Search Results: "sten"

14 March 2024

Freexian Collaborators: Monthly report about Debian Long Term Support, February 2024 (by Roberto C. S nchez)

Like each month, have a look at the work funded by Freexian s Debian LTS offering.

Debian LTS contributors In February, 18 contributors have been paid to work on Debian LTS, their reports are available:
  • Abhijith PA did 10.0h (out of 14.0h assigned), thus carrying over 4.0h to the next month.
  • Adrian Bunk did 13.5h (out of 24.25h assigned and 41.75h from previous period), thus carrying over 52.5h to the next month.
  • Bastien Roucari s did 20.0h (out of 20.0h assigned).
  • Ben Hutchings did 2.0h (out of 14.5h assigned and 9.5h from previous period), thus carrying over 22.0h to the next month.
  • Chris Lamb did 18.0h (out of 18.0h assigned).
  • Daniel Leidert did 10.0h (out of 10.0h assigned).
  • Emilio Pozuelo Monfort did 3.0h (out of 28.25h assigned and 31.75h from previous period), thus carrying over 57.0h to the next month.
  • Guilhem Moulin did 7.25h (out of 4.75h assigned and 15.25h from previous period), thus carrying over 12.75h to the next month.
  • Holger Levsen did 0.5h (out of 3.5h assigned and 8.5h from previous period), thus carrying over 11.5h to the next month.
  • Lee Garrett did 0.0h (out of 18.25h assigned and 41.75h from previous period), thus carrying over 60.0h to the next month.
  • Markus Koschany did 40.0h (out of 40.0h assigned).
  • Roberto C. S nchez did 3.5h (out of 8.75h assigned and 3.25h from previous period), thus carrying over 8.5h to the next month.
  • Santiago Ruano Rinc n did 13.5h (out of 13.5h assigned and 2.5h from previous period), thus carrying over 2.5h to the next month.
  • Sean Whitton did 4.5h (out of 0.5h assigned and 5.5h from previous period), thus carrying over 1.5h to the next month.
  • Sylvain Beucler did 24.5h (out of 27.75h assigned and 32.25h from previous period), thus carrying over 35.5h to the next month.
  • Thorsten Alteholz did 14.0h (out of 14.0h assigned).
  • Tobias Frost did 12.0h (out of 12.0h assigned).
  • Utkarsh Gupta did 11.25h (out of 26.75h assigned and 33.25h from previous period), thus carrying over 48.75 to the next month.

Evolution of the situation In February, we have released 17 DLAs. The number of DLAs published during February was a bit lower than usual, as there was much work going on in the area of triaging CVEs (a number of which turned out to not affect Debia buster, and others which ended up being duplicates, or otherwise determined to be invalid). Of the packages which did receive updates, notable were sudo (to fix a privilege management issue), and iwd and wpa (both of which suffered from authentication bypass vulnerabilities). While this has already been already announced in the Freexian blog, we would like to mention here the start of the Long Term Support project for Samba 4.17. You can find all the important details in that post, but we would like to highlight that it is thanks to our LTS sponsors that we are able to fund the work from our partner, Catalyst, towards improving the security support of Samba in Debian 12 (Bookworm).

Thanks to our sponsors Sponsors that joined recently are in bold.

13 March 2024

Freexian Collaborators: Debian Contributions: Upcoming Improvements to Salsa CI, /usr-move, packaging simplemonitor, and more! (by Utkarsh Gupta)

Contributing to Debian is part of Freexian s mission. This article covers the latest achievements of Freexian and their collaborators. All of this is made possible by organizations subscribing to our Long Term Support contracts and consulting services.

/usr-move, by Helmut Grohne Much of the work was spent on handling interaction with time time64 transition and sending patches for mitigating fallout. The set of packages relevant to debootstrap is mostly converted and the patches for glibc and base-files have been refined due to feedback from the upload to Ubuntu noble. Beyond this, he sent patches for all remaining packages that cannot move their files with dh-sequence-movetousr and packages using dpkg-divert in ways that dumat would not recognize.

