-server package.
Alternatives I looked at qemubuilder, but had troubles getting it to work. In any case, the autopkgtest chroot mode of sbuild seemed far more powerful and useful to me. vectis looks incredibly promising, but I had already written qemu-sbuild-utils by the time I stumbled over it, and as my current setup works well for me for now and is simple enough to maintain, I decided to polish and publish it. I'm also looking into Docker- and other namespace-based isolation solutions (of which there are many), which I think are the way forward for the majority of packages (those that aren't too close to the kernel and/or hardware). Rather than relying on the kernel for isolation, KVM-based solutions like Amazon's Firecracker and QEMU's microvm machine type provide minimal VMs with almost no boot overhead. Firecracker, for example, claims less than 125ms from launch to /sbin/init. Investigating these is a medium-term project for me.
Why not schroot? I have a strong aversion towards chroot-based build environments. The concept is archaic. Far superior software- and/or hardware-based technologies for process isolation have emerged in the past two decades, and I think it is high time to leave chroot-based solutions behind.
Acknowledgments These utilities are just high-level abstractions. All the heavy lifting is done by sbuild, autopkgtest, and vmdb2.

3 November 2020

Martin-Éric Racine: GRUB fine-tuning

A couple of years ago, I moved into a new flat that comes with RJ45 sockets wired for 10 Gigabit (but currently offering 1 Gigabit) Ethernet.This also meant changing the settings on my router box for my new ISP.I took this opportunity to review my router's other settings too. I'll be blogging about these over the next few posts. GRUB fine-tuning One thing that had been annoying me ever since Debian migrated to systemd as /sbin/init is that boot message verbosity hasn't been the same. Previously, the cmdline option quiet merely suppressed the kernel's output to the bootscreen, but left the daemon startup messages alone. Not anymore. Nowadays, quiet produces a blank screen. After some googling, I found the solution to that: GRUB_CMDLINE_LINUX_DEFAULT="noquiet loglevel=5" The former restores daemon startup messages, while the later makes the kernel output only significant notices or more serious messages. On most of my hosts, it mostly reports inconsistencies in the ACPI configuration of the BIOS. Another setting I find useful is a reboot delay in case a kernel panic happens: GRUB_CMDLINE_LINUX="panic=15" This gives me enough time to snap a picture of the screen output to attach to the bug report that will follow.

2 November 2020

Dirk Eddelbuettel: RcppSimdJson 0.1.2: New Upstream, New Utilities

A new RcppSimdJson release arrived on CRAN late yesterday bringing along the one recently updated simdjson release 0.6.0. RcppSimdJson wraps the fantastic and genuinely impressive simdjson library by Daniel Lemire and collaborators. Via very clever algorithmic engineering to obtain largely branch-free code, coupled with modern C++ and newer compiler instructions, it results in parsing gigabytes of JSON parsed per second which is quite mindboggling. The best-case performance is faster than CPU speed as use of parallel SIMD instructions and careful branch avoidance can lead to less than one cpu cycle per byte parsed; see the video of the talk by Daniel Lemire at QCon (also voted best talk). Other than the upstream update, Brendan added some new utilities to check for valid utf-8 or json format, and to minify json plus a small workaround for a clang-9 bug we encountered. We can confirm Daniel s statement on ridiculously fast utf-8 validattion. It is so cool to work with amazing tools. The NEWS entry follows.

Changes in version 0.1.3 (2020-11-01)
  • Added URLs to DESCRIPTION (Dirk closing #50).
  • Upgraded to simdjson 0.6.0 (Dirk in #52).
  • New policy option to always convert integers to int64_t (Brendan in #55 closing #54).
  • Added workaround for odd clang-9 bug (Brendan in #57).
  • New utility functions is_valid_utf8(), is_valid_json() and fminify() (Brendan in #58).

Courtesy of my CRANberries, there is also a diffstat report for this release. For questions, suggestions, or issues please use the issue tracker at the GitHub repo. If you like this or other open-source work I do, you can now sponsor me at GitHub. For the first year, GitHub will match your contributions.

This post by Dirk Eddelbuettel originated on his Thinking inside the box blog. Please report excessive re-aggregation in third-party for-profit settings.

29 October 2020

Ulrike Uhlig: Better handling emergencies

We all know these situations when we receive an email asking Can you check the design of X, I need a reply by tonight. Or an instant message: My website went down, can you check? Another email: I canceled a plan at the hosting company, can you restore my website as fast as possible? A phone call: The TLS certificate didn t get updated, and now we can t access service Y. Yet another email: Our super important medical advice website is suddenly being censored in country Z, can you help? Everyone knows those messages that have URGENT in capital letters in the email subject. It might be that some of them really are urgent. Others are the written signs of someone having a hard time properly planning their own work and passing their delays on to someone who comes later in the creation or production chain. And others again come from people who are overworked and try to delegate some of their tasks to a friendly soul who is likely to help.

How emergencies create more emergencies In the past, my first reflex when I received an urgent request was to start rushing into solutions. This happened partly out of empathy, partly because I like to be challenged into solving problems, and I m fairly good at that. This has proven to be unsustainable, and here is why.

Emergencies create unplanned work The first issue is that emergencies create a lot of unplanned work. Which in turn means not getting other, scheduled, things done. This can create a backlog, end up in working late, or working on weekends.

Emergencies can create a permanent state of exception Unplanned work can also create a lot of frustration, out of the feeling of not getting the things done that one planned to do. We might even get a feeling of being nonautonomous (in German I would say fremdbestimmt, which roughly translates to being directed by others ). On the long term, this can generate unsustainable situations: higher work loads, and burnout. When working in a team of several people, A might have to take over the work of B because B has not enough capacities. Then A gets overloaded in turn, and C and D have to take over A s work. Suddenly the team is stuck in a permanent state of exception. This state of exception will produce more backlog. The team might start to deprioritize social issues over getting technical things done. They might not be able to recruit new people anymore because they have no capacity left to onboard newcomers.

One emergency can result in a variety of emergencies for many people The second issue produced by urgent requests is that if I cannot solve the initial emergency by myself, I might try to involve colleagues, other people who are skilled in the area, or people who work in another relevant organization to help with this. Suddenly, the initial emergency has become my emergency as well as the emergency of a whole bunch of other people.

A sidenote about working with friends This might be less of an issue in a classical work setup than in a situation in which a bunch of freelancers work together, or in setups in which work and friendships are intertwined. This is a problem, because the boundaries between friend and worker role, and the expectations that go along with these roles, can get easily confused. If a colleague asks me to help with task X, I might say no; if a friend asks, I might be less likely to say no.

What I learnt about handling emergencies I came up with some guidelines that help me to better handle emergencies.

Plan for unplanned work It doesn t matter and it doesn t help to distinguish if urgent requests are legitimate or if they come from people who have not done their homework on time. What matters is to make one s weekly todo list sustainable. After reading Making work visible by Domenica de Grandis, I understood the need to add free slots for unplanned work into one s weekly schedule. Slots for unplanned work can take up to 25% of the total work time!

Take time to make plans Now that there are some free slots to handle emergencies, one can take some time to think when an urgent request comes in. A German saying proposes to wait and have some tea ( abwarten und Tee trinken ). I think this is actually really good advice, and works for any non-obvious problem. Sit down and let the situation sink in. Have a tea, take a shower, go for a walk. It s never that urgent. Really, never. If possible, one can talk about the issue with another person, rubberduck style. Then one can make a plan on how to address the emergency properly, it could be that the solution is easier than at first thought.

Affirming boundaries: Saying no Is the emergency that I m asked to solve really my problem? Or is someone trying to involve me because they know I m likely to help? Take a deep breath and think about it. No? It s not my job, not my role? I have no time for this right now? I don t want to do it? Maybe I m not even paid for it? A colleague is pushing my boundaries to get some task on their own todo list done? Then I might want to say no. I can t help with this. or I can help you in two weeks. I don t need to give a reason. No. is a sentence. And: Saying no doesn t make me an arse.

Affirming boundaries: Clearly defining one s role Clearly defining one s role is something that is often overlooked. In many discussions I have with friends it appears that this is a major cause of overwork and underpayment. Lots of people are skilled, intelligent, and curious, and easily get challenged into putting on their super hero dress. But they re certainly not the only person that can help even if an urgent request makes them think that at first. To clearly define our role, we need to make clear which part of the job is our work, and which part needs to be done by other people. We should stop trying to accomodate people and their requests to the detriment of our own sanity. You re a language interpreter and are being asked to mediate a bi-lingual conflict between the people you are interpreting for? It s not your job. You re the graphic designer for a poster, but the text you ve been given is not good enough? Send back a recommendation to change the text; don t do these changes yourself: it s not your job. But you can and want to do this yourself and it would make your client s life easier? Then ask them to get paid for the extra time, and make sure to renegotiate your deadline!

Affirming boundaries: Defining expectations Along with our role, we need to define expectations: in which timeframe am I willing to do the job? Under which contract, which agreement, which conditions? For which payment? People who work in a salary office job generally do have a work contract in which their role and the expectations that come with this role are clearly defined. Nevertheless, I hear from friends that their superiors regularly try to make them do tasks that are not part of their role definition. So, here too, role and expectations sometimes need to be renegotiated, and the boundaries of these roles need to be clearly affirmed.

Random conclusive thoughts If you ve read until here, you might have experienced similar things. Or, on the contrary, maybe you re already good at communicating your boundaries and people around you have learnt to respect them? Congratulations. In any case, for improving one s own approach to such requests, it can be useful to find out which inner dynamics are at play when we interact with other people. Additionally, it can be useful to understand the differences between Asker and Guesser culture:
when an Asker meets a Guesser, unpleasantness results. An Asker won t think it s rude to request two weeks in your spare room, but a Guess culture person will hear it as presumptuous and resent the agony involved in saying no. Your boss, asking for a project to be finished early, may be an overdemanding boor or just an Asker, who s assuming you might decline. If you re a Guesser, you ll hear it as an expectation.
Askers should also be aware that there might be Guessers in their team. It can help to define clear guidelines about making requests (when do I expect an answer, under which budget/contract/responsibility does the request fall, what other task can be put aside to handle the urgent task?) Last, but not least, Making work visible has a lot of other proposals on how to visibilize and then deal with unplanned work.

Norbert Preining: Deleting many files from an S3 bucket

So we found ourselves in the need to delete a considerable amount of files (around 500000, amounting to 1.6T) from an S3 bucket. With the list of files in hand my first shot was calling
aws s3 rm s3://BUCKET/FILE
for each file. That wasn t the best idea I have to say, since first of all, it makes 500000 requests, and then it takes a looong time. And this command does not allow to pass in multiple files. Fortunately there is aws s3api delete-objects which takes a json input and can delete multiple files:
aws 3api delete-objects --bucket BUCKET --delete ' "Objects": [   "Key" : "FILE1"  ,   "Key" : "FILE2"  ... ] '
That did help, and with a bit of magic from bash (mapfile which can read in lines from stdin in batches) and jq, at the end it was a business of some 20min or so:
cat files-to-be-deleted    while mapfile -t -n 500 ary && (($ #ary[@] )); do
        objdef=$(printf '%s\n' "$ ary[@] "   jq -nR ' Objects: (reduce inputs as $line ([]; . + [ "Key":$line ])) ')
        aws s3api --no-cli-pager  delete-objects --bucket BUCKET --delete "$objdef"
done
This reads 500 files a time, and reformats it using jq into the proper json format: reduce inputs is a jq filter that iterates over the input lines and does a map/reduce step. In this case we use an empty array as start and add new key/filename pairs on the go. Finally, the whole bunch is send to AWS with the above API call. Puuuh, 500000 files and 1.6T less, in 20min.

24 October 2020

Jelmer Vernooij: Debian Janitor: Hosters used by Debian packages

The Debian Janitor is an automated system that commits fixes for (minor) issues in Debian packages that can be fixed by software. It gradually started proposing merges in early December. The first set of changes sent out ran lintian-brush on sid packages maintained in Git. This post is part of a series about the progress of the Janitor. The Janitor knows how to talk to different hosting platforms. For each hosting platform, it needs to support the platform- specific API for creating and managing merge proposals. For each hoster it also needs to have credentials. At the moment, it supports the GitHub API, Launchpad API and GitLab API. Both GitHub and Launchpad have only a single instance; the GitLab instances it supports are gitlab.com and salsa.debian.org. This provides coverage for the vast majority of Debian packages that can be accessed using Git. More than 75% of all packages are available on salsa - although in some cases, the Vcs-Git header has not yet been updated. Of the other 25%, the majority either does not declare where it is hosted using a Vcs-* header (10.5%), or have not yet migrated from alioth to another hosting platform (9.7%). A further 2.3% are hosted somewhere on GitHub (2%), Launchpad (0.18%) or GitLab.com (0.15%), in many cases in the same repository as the upstream code. The remaining 1.6% are hosted on many other hosts, primarily people s personal servers (which usually don t have an API for creating pull requests). Packages per hoster

Outdated Vcs-* headers It is possible that the 20% of packages that do not have a Vcs-* header or have a Vcs header that say there on alioth are actually hosted elsewhere. However, it is hard to know where they are until a version with an updated Vcs-Git header is uploaded. The Janitor primarily relies on vcswatch to find the correct locations of repositories. vcswatch looks at Vcs-* headers but has its own heuristics as well. For about 2,000 packages (6%) that still have Vcs-* headers that point to alioth, vcswatch successfully finds their new home on salsa.
Merge Proposals by Hoster These proportions are also visible in the number of pull requests created by the Janitor on various hosters. The vast majority so far has been created on Salsa.
Hoster Open Merged & Applied Closed
github.com921685
gitlab.com1230
code.launchpad.net24511
salsa.debian.org1,3605,657126
Merge Proposal statistics In this graph, Open means that the pull request has been created but likely nobody has looked at it yet. Merged means that the pull request has been marked as merged on the hoster, and applied means that the changes have ended up in the packaging branch but via a different route (e.g. cherry-picked or manually applied). Closed means that the pull request was closed without the changes being incorporated. Note that this excludes ~5,600 direct pushes, all of which were to salsa-hosted repositories. See also:

For more information about the Janitor's lintian-fixes efforts, see the landing page.

23 October 2020

Birger Schacht: An Analysis of 5 Million OpenPGP Keys

In July I finished my Bachelor s Degree in IT Security at the University of Applied Sciences in St. Poelten. During the studies I did some elective courses, one of which was about Data Analysis using Python, Pandas and Jupyter Notebooks. I found it very interesting to do calculations on different data sets and to visualize them. Towards the end of the Bachelor I had to find a topic for my Bachelor Thesis and as a long time user of OpenPGP I thought it would be interesting to do an analysis of the collection of OpenPGP keys that are available on the keyservers of the SKS keyserver network. So in June 2019 I fetched a copy of one of the key dumps of the one of the keyservers (some keyserver publish these copies of their key database so people who want to join the SKS keyserver network can do an initial import). At that time the copy of the key database contained 5,499,675 keys and was around 12GB. Using the hockeypuck keyserver software I imported the keys into an PostgreSQL database. Hockeypuck uses a table called keys to store the keys and in there the column doc stores the OpenPGP keys in JSON format (always with a data field containing the original unparsed data). For the thesis I split the analysis in three parts, first looking at the Public Key packets, then analysing the User ID packets and finally studying the Signature Packets. To analyse the respective packets I used SQL to export the data to CSV files and then used the pandas read_csv method to create a dataframe of the values. In a couple of cases I did some parsing before converting to a DataFrame to make the analysis step faster. The parsing was done using the pgpdump python library. Together with my advisor I decided to submit the thesis for a journal, so we revised and compressed the whole paper and the outcome was now