Upcoming improvements to Salsa CI, by Santiago Ruano Rinc n Last month, Santiago Ruano Rinc n started the work on integrating sbuild into the Salsa CI pipeline. Initially, Santiago used sbuild with the unshare chroot mode. However, after discussion with josch, jochensp and helmut (thanks to them!), it turns out that the unshare mode is not the most suitable for the pipeline, since the level of isolation it provides is not needed, and some test suites would fail (eg: krb5). Additionally, one of the requirements of the build job is the use of ccache, since it is needed by some C/C++ large projects to reduce the compilation time. In the preliminary work with unshare last month, it was not possible to make ccache to work. Finally, Santiago changed the chroot mode, and now has a couple of POC (cf: 1 and 2) that rely on the schroot and sudo, respectively. And the good news is that ccache is successfully used by sbuild with schroot! The image here comes from an example of building grep. At the end of the build, ccache -s shows the statistics of the cache that it used, and so a little more than half of the calls of that job were cacheable. The most important pieces are in place to finish the integration of sbuild into the pipeline. Other than that, Santiago also reviewed the very useful merge request !346, made by IOhannes zm lnig to autodetect the release from debian/changelog. As agreed with IOhannes, Santiago is preparing a merge request to include the release autodetection use case in the very own Salsa CI s CI.

Packaging simplemonitor, by Carles Pina i Estany Carles started using simplemonitor in 2017, opened a WNPP bug in 2022 and started packaging simplemonitor dependencies in October 2023. After packaging five direct and indirect dependencies, Carles finally uploaded simplemonitor to unstable in February. During the packaging of simplemonitor, Carles reported a few issues to upstream. Some of these were to make the simplemonitor package build and run tests reproducibly. A reproducibility issue was reprotest overriding the timezone, which broke simplemonitor s tests. There have been discussions on resolving this upstream in simplemonitor and in reprotest, too. Carles also started upgrading or improving some of simplemonitor s dependencies.

Miscellaneous contributions
  • Stefano Rivera spent some time doing admin on debian.social infrastructure. Including dealing with a spike of abuse on the Jitsi server.
  • Stefano started to prepare a new release of dh-python, including cleaning out a lot of old Python 2.x related code. Thanks to Niels Thykier (outside Freexian) for spear-heading this work.
  • DebConf 24 planning is beginning. Stefano discussed venues and finances with the local team and remotely supported a site-visit by Nattie (outside Freexian).
  • Also in the DebConf 24 context, Santiago took part in discussions and preparations related to the Content Team.
  • A JIT bug was reported against pypy3 in Debian Bookworm. Stefano bisected the upstream history to find the patch (it was already resolved upstream) and released an update to pypy3 in bookworm.
  • Enrico participated in /usr-merge discussions with Helmut.
  • Colin Watson backported a python-channels-redis fix to bookworm, rediscovered while working on debusine.
  • Colin dug into a cluster of celery build failures and tracked the hardest bit down to a Python 3.12 regression, now fixed in unstable. celery should be back in testing once the 64-bit time_t migration is out of the way.
  • Thorsten Alteholz uploaded a new upstream version of cpdb-libs. Unfortunately upstream changed the naming of their release tags, so updating the watch file was a bit demanding. Anyway this version 2.0 is a huge step towards introduction of the new Common Print Dialog Backends.
  • Helmut send patches for 48 cross build failures.
  • Helmut changed debvm to use mkfs.ext4 instead of genext2fs.
  • Helmut sent a debci MR for improving collector robustness.
  • In preparation for DebConf 25, Santiago worked on the Brest Bid.

10 March 2024

Thorsten Alteholz: My Debian Activities in February 2024

FTP master This month I accepted 242 and rejected 42 packages. The overall number of packages that got accepted was 251.