PUBLISHED in the Journal of Wireless Mobile Networks, Ubiquitous Computing, and Dependable Applications (JoWUA). I think the work gives some valuable insight in the development of the use of OpenPGP in the last 30 years. Looking at the public key packets we were able to compare the different public key algorithms and for example visualize how DSA was the most used algorithm until around 2010 when it was replaced by RSA. When looking at the less used algorithms a trend towards ECC based crytography is visible. What we also noticed was an increase of RSA keys with algorithm ID 3 (RSA Sign-Only), which are deprecated. When we took a deeper look at those keys we realized that most of those keys used a specific User ID string in the User ID packets which allowed us to attribute those keys to two software projects both using the Bouncy Castle Java Cryptographic API (resp. the Spongy Castle version for Android). We also stumbled over a tutorial on how to create RSA keys with Bouncycastle which also describes how to create RSA keys with code that produces RSA Sign-Only keys. In one of those projects, this was then fixed. By looking at the User ID packets we did some statistics about the most used email providers used by OpenPGP users. One domain stood out, because it is not the domain of an email provider: tellfinder.com is a domain used in around 45,000 keys. Tellfinder is a Big Data analysis software and the UID of all but two of those keys is TellFinder Page Archiver- Signing Key <support@tellfinder.com>. We also looked at the comments used in OpenPGP User ID fields. In 2013 Daniel Kahn Gillmor published a blog post titled OpenPGP User ID Comments considered harmful in which he pointed out that most of the comments in the User ID field of OpenPGP keys are duplicating information that is already present somewhere in the User ID or the key itself. In our dataset 3,133 comments were exactly the same as the name, 3,346 were the same as the domain and 18,246 comments were similar to the local part of the email address Last but not least we looked at the signature subpackets and the development of some of the preferences (Preferred Symmetric Algorithm, Preferred Hash Algorithm) that are being published using signature packets. Analysing this huge dataset of cryptographic keys of the last 20 to 30 years was very interesting and I learned a lot about the history of PGP resp. OpenPGP and the evolution of cryptography overall. I think it would be interesting to look at even more properties of OpenPGP keys and I also think it would be valuable for the OpenPGP ecosystem if these kinds analysis could be done regularly. An approach like Tor Metrics could lead to interesting findings and could also help to back decisions regarding future developments of the OpenPGP standard.

Molly de Blanc: Endorsements

Transparency is essential to trusting a technology. Through transparency we can understand what we re using and build trust. When we know what is actually going on, what processes are occurring and how it is made, we are able to decide whether interacting with it is something we actually want, and we re able to trust it and use it with confidence. This transparency could mean many things, though it most frequently refers to the technology itself: the code or, in the case of hardware, the designs. We could also apply it to the overall architecture of a system. We could think about the decision making, practices, and policies of whomever is designing and/or making the technology. These are all valuable in some of the same ways, including that they allow us to make a conscious choice about what we are supporting. When we choose to use a piece of technology, we are supporting those who produce it. This could be because we are directly paying for it, however our support is not limited to direct financial contributions. In some cases this is because of things hidden within a technology: tracking mechanisms or backdoors that could allow companies or governments access to what we re doing. When creating different types of files on a computer, these files can contain metadata that says what software was used to make it. This is an implicit endorsement, and you can also explicitly endorse a technology by talking about that or how you use it. In this, you have a right (not just a duty) to be aware of what you re supporting. This includes, for example, organizational practices and whether a given company relies on abusive labor policies, indentured servitude, or slave labor.
Endorsements inspire others to choose a piece of technology. Most of my technology is something I investigate purely for functionality, and the pieces I investigate are based on what people I know use. The people I trust in these cases are more inclined than most to do this kind of research, to perform technical interrogations, and to be aware of what producers of technology are up to. This is how technology spreads and becomes common or the standard choice. In one sense, we all have the responsibility (one I am shirking) to investigate our technologies before we choose them. However, we must acknowledge that not everyone has the resources for this the time, the skills, the knowledge, and therein endorsements become even more important to recognize. Those producing a technology have the responsibility of making all of these angles something one could investigate. Understanding cannot only be the realm of experts. It should not require an extensive background in research and investigative journalism to find out whether a company punishes employees who try to unionize or pay non-living wages. Instead, these must be easy activities to carry out. It should be standard for a company (or other technology producer) to be open and share with people using their technology what makes them function. It should be considered shameful and shady to not do so. Not only does this empower those making choices about what technologies to use, but it empowers others down the line, who rely on those choices. It also respects the people involved in the processes of making these technologies. By acknowledging their role in bringing our tools to life, we are respecting their labor. By holding companies accountable for their practices and policies, we are respecting their lives.

21 October 2020

Reproducible Builds: Supporter spotlight: Civil Infrastructure Platform

The Reproducible Builds project depends on our many projects, supporters and sponsors. We rely on their financial support, but they are also valued ambassadors who spread the word about the Reproducible Builds project and the work that we do. This is the first installment in a series featuring the projects, companies and individuals who support the Reproducible Builds project. If you are a supporter of the Reproducible Builds project (of whatever size) and would like to be featured here, please let get in touch with us at contact@reproducible-builds.org. However, we are kicking off this series by featuring Urs Gleim and Yoshi Kobayashi of the Civil Infrastructure Platform (CIP) project.
Chris Lamb: Hi Urs and Yoshi, great to meet you. How might you relate the importance of the Civil Infrastructure Platform to a user who is non-technical? A: The Civil Infrastructure Platform (CIP) project is focused on establishing an open source base layer of industrial-grade software that acts as building blocks in civil infrastructure projects. End-users of this critical code include systems for electric power generation and energy distribution, oil and gas, water and wastewater, healthcare, communications, transportation, and community management. These systems deliver essential services, provide shelter, and support social interactions and economic development. They are society s lifelines, and CIP aims to contribute to and support these important pillars of modern society.
Chris: We have entered an age where our civilisations have become reliant on technology to keep us alive. Does the CIP believe that the software that underlies our own safety (and the safety of our loved ones) receives enough scrutiny today? A: For companies developing systems running our infrastructure and keeping our factories working, it is part of their business to ensure the availability, uptime, and security of these very systems. However, software complexity continues to increase, and the efforts spent on those systems is now exploding. What is missing is a common way of achieving this through refining the same tools, and cooperating on the hardening and maintenance of standard components such as the Linux operating system.
Chris: How does the Reproducible Builds effort help the Civil Infrastructure Platform achieve its goals? A: Reproducibility helps a great deal in software maintenance. We have a number of use-cases that should have long-term support of more than 10 years. During this period, we encounter issues that need to be fixed in the original source code. But before we make changes to the source code, we need to check whether it is actually the original source code or not. If we can reproduce exactly the same binary from the source code even after 10 years, we can start to invest time and energy into making these fixes.
Chris: Can you give us a brief history of the Civil Infrastructure Platform? Are there any specific success stories that the CIP is particularly proud of? A: The CIP Project formed in 2016 as a project hosted by Linux Foundation. It was launched out of necessity to establish an open source framework and the subsequent software foundation delivers services for civil infrastructure and economic development on a global scale. Some key milestones we have achieved as a project include our collaboration with Debian, where we are helping with the Debian Long Term Support (LTS) initiative, which aims to extend the lifetime of all Debian stable releases to at least 5 years. This is critical because most control systems for transportation, power plants, healthcare and telecommunications run on Debian-based embedded systems. In addition, CIP is focused on IEC 62443, a standards-based approach to counter security vulnerabilities in industrial automation and control systems. Our belief is that this work will help mitigate the risk of cyber attacks, but in order to deal with evolving attacks of this kind, all of the layers that make up these complex systems (such as system services and component functions, in addition to the countless operational layers) must be kept secure. For this reason, the IEC 62443 series is attracting attention as the de facto cyber-security standard.
Chris: The Civil Infrastructure Platform project comprises a number of project members from different industries, with stakeholders across multiple countries and continents. How does working together with a broad group of interests help in your effectiveness and efficiency? A: Although the members have different products, they share the requirements and issues when developing sustainable products. In the end, we are driven by common goals. For the project members, working internationally is simply daily business. We see this as an advantage over regional or efforts that focus on narrower domains or markets.
Chris: The Civil Infrastructure Platform supports a number of other existing projects and initiatives in the open source world too. How much do you feel being a part of the broader free software community helps you achieve your aims? A: Collaboration with other projects is an essential part of how CIP operates we want to enable commonly-used software components. It would not make sense to re-invent solutions that are already established and widely used in product development. To this end, we have an upstream first policy which means that, if existing projects need to be modified to our needs or are already working on issues that we also need, we work directly with them.
Chris: Open source software in desktop or user-facing contexts receives a significant amount of publicity in the media. However, how do you see the future of free software from an industrial-oriented context? A: Open source software has already become an essential part of the industry and civil infrastructure, and the importance of open source software there is still increasing. Without open source software, we cannot achieve, run and maintain future complex systems, such as smart cities and other key pieces of civil infrastructure.
Chris: If someone wanted to know more about the Civil Infrastructure Platform (or even to get involved) where should they go to look? A: We have many avenues to participate and learn more! We have a website, a wiki and you can even follow us on Twitter.

For more about the Reproducible Builds project, please see our website at reproducible-builds.org. If you are interested in ensuring the ongoing security of the software that underpins our civilisation and wish to sponsor the Reproducible Builds project, please reach out to the project by emailing contact@reproducible-builds.org.

20 October 2020

Steve Kemp: Offsite-monitoring, from my desktop.

For the past few years I've had a bunch of virtual machines hosting websites, services, and servers. Of course I want them to be available - especially since I charge people money to access at some of them (for example my dns-hosting service) - and that means I want to know when they're not. The way I've gone about this is to have a bunch of machines running stuff, and then dedicate an entirely separate machine solely for monitoring and alerting. Sure you can run local monitoring, testing that services are available, the root-disk isn't full, and that kind of thing. But only by testing externally can you see if the machine is actually available to end-users, customers, or friends.
A local-agent might decide "I'm fine", but if the hosting-company goes dark due to a fibre cut you're screwed.
I've been hosting my services with Hetzner (cloud) recently, and their service is generally pretty good. Unfortunately I've started to see an increasing number of false-alarms. I'd have a server in Germany, with the monitoring machine in Helsinki (coincidentally where I live!). For the past month I've started to get pinged with a failure every three/four days on average, "service down - dns failed", or "service down - timeout". When the notice would wake me up I'd go check and it would be fine, it was a very transient failure. To be honest the reason for this is my monitoring is just too damn aggressive, I like to be alerted immediately in case something is wrong. That means if a single test fails I get an alert, as rather than only if a test failed for something more reasonable like three+ consecutive failures. I'm experimenting with monitoring in a less aggressive fashion, from my home desktop. Since my monitoring tool is a single self-contained golang binary, and it is already packaged as a docker-based container deployment was trivial. I did a little work writing an agent to receive failure-notices, and ping me via telegram - instead of the previous approach where I had an online status-page which I could view via my mobile, and alerts via pushover. So far it looks good. I've tweaked the monitoring to setup a timeout of 15 seconds, instead of 5, and I've configured it to only alert me if there is an outage which lasts for >= 2 consecutive failures. I guess the TLDR is I now do offsite monitoring .. from my house, rather than from a different region. The only real reason to write this post was mostly to say that the process of writing a trivial "notify me" gateway to interface with telegram was nice and straightforward, and to remind myself that transient failures are way more common than we expect. I'll leave things alone for a moment, but it was a fun experiment. I'll keep the two systems in parallel for a while, but I guess I can already predict the outcome:

19 October 2020

Louis-Philippe V ronneau: Musings on long-term software support and economic incentives