This was just a short month and the weather outside was not really motivating. I hope it will be better in March. Debian LTS This was my hundred-sixteenth month that I did some work for the Debian LTS initiative, started by Raphael Hertzog at Freexian. During my allocated time I uploaded: I also started to work on qtbase-opensource-src (an update is needed for ELTS, so an LTS update seems to be appropriate as well, especially as there are postponed CVE). Debian ELTS This month was the sixty-seventth ELTS month. During my allocated time I uploaded: The upload of bind9 was a bit exciting, but all occuring issues with the new upload workflow could be quickly fixed by Helmut and the packages finally reached their destination. I wonder why it is always me who stumbles upon special cases? This month I also worked on the Jessie and Stretch updates for exim4. I also started to work on an update for qtbase-opensource-src in Stretch (and LTS and other releases as well). Debian Printing This month I uploaded new upstream versions of: This work is generously funded by Freexian! Debian Matomo I started a new team debian-matomo-maintainers. Within this team all matomo related packages should be handled. PHP PEAR or PECL packages shall be still maintained in their corresponding teams. This month I uploaded: This work is generously funded by Freexian! Debian Astro This month I uploaded a new upstream version of: Debian IoT This month I uploaded new upstream versions of:

9 March 2024

Reproducible Builds: Reproducible Builds in February 2024

Welcome to the February 2024 report from the Reproducible Builds project! In our reports, we try to outline what we have been up to over the past month as well as mentioning some of the important things happening in software supply-chain security.

Reproducible Builds at FOSDEM 2024 Core Reproducible Builds developer Holger Levsen presented at the main track at FOSDEM on Saturday 3rd February this year in Brussels, Belgium. However, that wasn t the only talk related to Reproducible Builds. However, please see our comprehensive FOSDEM 2024 news post for the full details and links.

Maintainer Perspectives on Open Source Software Security Bernhard M. Wiedemann spotted that a recent report entitled Maintainer Perspectives on Open Source Software Security written by Stephen Hendrick and Ashwin Ramaswami of the Linux Foundation sports an infographic which mentions that 56% of [polled] projects support reproducible builds .

Mailing list highlights From our mailing list this month:

Distribution work In Debian this month, 5 reviews of Debian packages were added, 22 were updated and 8 were removed this month adding to Debian s knowledge about identified issues. A number of issue types were updated as well. [ ][ ][ ][ ] In addition, Roland Clobus posted his 23rd update of the status of reproducible ISO images on our mailing list. In particular, Roland helpfully summarised that all major desktops build reproducibly with bullseye, bookworm, trixie and sid provided they are built for a second time within the same DAK run (i.e. [within] 6 hours) and that there will likely be further work at a MiniDebCamp in Hamburg. Furthermore, Roland also responded in-depth to a query about a previous report
Fedora developer Zbigniew J drzejewski-Szmek announced a work-in-progress script called fedora-repro-build that attempts to reproduce an existing package within a koji build environment. Although the projects README file lists a number of fields will always or almost always vary and there is a non-zero list of other known issues, this is an excellent first step towards full Fedora reproducibility.
Jelle van der Waa introduced a new linter rule for Arch Linux packages in order to detect cache files leftover by the Sphinx documentation generator which are unreproducible by nature and should not be packaged. At the time of writing, 7 packages in the Arch repository are affected by this.
Elsewhere, Bernhard M. Wiedemann posted another monthly update for his work elsewhere in openSUSE.

diffoscope diffoscope is our in-depth and content-aware diff utility that can locate and diagnose reproducibility issues. This month, Chris Lamb made a number of changes such as uploading versions 256, 257 and 258 to Debian and made the following additional changes:
  • Use a deterministic name instead of trusting gpg s use-embedded-filenames. Many thanks to Daniel Kahn Gillmor dkg@debian.org for reporting this issue and providing feedback. [ ][ ]
  • Don t error-out with a traceback if we encounter struct.unpack-related errors when parsing Python .pyc files. (#1064973). [ ]
  • Don t try and compare rdb_expected_diff on non-GNU systems as %p formatting can vary, especially with respect to MacOS. [ ]
  • Fix compatibility with pytest 8.0. [ ]
  • Temporarily fix support for Python 3.11.8. [ ]
  • Use the 7zip package (over p7zip-full) after a Debian package transition. (#1063559). [ ]
  • Bump the minimum Black source code reformatter requirement to 24.1.1+. [ ]
  • Expand an older changelog entry with a CVE reference. [ ]
  • Make test_zip black clean. [ ]
In addition, James Addison contributed a patch to parse the headers from the diff(1) correctly [ ][ ] thanks! And lastly, Vagrant Cascadian pushed updates in GNU Guix for diffoscope to version 255, 256, and 258, and updated trydiffoscope to 67.0.6.