Although I still read a lot, during my college sophomore years my reading habits shifted from novels to more academic works. Indeed, reading dry textbooks and economic papers for classes often kept me from reading anything else substantial. Nowadays, I tend to binge read novels: I won't touch a book for months on end, and suddenly, I'll read 10 novels back to back1. At the start of a novel binge, I always follow the same ritual: I take out my e-reader from its storage box, marvel at the fact the battery is still pretty full, turn on the WiFi and check if there are OS updates. And I have to admit, Kobo Inc. (now Rakuten Kobo) has done a stellar job of keeping my e-reader up to date. I've owned this model (a Kobo Aura 1st generation) for 7 years now and I'm still running the latest version of Kobo's Linux-based OS. Having recently had trouble updating my Nexus 5 (also manufactured 7 years ago) to Android 102, I asked myself:
Why is my e-reader still getting regular OS updates, while Google stopped issuing security patches for my smartphone four years ago?
To try to answer this, let us turn to economic incentives theory. Although not the be-all and end-all some think it is3, incentives theory is not a bad tool to analyse this particular problem. Executives at Google most likely followed a very business-centric logic when they decided to drop support for the Nexus 5. Likewise, Rakuten Kobo's decision to continue updating older devices certainly had very little to do with ethics or loyalty to their user base. So, what are the incentives that keep Kobo updating devices and why are they different than smartphone manufacturers'? A portrait of the current long-term software support offerings for smartphones and e-readers Before delving deeper in economic theory, let's talk data. I'll be focusing on 2 brands of e-readers, Amazon's Kindle and Rakuten's Kobo. Although the e-reader market is highly segmented and differs a lot based on geography, Amazon was in 2015 the clear worldwide leader with 53% of the worldwide e-reader sales, followed by Rakuten Kobo at 13%4. On the smartphone side, I'll be differentiating between Apple's iPhones and Android devices, taking Google as the barometer for that ecosystem. As mentioned below, Google is sadly the leader in long-term Android software support. Rakuten Kobo According to their website and to this Wikipedia table, the only e-readers Kobo has deprecated are the original Kobo eReader and the Kobo WiFi N289, both released in 2010. This makes their oldest still supported device the Kobo Touch, released in 2011. In my book, that's a pretty good track record. Long-term software support does not seem to be advertised or to be a clear selling point in their marketing. Amazon According to their website, Amazon has dropped support for all 8 devices produced before the Kindle Paperwhite 2nd generation, first sold in 2013. To put things in perspective, the first Kindle came out in 2007, 3 years before Kobo started selling devices. Like Rakuten Kobo, Amazon does not make promises of long-term software support as part of their marketing. Apple Apple has a very clear software support policy for all their devices:
Owners of iPhone, iPad, iPod or Mac products may obtain a service and parts from Apple or Apple service providers for five years after the product is no longer sold or longer, where required by law.
This means in the worst-case scenario of buying an iPhone model just as it is discontinued, one would get a minimum of 5 years of software support. Android Google's policy for their Android devices is to provide software support for 3 years after the launch date. If you buy a Pixel device just before the new one launches, you could theoretically only get 2 years of support. In 2018, Google decided OEMs would have to provide security updates for at least 2 years after launch, threatening not to license Google Apps and the Play Store if they didn't comply. A question of cost structure From the previous section, we can conclude that in general, e-readers seem to be supported longer than smartphones, and that Apple does a better job than Android OEMs, providing support for about twice as long. Even Fairphone, who's entire business is to build phones designed to last and to be repaired was not able to keep the Fairphone 1 (2013) updated for more than a couple years and seems to be struggling to keep the Fairphone 2 (2015) running an up to date version of Android. Anyone who has ever worked in IT will tell you: maintaining software over time is hard work and hard work by specialised workers is expensive. Most commercial electronic devices are sold and developed by for-profit enterprises and software support all comes down to a question of cost structure. If companies like Google or Fairphone are to be expected to provide long-term support for the devices they manufacture, they have to be able to fund their work somehow. In a perfect world, people would be paying for the cost of said long-term support, as it would likely be cheaper then buying new devices every few years and would certainly be better for the planet. Problem is, manufacturers aren't making them pay for it. Economists call this type of problem externalities: things that should be part of the cost of a good, but aren't for one a reason or another. A classic example of an externality is pollution. Clearly pollution is bad and leads to horrendous consequences, like climate change. Sane people agree we should drastically cut our greenhouse gas emissions, and yet, we aren't. Neo-classical economic theory argues the way to fix externalities like pollution is to internalise these costs, in other words, to make people pay for the "real price" of the goods they buy. In the case of climate change and pollution, neo-classical economic theory is plain wrong (spoiler alert: it often is), but this is where band-aids like the carbon tax comes from. Still, coming back to long-term software support, let's see what would happen if we were to try to internalise software maintenance costs. We can do this multiple ways. 1 - Include the price of software maintenance in the cost of the device This is the choice Fairphone makes. This might somewhat work out for them since they are a very small company, but it cannot scale for the following reasons:
  1. This strategy relies on you giving your money to an enterprise now, and trusting them to "Do the right thing" years later. As the years go by, they will eventually look at their books, see how much ongoing maintenance is costing them, drop support for the device, apologise and move on. That is to say, enterprises have a clear economic incentive to promise long-term support and not deliver. One could argue a company's reputation would suffer from this kind of behaviour. Maybe sometime it does, but most often people forget. Political promises are a great example of this.
  2. Enterprises go bankrupt all the time. Even if company X promises 15 years of software support for their devices, if they cease to exist, your device will stop getting updates. The internet is full of stories of IoT devices getting bricked when the parent company goes bankrupt and their servers disappear. This is related to point number 1: to some degree, you have a disincentive to pay for long-term support in advance, as the future is uncertain and there are chances you won't get the support you paid for.
  3. Selling your devices at a higher price to cover maintenance costs does not necessarily mean you will make more money overall raising more money to fund maintenance costs being the goal here. To a certain point, smartphone models are substitute goods and prices higher than market prices will tend to drive consumers to buy cheaper ones. There is thus a disincentive to include the price of software maintenance in the cost of the device.
  4. People tend to be bad at rationalising the total cost of ownership over a long period of time. Economists call this phenomenon hyperbolic discounting. In our case, it means people are far more likely to buy a 500$ phone each 3 years than a 1000$ phone each 10 years. Again, this means OEMs have a clear disincentive to include the price of long-term software maintenance in their devices.
Clearly, life is more complex than how I portrayed it: enterprises are not perfect rational agents, altruism exists, not all enterprises aim solely for profit maximisation, etc. Still, in a capitalist economy, enterprises wanting to charge for software maintenance upfront have to overcome these hurdles one way or another if they want to avoid failing. 2 - The subscription model Another way companies can try to internalise support costs is to rely on a subscription-based revenue model. This has multiple advantages over the previous option, mainly:
  1. It does not affect the initial purchase price of the device, making it easier to sell them at a competitive price.
  2. It provides a stable source of income, something that is very valuable to enterprises, as it reduces overall risks. This in return creates an incentive to continue providing software support as long as people are paying.
If this model is so interesting from an economic incentives point of view, why isn't any smartphone manufacturer offering that kind of program? The answer is, they are, but not explicitly5. Apple and Google can fund part of their smartphone software support via the 30% cut they take out of their respective app stores. A report from Sensor Tower shows that in 2019, Apple made an estimated US$ 16 billion from the App Store, while Google raked in US$ 9 billion from the Google Play Store. Although the Fortune 500 ranking tells us this respectively is "only" 5.6% and 6.5% of their gross annual revenue for 2019, the profit margins in this category are certainly higher than any of their other products. This means Google and Apple have an important incentive to keep your device updated for some time: if your device works well and is updated, you are more likely to keep buying apps from their store. When software support for a device stops, there is a risk paying customers will buy a competitor device and leave their ecosystem. This also explains why OEMs who don't own app stores tend not to provide software support for very long periods of time. Most of them only make money when you buy a new phone. Providing long-term software support thus becomes a disincentive, as it directly reduces their sale revenues. Same goes for Kindles and Kobos: the longer your device works, the more money they make with their electronic book stores. In my opinion, it's likely Amazon and Rakuten Kobo produce quarterly cost-benefit reports to decide when to drop support for older devices, based on ongoing support costs and the recurring revenues these devices bring in. Rakuten Kobo is also in a more precarious situation than Amazon is: considering Amazon's very important market share, if your device stops getting new updates, there is a greater chance people will replace their old Kobo with a Kindle. Again, they have an important economic incentive to keep devices running as long as they are profitable. Can Free Software fix this? Yes and no. Free Software certainly isn't a magic wand one can wave to make everything better, but does provide major advantages in terms of security, user freedom and sometimes costs. The last piece of the puzzle explaining why Rakuten Kobo's software support is better than Google's is technological choices. Smartphones are incredibly complex devices and have become the main computing platform of many. Similar to the web, there is a race for features and complexity that tends to create bloat and make older devices slow and painful to use. On the other hand, e-readers are simpler devices built for a single task: display electronic books. Control over the platform is also a key aspect of the cost structure of providing software updates. Whereas Apple controls both the software and hardware side of iPhones, Android is a sad mess of drivers and SoCs, all providing different levels of support over time6. If you take a look at the platforms the Kindle and Kobo are built on, you'll quickly see they both use Freescale I.MX SoCs. These processors are well known for their excellent upstream support in the Linux kernel and their relative longevity, chips being produced for either 10 or 15 years. This in turn makes updates much easier and less expensive to provide. So clearly, open architectures, free drivers and open hardware helps tremendously, but aren't enough on their own. One of the lessons we must learn from the (amazing) LineageOS project is how lack of funding hurts everyone. If there is no one to do the volunteer work required to maintain a version of LOS for your device, it won't be supported. Worse, when purchasing a new device, users cannot know in advance how many years of LOS support they will get. This makes buying new devices a frustrating hit-and-miss experience. If you are lucky, you will get many years of support. Otherwise, you risk your device becoming an expensive insecure paperweight. So how do we fix this? Anyone with a brain understands throwing away perfectly good devices each 2 years is not sustainable. Government regulations enforcing a minimum support life would be a step in the right direction, but at the end of the day, Capitalism is to blame. Like the aforementioned carbon tax, band-aid solutions can make things somewhat better, but won't fix our current economic system's underlying problems. For now though, I'll leave fixing the problem of Capitalism to someone else.

  1. My most recent novel binge has been focused on re-reading the Dune franchise. I first read the 6 novels written by Frank Herbert when I was 13 years old and only had vague and pleasant memories of his work. Great stuff.
  2. I'm back on LineageOS! Nice folks released an unofficial LOS 17.1 port for the Nexus 5 last January and have kept it updated since then. If you are to use it, I would also recommend updating TWRP to this version specifically patched for the Nexus 5.
  3. Very few serious economists actually believe neo-classical rational agent theory is a satisfactory explanation of human behavior. In my opinion, it's merely a (mostly flawed) lens to try to interpret certain behaviors, a tool amongst others that needs to be used carefully, preferably as part of a pluralism of approaches.
  4. Good data on the e-reader market is hard to come by and is mainly produced by specialised market research companies selling their findings at very high prices. Those particular statistics come from a MarketWatch analysis.
  5. If they were to tell people: You need to pay us 5$/month if you want to receive software updates, I'm sure most people would not pay. Would you?
  6. Coming back to Fairphones, if they had so much problems providing an Android 9 build for the Fairphone 2, it's because Qualcomm never provided Android 7+ support for the Snapdragon 801 SoC it uses.

18 October 2020

Iustin Pop: Serendipity

To start off, let me say it again: I hate light pollution. I really, really hate it. I love the night sky where you look up and see thousands of stars, and constellations besides Ursa Major. As somebody said once, You haven t lived until you ve seen your shadow by the light of the Milky Way . But, ahem, I live in a large city, and despite my attempts using star trackers, special filters, etc. you simply can t escape it. So, whenever we go on vacation in the mountains, I m trying to think if I can do a bit of astro-photography (not that I m good at it). Which bring me to our recent vacation up in the mountains. I was looking forward to it, until in the week before, when the weather prognosis was switching between snow, rain and overcast for the entire week. No actual day or night with clear skies, so I didn t take a tripod, I didn t take a wide lens, and put night photography out of my mind. Vacation itself was good, especially the quietness of the place, so I usually went to be early-ish and didn t look outside. The weather was as forecasted - no new snow (but there was enough up in the mountains), but heavy clouds all the time, and the sun only showed itself for a few minutes at a time. One night I was up a bit longer than usual, working on the laptop and being very annoyed by a buzzing sound. At first I thought maybe I was imagining it, but from time to time it was stopping briefly, so it was a real noise; I started hunting for the source. Not my laptop, not the fridge, not the TV but it was getting stronger near the window. I open the door to the balcony, and bam! Very loud noise, from the hotel nearby, where at midnight the pool was being cleaned. I look at the people doing the work, trying to estimate how long it ll be until they finish, but it was looking like a long time. Fortunately with the door closed the noise was not bad enough to impact my sleep, so I debate getting angry or just resigned, and since it was late, I just sigh, roll my eyes not metaphorically, but actually roll my eyes and look up, and I can t believe my eyes. Completely clear sky, no trace of clouds anywhere, and stars. Lots of starts. I sit there, looking at the sky and enjoying the view, and I think to myself that it won t look that nice on the camera, for sure. Especially without a real trip, and without a fast lens. Nevertheless, I grab my camera and just for kicks take one handheld picture. To my surprise (and almost disbelief), blurry pixels aside, the photo does look like what I was seeing, so I grab my tiny tripod that I carried along, and (with only a 24-70 zoom lens), grab a photo. And another, and another and then I realise that if I can make the composition work, and find a good shutter speed, this can turn out a good picture. I didn t have a remote release, the tripod was not very stable and it cannot point the camera upwards (it s basically an emergency tripod), so it was quite sub-optimal; still, I try multiple shots (different compositions, different shutter speeds); they look on the camera screen and on the phone pretty good, so just for safety I take a few more, and, very happy, go to bed. Coming back from vacation, on the large monitor, it turns out that the first 28 out of the 30 pictures were either blurry or not well focused (as I was focusing manually), and the 29th was almost OK but still not very good. Only the last, the really last picture, was technically good and also composition-wise OK. Luck? Foresight? Don t know, but it was worth deleting 28 pictures to get this one. One of my best night shots, despite being so unprepared
Stars! Lots of stars! And mountains Stars! Lots of stars! And mountains
Of course, compared to other people s pictures, this is not special. But for me, it will be a keepsake of how a real night sky should look like. If you want to zoom in, higher resolution on flickr. Technically, the challenges for the picture were two-fold: Next time when travelling by car, I ll surely take a proper tripod Until next time, clear and dark skies

15 October 2020

Jelmer Vernooij: Debian Janitor: How to Contribute Lintian-Brush Fixers

The Debian Janitor is an automated system that commits fixes for (minor) issues in Debian packages that can be fixed by software. It gradually started proposing merges in early December. The first set of changes sent out ran lintian-brush on sid packages maintained in Git. This post is part of a series about the progress of the Janitor. lintian-brush can currently fix about 150 different issues that lintian can report, but that's still a small fraction of the more than thousand different types of issue that lintian can detect. If you're interested in contributing a fixer script to lintian-brush, there is now a guide that describes all steps of the process:

  1. how to identify lintian tags that are good candidates for automated fixing
  2. creating test cases
  3. writing the actual fixer

For more information about the Janitor's lintian-fixes efforts, see the landing page.

Gunnar Wolf: I am who I am and that's all that I am

Mexico was one of the first countries in the world to set up a national population registry in the late 1850s, as part of the church-state separation that was for long years one of the national sources of pride. Forty four years ago, when I was born, keeping track of the population was still mostly a manual task. When my parents registered me, my data was stored in page 161 of book 22, year 1976, of the 20th Civil Registration office in Mexico City. Faithful to the legal tradition, everything is handwritten and specified in full. Because, why would they write 1976.04.27 (or even 27 de abril de 1976) when they could spell out d a veintisiete de abril de mil novecientos setenta y seis? Numbers seem to appear only for addresses. So, the State had record of a child being born, and we knew where to look if we came to need this information. But, many years later, a very sensible tecnification happened: all records (after a certain date, I guess) were digitized. Great news! I can now get my birth certificate without moving from my desk, paying a quite reasonable fee (~US$4). What s there not to like? Digitally certified and all! So great! But But Oh, there s a problem. Of course Making sense of the handwriting as you can see is somewhat prone to failure. And I cannot blame anybody for failing to understand the details of my record. So, my mother s first family name is Iszaevich. It was digitized as Iszaerich. Fortunately, they do acknowledge some errors could have made it into the process, and there is a process to report and correct errors. What s there not to like? Oh That they do their best to emulate a public office using online tools. I followed some links in that link to get the address to contact and yesterday night sent them the needed documents. Quite immediately, I got an answer that I must share with the world: Yes, the mailing contact is in the @gmail.com domain. I could care about them not using a @ .gob.mx address, but I ll let it slip. The mail I got says (uppercase and all):
GOOD EVENING,
WE INFORM YOU THAT THE RECEPTION OF E-MAILS FOR REQUESTING
CORRECTIONS IN CERTIFICATES IS ONLY ACTIVE MONDAY THROUGH FRIDAY,
8:00 TO 15:00.
*IN CASE YOU SENT A MAIL OUTSIDE THE WORKING HOURS, IT WILL BE
AUTOMATICALLY DELETED BY THE SERVER*
CORDIAL GREETINGS,
I would only be half-surprised if they were paying the salary of somebody to spend the wee hours of the night receiving and deleting mails from their GMail account.

14 October 2020

Michael Stapelberg: distri: a Linux distribution to research fast package management

Over the last year or so I have worked on a research linux distribution in my spare time. It s not a distribution for researchers (like Scientific Linux), but my personal playground project to research linux distribution development, i.e. try out fresh ideas. This article focuses on the package format and its advantages, but there is more to distri, which I will cover in upcoming blog posts.

Motivation I was a Debian Developer for the 7 years from 2012 to 2019, but using the distribution often left me frustrated, ultimately resulting in me winding down my Debian work. Frequently, I was noticing a large gap between the actual speed of an operation (e.g. doing an update) and the possible speed based on back of the envelope calculations. I wrote more about this in my blog post Package managers are slow . To me, this observation means that either there is potential to optimize the package manager itself (e.g. apt), or what the system does is just too complex. While I remember seeing some low-hanging fruit , through my work on distri, I wanted to explore whether all the complexity we currently have in Linux distributions such as Debian or Fedora is inherent to the problem space. I have completed enough of the experiment to conclude that the complexity is not inherent: I can build a Linux distribution for general-enough purposes which is much less complex than existing ones. Those were low-hanging fruit from a user perspective. I m not saying that fixing them is easy in the technical sense; I know too little about apt s code base to make such a statement.

Key idea: packages are images, not archives One key idea is to switch from using archives to using images for package contents. Common package managers such as dpkg(1) use tar(1) archives with various compression algorithms. distri uses SquashFS images, a comparatively simple file system image format that I happen to be familiar with from my work on the gokrazy Raspberry Pi 3 Go platform. This idea is not novel: AppImage and snappy also use images, but only for individual, self-contained applications. distri however uses images for distribution packages with dependencies. In particular, there is no duplication of shared libraries in distri. A nice side effect of using read-only image files is that applications are immutable and can hence not be broken by accidental (or malicious!) modification.