reprotest reprotest is our tool for building the same source code twice in different environments and then checking the binaries produced by each build for any differences. This month, Vagrant Cascadian made a number of changes, including:
  • Create a (working) proof of concept for enabling a specific number of CPUs. [ ][ ]
  • Consistently use 398 days for time variation rather than choosing randomly and update README.rst to match. [ ][ ]
  • Support a new --vary=build_path.path option. [ ][ ][ ][ ]

Website updates There were made a number of improvements to our website this month, including:

Reproducibility testing framework The Reproducible Builds project operates a comprehensive testing framework (available at tests.reproducible-builds.org) in order to check packages and other artifacts for reproducibility. In February, a number of changes were made by Holger Levsen:
  • Debian-related changes:
    • Temporarily disable upgrading/bootstrapping Debian unstable and experimental as they are currently broken. [ ][ ]
    • Use the 64-bit amd64 kernel on all i386 nodes; no more 686 PAE kernels. [ ]
    • Add an Erlang package set. [ ]
  • Other changes:
    • Grant Jan-Benedict Glaw shell access to the Jenkins node. [ ]
    • Enable debugging for NetBSD reproducibility testing. [ ]
    • Use /usr/bin/du --apparent-size in the Jenkins shell monitor. [ ]
    • Revert reproducible nodes: mark osuosl2 as down . [ ]
    • Thanks again to Codethink, for they have doubled the RAM on our arm64 nodes. [ ]
    • Only set /proc/$pid/oom_score_adj to -1000 if it has not already been done. [ ]
    • Add the opemwrt-target-tegra and jtx task to the list of zombie jobs. [ ][ ]
Vagrant Cascadian also made the following changes:
  • Overhaul the handling of OpenSSH configuration files after updating from Debian bookworm. [ ][ ][ ]
  • Add two new armhf architecture build nodes, virt32z and virt64z, and insert them into the Munin monitoring. [ ][ ] [ ][ ]
In addition, Alexander Couzens updated the OpenWrt configuration in order to replace the tegra target with mpc85xx [ ], Jan-Benedict Glaw updated the NetBSD build script to use a separate $TMPDIR to mitigate out of space issues on a tmpfs-backed /tmp [ ] and Zheng Junjie added a link to the GNU Guix tests [ ]. Lastly, node maintenance was performed by Holger Levsen [ ][ ][ ][ ][ ][ ] and Vagrant Cascadian [ ][ ][ ][ ].

Upstream patches The Reproducible Builds project detects, dissects and attempts to fix as many currently-unreproducible packages as possible. We endeavour to send all of our patches upstream where appropriate. This month, we wrote a large number of such patches, including:
If you are interested in contributing to the Reproducible Builds project, please visit our Contribute page on our website. However, you can get in touch with us via:

7 March 2024

Valhalla's Things: Jeans, step two. And three. And four.