Key idea: separate hierarchies Package contents are made available under a fully-qualified path. E.g., all files provided by package zsh-amd64-5.6.2-3 are available under /ro/zsh-amd64-5.6.2-3. The mountpoint /ro stands for read-only, which is short yet descriptive. Perhaps surprisingly, building software with custom prefix values of e.g. /ro/zsh-amd64-5.6.2-3 is widely supported, thanks to:
  1. Linux distributions, which build software with prefix set to /usr, whereas FreeBSD (and the autotools default), which build with prefix set to /usr/local.
  2. Enthusiast users in corporate or research environments, who install software into their home directories.
Because using a custom prefix is a common scenario, upstream awareness for prefix-correctness is generally high, and the rarely required patch will be quickly accepted.

Key idea: exchange directories Software packages often exchange data by placing or locating files in well-known directories. Here are just a few examples:
  • gcc(1) locates the libusb(3) headers via /usr/include
  • man(1) locates the nginx(1) manpage via /usr/share/man.
  • zsh(1) locates executable programs via PATH components such as /bin
In distri, these locations are called exchange directories and are provided via FUSE in /ro. Exchange directories come in two different flavors:
  1. global. The exchange directory, e.g. /ro/share, provides the union of the share sub directory of all packages in the package store.
    Global exchange directories are largely used for compatibility, see below.
  2. per-package. Useful for tight coupling: e.g. irssi(1) does not provide any ABI guarantees, so plugins such as irssi-robustirc can declare that they want e.g. /ro/irssi-amd64-1.1.1-1/out/lib/irssi/modules to be a per-package exchange directory and contain files from their lib/irssi/modules.

Search paths sometimes need to be fixed Programs which use exchange directories sometimes use search paths to access multiple exchange directories. In fact, the examples above were taken from gcc(1) s INCLUDEPATH, man(1) s MANPATH and zsh(1) s PATH. These are prominent ones, but more examples are easy to find: zsh(1) loads completion functions from its FPATH. Some search path values are derived from --datadir=/ro/share and require no further attention, but others might derive from e.g. --prefix=/ro/zsh-amd64-5.6.2-3/out and need to be pointed to an exchange directory via a specific command line flag.

FHS compatibility Global exchange directories are used to make distri provide enough of the Filesystem Hierarchy Standard (FHS) that third-party software largely just works. This includes a C development environment. I successfully ran a few programs from their binary packages such as Google Chrome, Spotify, or Microsoft s Visual Studio Code.

Fast package manager I previously wrote about how Linux distribution package managers are too slow. distri s package manager is extremely fast. Its main bottleneck is typically the network link, even at high speed links (I tested with a 100 Gbps link). Its speed comes largely from an architecture which allows the package manager to do less work. Specifically:
  1. Package images can be added atomically to the package store, so we can safely skip fsync(2) . Corruption will be cleaned up automatically, and durability is not important: if an interactive installation is interrupted, the user can just repeat it, as it will be fresh on their mind.
  2. Because all packages are co-installable thanks to separate hierarchies, there are no conflicts at the package store level, and no dependency resolution (an optimization problem requiring SAT solving) is required at all.
    In exchange directories, we resolve conflicts by selecting the package with the highest monotonically increasing distri revision number.
  3. distri proves that we can build a useful Linux distribution entirely without hooks and triggers. Not having to serialize hook execution allows us to download packages into the package store with maximum concurrency.
  4. Because we are using images instead of archives, we do not need to unpack anything. This means installing a package is really just writing its package image and metadata to the package store. Sequential writes are typically the fastest kind of storage usage pattern.
Fast installation also make other use-cases more bearable, such as creating disk images, be it for testing them in qemu(1) , booting them on real hardware from a USB drive, or for cloud providers such as Google Cloud.

Fast package builder Contrary to how distribution package builders are usually implemented, the distri package builder does not actually install any packages into the build environment. Instead, distri makes available a filtered view of the package store (only declared dependencies are available) at /ro in the build environment. This means that even for large dependency trees, setting up a build environment happens in a fraction of a second! Such a low latency really makes a difference in how comfortable it is to iterate on distribution packages.

Package stores In distri, package images are installed from a remote package store into the local system package store /roimg, which backs the /ro mount. A package store is implemented as a directory of package images and their associated metadata files. You can easily make available a package store by using distri export. To provide a mirror for your local network, you can periodically distri update from the package store you want to mirror, and then distri export your local copy. Special tooling (e.g. debmirror in Debian) is not required because distri install is atomic (and update uses install). Producing derivatives is easy: just add your own packages to a copy of the package store. The package store is intentionally kept simple to manage and distribute. Its files could be exchanged via peer-to-peer file systems, or synchronized from an offline medium.

distri s first release distri works well enough to demonstrate the ideas explained above. I have branched this state into branch jackherer, distri s first release code name. This way, I can keep experimenting in the distri repository without breaking your installation. From the branch contents, our autobuilder creates:
  1. disk images, which
  2. a package repository. Installations can pick up new packages with distri update.
  3. documentation for the release.
The project website can be found at https://distr1.org. The website is just the README for now, but we can improve that later. The repository can be found at https://github.com/distr1/distri

Project outlook Right now, distri is mainly a vehicle for my spare-time Linux distribution research. I don t recommend anyone use distri for anything but research, and there are no medium-term plans of that changing. At the very least, please contact me before basing anything serious on distri so that we can talk about limitations and expectations. I expect the distri project to live for as long as I have blog posts to publish, and we ll see what happens afterwards. Note that this is a hobby for me: I will continue to explore, at my own pace, parts that I find interesting. My hope is that established distributions might get a useful idea or two from distri.

There s more to come: subscribe to the distri feed I don t want to make this post too long, but there is much more! Please subscribe to the following URL in your feed reader to get all posts about distri: https://michael.stapelberg.ch/posts/tags/distri/feed.xml Next in my queue are articles about hermetic packages and good package maintainer experience (including declarative packaging).

Feedback or questions? I d love to discuss these ideas in case you re interested! Please send feedback to the distri mailing list so that everyone can participate!

12 October 2020

Markus Koschany: My Free Software Activities in September 2020

Welcome to gambaru.de. Here is my monthly report (+ the first week in October) that covers what I have been doing for Debian. If you re interested in Java, Games and LTS topics, this might be interesting for you. Debian Games
warzone2100
Debian Java
pdfsam
Misc Debian LTS This was my 55. month as a paid contributor and I have been paid to work 31,75 hours on Debian LTS, a project started by Rapha l Hertzog. In that time I did the following: ELTS Extended Long Term Support (ELTS) is a project led by Freexian to further extend the lifetime of Debian releases. It is not an official Debian project but all Debian users benefit from it without cost. The current ELTS release is Debian 8 Jessie . This was my 28. month and I have been paid to work 15 hours on ELTS. Thanks for reading and see you next time.