Posted on March 7, 2024
Tags: madeof:atoms, FreeSoftWear
A woman wearing a regular pair of slim-cut black denim jeans. I was working on what looked like a good pattern for a pair of jeans-shaped trousers, and I knew I wasn t happy with 200-ish g/m cotton-linen for general use outside of deep summer, but I didn t have a source for proper denim either (I had been low-key looking for it for a long time). Then one day I looked at an article I had saved about fabric shops that sell technical fabric and while window-shopping on one I found that they had a decent selection of denim in a decent weight. I decided it was a sign, and decided to buy the two heaviest denim they had: a 100% cotton, 355 g/m one and a 97% cotton, 3% elastane at 385 g/m 1; the latter was a bit of compromise as I shouldn t really be buying fabric adulterated with the Scourge of Humanity, but it was heavier than the plain one, and I may be having a thing for tightly fitting jeans, so this may be one of the very few woven fabric where I m not morally opposed to its existence. And, I d like to add, I resisted buying any of the very nice wools they also seem to carry, other than just a couple of samples. Since the shop only sold in 1 meter increments, and I needed about 1.5 meters for each pair of jeans, I decided to buy 3 meters per type, and have enough to make a total of four pair of jeans. A bit more than I strictly needed, maybe, but I was completely out of wearable day-to-day trousers. a cardboard box with neatly folded black denim, covered in semi-transparent plastic. The shop sent everything very quickly, the courier took their time (oh, well) but eventually delivered my fabric on a sunny enough day that I could wash it and start as soon as possible on the first pair. The pattern I did in linen was a bit too fitting, but I was afraid I had widened it a bit too much, so I did the first pair in the 100% cotton denim. Sewing them took me about a week of early mornings and late afternoons, excluding the weekend, and my worries proved false: they were mostly just fine. The only bit that could have been a bit better is the waistband, which is a tiny bit too wide on the back: it s designed to be so for comfort, but the next time I should pull the elastic a bit more, so that it stays closer to the body. The same from the back, showing the applied pockets with a sewn logo. I wore those jeans daily for the rest of the week, and confirmed that they were indeed comfortable and the pattern was ok, so on the next Monday I started to cut the elastic denim. I decided to cut and sew two pairs, assembly-line style, using the shaped waistband for one of them and the straight one for the other one. I started working on them on a Monday, and on that week I had a couple of days when I just couldn t, plus I completely skipped sewing on the weekend, but on Tuesday the next week one pair was ready and could be worn, and the other one only needed small finishes. A woman wearing another pair of jeans; the waistband here is shaped to fit rather than having elastic. And I have to say, I m really, really happy with the ones with a shaped waistband in elastic denim, as they fit even better than the ones with a straight waistband gathered with elastic. Cutting it requires more fabric, but I think it s definitely worth it. But it will be a problem for a later time: right now three pairs of jeans are a good number to keep in rotation, and I hope I won t have to sew jeans for myself for quite some time. A plastic bag with mid-sized offcuts of denim; there is a 30 cm ruler on top that is just wider than the bag I think that the leftovers of plain denim will be used for a skirt or something else, and as for the leftovers of elastic denim, well, there aren t a lot left, but what else I did with them is the topic for another post. Thanks to the fact that they are all slightly different, I ve started to keep track of the times when I wash each pair, and hopefully I will be able to see whether the elastic denim is significantly less durable than the regular, or the added weight compensates for it somewhat. I m not sure I ll manage to remember about saving the data until they get worn, but if I do it will be interesting to know. Oh, and I say I ve finished working on jeans and everything, but I still haven t sewn the belt loops to the third pair. And I m currently wearing them. It s a sewist tradition, or something. :D
  1. The links are to the shop for Italy; you can copy the Codice prodotto and look for it on one of the shop version for other countries (where they apply the right vat etc., but sadly they don t allow to mix and match those settings and the language).

25 February 2024

Russ Allbery: Review: The Fund

Review: The Fund, by Rob Copeland
Publisher: St. Martin's Press
Copyright: 2023
ISBN: 1-250-27694-2
Format: Kindle
Pages: 310
I first became aware of Ray Dalio when either he or his publisher plastered advertisements for The Principles all over the San Francisco 4th and King Caltrain station. If I recall correctly, there were also constant radio commercials; it was a whole thing in 2017. My brain is very good at tuning out advertisements, so my only thought at the time was "some business guy wrote a self-help book." I think I vaguely assumed he was a CEO of some traditional business, since that's usually who writes heavily marketed books like this. I did not connect him with hedge funds or Bridgewater, which I have a bad habit of confusing with Blackwater. The Principles turns out to be more of a laundered cult manual than a self-help book. And therein lies a story. Rob Copeland is currently with The New York Times, but for many years he was the hedge fund reporter for The Wall Street Journal. He covered, among other things, Bridgewater Associates, the enormous hedge fund founded by Ray Dalio. The Fund is a biography of Ray Dalio and a history of Bridgewater from its founding as a vehicle for Dalio's advising business until 2022 when Dalio, after multiple false starts and title shuffles, finally retired from running the company. (Maybe. Based on the history recounted here, it wouldn't surprise me if he was back at the helm by the time you read this.) It is one of the wildest, creepiest, and most abusive business histories that I have ever read. It's probably worth mentioning, as Copeland does explicitly, that Ray Dalio and Bridgewater hate this book and claim it's a pack of lies. Copeland includes some of their denials (and many non-denials that sound as good as confirmations to me) in footnotes that I found increasingly amusing.
A lawyer for Dalio said he "treated all employees equally, giving people at all levels the same respect and extending them the same perks."
Uh-huh. Anyway, I personally know nothing about Bridgewater other than what I learned here and the occasional mention in Matt Levine's newsletter (which is where I got the recommendation for this book). I have no independent information whether anything Copeland describes here is true, but Copeland provides the typical extensive list of notes and sourcing one expects in a book like this, and Levine's comments indicated it's generally consistent with Bridgewater's industry reputation. I think this book is true, but since the clear implication is that the world's largest hedge fund was primarily a deranged cult whose employees mostly spied on and rated each other rather than doing any real investment work, I also have questions, not all of which Copeland answers to my satisfaction. But more on that later. The center of this book are the Principles. These were an ever-changing list of rules and maxims for how people should conduct themselves within Bridgewater. Per Copeland, although Dalio later published a book by that name, the version of the Principles that made it into the book was sanitized and significantly edited down from the version used inside the company. Dalio was constantly adding new ones and sometimes changing them, but the common theme was radical, confrontational "honesty": never being silent about problems, confronting people directly about anything that they did wrong, and telling people all of their faults so that they could "know themselves better." If this sounds like textbook abusive behavior, you have the right idea. This part Dalio admits to openly, describing Bridgewater as a firm that isn't for everyone but that achieves great results because of this culture. But the uncomfortably confrontational vibes are only the tip of the iceberg of dysfunction. Here are just a few of the ways this played out according to Copeland: In one of the common and all-too-disturbing connections between Wall Street finance and the United States' dysfunctional government, James Comey (yes, that James Comey) ran internal security for Bridgewater for three years, meaning that he was the one who pulled evidence from surveillance cameras for Dalio to use to confront employees during his trials. In case the cult vibes weren't strong enough already, Bridgewater developed its own idiosyncratic language worthy of Scientology. The trials were called "probings," firing someone was called "sorting" them, and rating them was called "dotting," among many other Bridgewater-specific terms. Needless to say, no one ever probed Dalio himself. You will also be completely unsurprised to learn that Copeland documents instances of sexual harassment and discrimination at Bridgewater, including some by Dalio himself, although that seems to be a relatively small part of the overall dysfunction. Dalio was happy to publicly humiliate anyone regardless of gender. If you're like me, at this point you're probably wondering how Bridgewater continued operating for so long