Jonathan Dowland: Type design

I wanted to share Type design issue I hit recently with Striot. Within StrIoT you define a stream-processing program, which is a series of inter-connected operators, in terms of a trio of graph types: For some recent work I needed to define some additional properties for the operators: properties that would be used in a M/M/1 model (Jackson network) to represent the program do some cost modelling with. Initially we supplied this additional information in completely separate instances of types: e.g. lists of tuples, the first of a pair representing a vertexID, etc. This was mostly fine for totally novel code, but where I had existing code paths that operated in terms of Graph StreamVertex and now needed access to these parameters, it would have meant refactoring a lot of code. So instead, I added these properties directly to the types above. Some properties are appropriate for all node types, e.g. mean average service time. In that case, I added the parameter to the StreamVertex type:
data StreamVertex = StreamVertex
      vertexId   :: Int
     
    , serviceTime:: Double
     
Other parameters were only applicable to certain node types. Mean average arrival rate, for example., is only valid for Source node types; selectivity is appropriate only for filter types. So, I added these to the StreamOperator type:
data StreamOperator = Map
                      Filter Double -- selectivity
                     
                      Source Double -- arrival rate
                     
This works pretty well, and most of the code paths that already exist did not need to be updated in order for the model parameters to pass through to where they are needed. But it was not a perfect solution, because I now had to modify some other, unrelated code to account for the type changes. Mostly this was test code: where I'd defined instances of Graph StreamVertex to test something unrelated to the modelling work, I now had to add filter selectivities and source arrival rates. This was tedious but mostly solved with automatically with some editor macros. One area though, that was a problem, was equality checks and pattern matching. Before this change, I had a few areas of code like this
if Source == operator (head (vertexList sg))
 
if a /= b then  -- where a and b are instances of StreamOperator
I had to replace them with little helper routines like
cmpOps :: StreamOperator -> StreamOperator -> Bool
cmpOps (Filter _) (Filter _) = True
cmpOps (FilterAcc _) (FilterAcc _) = True
cmpOps x y = x == y
A similar problem was where I needed to synthesize a Filter, and I didn't care about the selectivity, indeed, it was meaningless for the way I was using the type. I have a higher-level function that handles "hoisting" an Operator through a Merge: So, before, you have some operator occurring after a merge operation, and afterwards, you have several instances of the operator on all of the input streams prior to the Merge. Invoking it now looks like this
filterMerge = pushOp (Filter 0)
It works, the "0" is completely ignored, but the fact I have to provide it, and it's unneeded, and there is no sensible value for it, is a bit annoying. I think there's some interesting things to consider here about Type design, especially when you have some aspects of a "thing" which are relevant only in some contexts and not others.

10 October 2020

William (Bill) Blough: sudo reboot


Benjy: The best-laid plans of mice... Arthur: And men. Frankie: What? Arthur: Best-laid plans of mice and men. Benjy: What have men got to do with it? -- The Hitchhiker's Guide to the Galaxy TV series
Last year, my intent had been to post monthy updates with details of the F/LOSS contributions I had made during the previous month. I wanted to do this as a way to summarize and reflect on what I had done, and also to hopefully motivate me to do more. Fast forward, and it's been over a year since my last blog post. So much for those plans. I won't go into specific detail about the F/LOSS contributions I've made in the past year. This isn't meant to be a "catch-up" post, per se. It's more of an acknowledgement that I didn't do what I set out to do, as well as something of a reset to enable me to continue blogging (or not) as I see fit. So, to summarize those contributions: All in all, I'm pretty happy with the contributions I've made in the past year. Historically, my F/LOSS activity had been somewhat sporadic, sometimes with months passing in between contributions. But looking through my notes from the past year, it appears that I made contributions every single month, with no skipped months. Of course, I would have liked to have done more, but I consider the improvement in consistency to be a solid win. As for the blog, well... Judging by the most recent year-long gap (as well as the gaps before that), I'm not likely to start regularly writing posts anytime soon. But then again, if sporadic F/LOSS contribtutions can turn into regular F/LOSS contributions, then maybe sporadic blog posts can turn into regular blog posts, too. Time will tell.

9 October 2020

Yves-Alexis Perez: Airplane pilot

So, a bit more thank 18 months ago, I started a new adventure. After a few flights with a friend of mine in a Robin DR400 and Jodel aircrafts, I enlisted in a local flight club at the Lognes airfield (LFPL), and started a Pilot Private License training. A PPL is an international flight license for non commercial operations. Associated with a qualification like the SEP (Single Engine Piston), it enables you to fly basically anywhere in the world (or at least anywhere where French is spoken by the air traffic controllers) with passengers, under Visual Flight Rules (VFR).

A bit like with cars, training has two parts, theoretical and practical, both validated in a test. You don't have to pass the theoretical test before starting the practical training, and it's actually recommended to do both in parallel, especially since nowadays most of the theoretical training is done online (you still have to do 10h of in-person courses before taking the test).
So in March 2019 I started both trainings. Theoretical training is divided in various domains, like regulations, flight mechanics, meteorology, human factors etc. and you can obviously train in parallel. Practical is more sequential and starts with basic flight training (turns, climbs, descents), then take-off, then landing configuration, then landing itself. All of that obviously with a flight instructor sitting next to you (you're on the left seat but the FI is the pilot in command ). You then start doing circuit patterns, meaning you take off, do a circuit around the airfield, then land on the runway you just took off. Usually you actually don't do a complete landing but rather touch and go, and do it again in order to have more and more landing training.

Once you know how to take-off, do a pattern and land when everything is OK, you start practicing (still with your flight instructor aboard) various failures: especially engine failures at take off, but also flaps failure and stuff like that, all that while still doing patterns and practicing landings. At one point, the flight instructor deems you ready: he exits the plane, and you start your first solo flight: engine tests, take off, one pattern, landing.

For me practical training was done in an Aquila AT-01/A210, which is a small 2-seater. It's really light (it can actually be used as an ultralight), empty weight is a bit above 500kg and max weight is 750. It doesn't go really fast (it cruises at around 100 knots, 185 km/h) but it's nice to fly. As it's really lightweight the wind really shakes it though and it can be a bit hard to land because it really glides very well (with a lift-to-drag ratio at 14). I tried to fly a lot in the beginning, so the basic flight training was done in about 6 months and 23 flight hours. At that point my instructor stepped out of the plane and I did my first solo flight. Everything actually went just fine, because we did repeat a lot before that, so it wasn't even that scary. I guess I will remember my whole life, as people said, but it was pretty uneventful, although the controller did scold me a little because when taxiing back to the parking I misunderstood the instructions and didn't stop where asked (no runway incursion though).

After the first solo flight, you keep practicing patterns and solo flights every once in a while, and start doing cross-country flights: you're not restricted to the local airfields (LFPL, LFAI, LFPK) but start planning trips to more remote airports, about 30-40 minutes away (for me it was Moret/LFPU, Troyes/LFQB, Pontoise/LFPT). Cross country flights requires you to plan the route (draw it on the map, and write a navigation log so you know what to do when in flight), but also check the weather, relevant information, especially NOTAMs - Notice To Air Men (I hope someone rename those Notice to Air Crews at one point), estimate the fuel needed etc. For me, flight preparation time was between once and twice the flight time. Early flight preparation is completed on the day by last-minute checks, especially for weather. During the briefing (with the flight instructor at first, but for the test with the flight examiner and later with yourself) you check in turn every bit of information to decide if you're GO or not for the flight. As a lot of things in aviation, safety is really paramount here.

Once you've practiced cross country flight a bit, you start learning what to do in case of failures during a non-local flights, for example an engine failure in a middle of nowhere, when you have to chose a proper field to land, or a radio failure. And again when you're ready for it (and in case of my local club, once you pass your theoretical exam) you go for cross-country solo flights (of the 10h of solo flight required for taking the test, 5h should be done in cross-country flights). I went again to Troyes (LFQB), then Dijon-Darois (LFGI) and did a three-legs flight to Chalons-Ecury (LFQK) and Pont sur Yonne (LFGO).

And just after that, when I was starting to feel ready for the test, COVID-19 lockdown happened, grounding everyone for a few months. Even after it was over, I felt a bit rusty and had to take some more training. I finally took the test in the beginning of summer, but the first attempt wasn't good enough: I was really stressed, and maybe not completely ready actually. So a bit more training during summer, and finally in September I took the final test part, which was successful this time.

After some paperwork, a new, shiny, Pilot Private License arrived at my door.

And now that I can fly basically when I want, the autumn is finally here with bad weather all day long, so actually planning real flights is a bit tricky. For now I'm still flying solo on familiar trips, but at some point I should be able to bring a passenger with me (on the Aquila) and at some point migrate to a four-seaters like the DR400, ubiquitous in France.

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