in this environment. (Per Copeland, since Dalio's retirement in 2022, Bridgewater has drastically reduced the cult-like behaviors, deleted its archive of probings, and de-emphasized the Principles.) It was not actually a religious cult; it was a hedge fund that has to provide investment services to huge, sophisticated clients, and by all accounts it's a very successful one. Why did this bizarre nightmare of a workplace not interfere with Bridgewater's business? This, I think, is the weakest part of this book. Copeland makes a few gestures at answering this question, but none of them are very satisfying. First, it's clear from Copeland's account that almost none of the employees of Bridgewater had any control over Bridgewater's investments. Nearly everyone was working on other parts of the business (sales, investor relations) or on cult-related obsessions. Investment decisions (largely incorporated into algorithms) were made by a tiny core of people and often by Dalio himself. Bridgewater also appears to not trade frequently, unlike some other hedge funds, meaning that they probably stay clear of the more labor-intensive high-frequency parts of the business. Second, Bridgewater took off as a hedge fund just before the hedge fund boom in the 1990s. It transformed from Dalio's personal consulting business and investment newsletter to a hedge fund in 1990 (with an earlier investment from the World Bank in 1987), and the 1990s were a very good decade for hedge funds. Bridgewater, in part due to Dalio's connections and effective marketing via his newsletter, became one of the largest hedge funds in the world, which gave it a sort of institutional momentum. No one was questioned for putting money into Bridgewater even in years when it did poorly compared to its rivals. Third, Dalio used the tried and true method of getting free publicity from the financial press: constantly predict an upcoming downturn, and aggressively take credit whenever you were right. From nearly the start of his career, Dalio predicted economic downturns year after year. Bridgewater did very well in the 2000 to 2003 downturn, and again during the 2008 financial crisis. Dalio aggressively takes credit for predicting both of those downturns and positioning Bridgewater correctly going into them. This is correct; what he avoids mentioning is that he also predicted downturns in every other year, the majority of which never happened. These points together create a bit of an answer, but they don't feel like the whole picture and Copeland doesn't connect the pieces. It seems possible that Dalio may simply be good at investing; he reads obsessively and clearly enjoys thinking about markets, and being an abusive cult leader doesn't take up all of his time. It's also true that to some extent hedge funds are semi-free money machines, in that once you have a sufficient quantity of money and political connections you gain access to investment opportunities and mechanisms that are very likely to make money and that the typical investor simply cannot access. Dalio is clearly good at making personal connections, and invested a lot of effort into forming close ties with tricky clients such as pools of Chinese money. Perhaps the most compelling explanation isn't mentioned directly in this book but instead comes from Matt Levine. Bridgewater touts its algorithmic trading over humans making individual trades, and there is some reason to believe that consistently applying an algorithm without regard to human emotion is a solid trading strategy in at least some investment areas. Levine has asked in his newsletter, tongue firmly in cheek, whether the bizarre cult-like behavior and constant infighting is a strategy to distract all the humans and keep them from messing with the algorithm and thus making bad decisions. Copeland leaves this question unsettled. Instead, one comes away from this book with a clear vision of the most dysfunctional workplace I have ever heard of, and an endless litany of bizarre events each more astonishing than the last. If you like watching train wrecks, this is the book for you. The only drawback is that, unlike other entries in this genre such as Bad Blood or Billion Dollar Loser, Bridgewater is a wildly successful company, so you don't get the schadenfreude of seeing a house of cards collapse. You do, however, get a helpful mental model to apply to the next person who tries to talk to you about "radical honesty" and "idea meritocracy." The flaw in this book is that the existence of an organization like Bridgewater is pointing to systematic flaws in how our society works, which Copeland is largely uninterested in interrogating. "How could this have happened?" is a rather large question to leave unanswered. The sheer outrageousness of Dalio's behavior also gets a bit tiring by the end of the book, when you've seen the patterns and are hearing about the fourth variation. But this is still an astonishing book, and a worthy entry in the genre of capitalism disasters. Rating: 7 out of 10

24 February 2024

Niels Thykier: Language Server for Debian: Spellchecking

This is my third update on writing a language server for Debian packaging files, which aims at providing a better developer experience for Debian packagers. Lets go over what have done since the last report.
Semantic token support I have added support for what the Language Server Protocol (LSP) call semantic tokens. These are used to provide the editor insights into tokens of interest for users. Allegedly, this is what editors would use for syntax highlighting as well. Unfortunately, eglot (emacs) does not support semantic tokens, so I was not able to test this. There is a 3-year old PR for supporting with the last update being ~3 month basically saying "Please sign the Copyright Assignment". I pinged the GitHub issue in the hopes it will get unstuck. For good measure, I also checked if I could try it via neovim. Before installing, I read the neovim docs, which helpfully listed the features supported. Sadly, I did not spot semantic tokens among those and parked from there. That was a bit of a bummer, but I left the feature in for now. If you have an LSP capable editor that supports semantic tokens, let me know how it works for you! :)
Spellchecking Finally, I implemented something Otto was missing! :) This stared with Paul Wise reminding me that there were Python binding for the hunspell spellchecker. This enabled me to get started with a quick prototype that spellchecked the Description fields in debian/control. I also added spellchecking of comments while I was add it. The spellchecker runs with the standard en_US dictionary from hunspell-en-us, which does not have a lot of technical terms in it. Much less any of the Debian specific slang. I spend considerable time providing a "built-in" wordlist for technical and Debian specific slang to overcome this. I also made a "wordlist" for known Debian people that the spellchecker did not recognise. Said wordlist is fairly short as a proof of concept, and I fully expect it to be community maintained if the language server becomes a success. My second problem was performance. As I had suspected that spellchecking was not the fastest thing in the world. Therefore, I added a very small language server for the debian/changelog, which only supports spellchecking the textual part. Even for a small changelog of a 1000 lines, the spellchecking takes about 5 seconds, which confirmed my suspicion. With every change you do, the existing diagnostics hangs around for 5 seconds before being updated. Notably, in emacs, it seems that diagnostics gets translated into an absolute character offset, so all diagnostics after the change gets misplaced for every character you type. Now, there is little I could do to speed up hunspell. But I can, as always, cheat. The way diagnostics work in the LSP is that the server listens to a set of notifications like "document opened" or "document changed". In a response to that, the LSP can start its diagnostics scanning of the document and eventually publish all the diagnostics to the editor. The spec is quite clear that the server owns the diagnostics and the diagnostics are sent as a "notification" (that is, fire-and-forgot). Accordingly, there is nothing that prevents the server from publishing diagnostics multiple times for a single trigger. The only requirement is that the server publishes the accumulated diagnostics in every publish (that is, no delta updating). Leveraging this, I had the language server for debian/changelog scan the document and publish once for approximately every 25 typos (diagnostics) spotted. This means you quickly get your first result and that clears the obsolete diagnostics. Thereafter, you get frequent updates to the remainder of the document if you do not perform any further changes. That is, up to a predefined max of typos, so we do not overload the client for longer changelogs. If you do any changes, it resets and starts over. The only bit missing was dealing with concurrency. By default, a pygls language server is single threaded. It is not great if the language server hangs for 5 seconds everytime you type anything. Fortunately, pygls has builtin support for asyncio and threaded handlers. For now, I did an async handler that await after each line and setup some manual detection to stop an obsolete diagnostics run. This means the server will fairly quickly abandon an obsolete run. Also, as a side-effect of working on the spellchecking, I fixed multiple typos in the changelog of debputy. :)
Follow up on the "What next?" from my previous update In my previous update, I mentioned I had to finish up my python-debian changes to support getting the location of a token in a deb822 file. That was done, the MR is now filed, and is pending review. Hopefully, it will be merged and uploaded soon. :) I also submitted my proposal for a different way of handling relationship substvars to debian-devel. So far, it seems to have received only positive feedback. I hope it stays that way and we will have this feature soon. Guillem proposed to move some of this into dpkg, which might delay my plans a bit. However, it might be for the better in the long run, so I will wait a bit to see what happens on that front. :) As noted above, I managed to add debian/changelog as a support format for the language server. Even if it only does spellchecking and trimming of trailing newlines on save, it technically is a new format and therefore cross that item off my list. :D Unfortunately, I did not manage to write a linter variant that does not involve using an LSP-capable editor. So that is still pending. Instead, I submitted an MR against elpa-dpkg-dev-el to have it recognize all the fields that the debian/control LSP knows about at this time to offset the lack of semantic token support in eglot.
From here... My sprinting on this topic will soon come to an end, so I have to a bit more careful now with what tasks I open! I think I will narrow my focus to providing a batch linting interface. Ideally, with an auto-fix for some of the more mechanical issues, where this is little doubt about the answer. Additionally, I think the spellchecking will need a bit more maturing. My current code still trips on naming patterns that are "clearly" verbatim or code references like things written in CamelCase or SCREAMING_SNAKE_CASE. That gets annoying really quickly. It also trips on a lot of commands like dpkg-gencontrol, but that is harder to fix since it could have been a real word. I think those will have to be fixed people using quotes around the commands. Maybe the most popular ones will end up in the wordlist. Beyond that, I will play it by ear if I have any time left. :)

21 February 2024

Niels Thykier: Expanding on the Language Server (LSP) support for debian/control

I have spent some more time on improving my language server for debian/control. Today, I managed to provide the following features:

  • The X- style prefixes for field names are now understood and handled. This means the language server now considers XC-Package-Type the same as Package-Type.

  • More diagnostics:

    • Fields without values now trigger an error marker
    • Duplicated fields now trigger an error marker
    • Fields used in the wrong paragraph now trigger an error marker
    • Typos in field names or values now trigger a warning marker. For field names, X- style prefixes are stripped before typo detection is done.
    • The value of the Section field is now validated against a dataset of known sections and trigger a warning marker if not known.

  • The "on-save trim end of line whitespace" now works. I had a logic bug in the server side code that made it submit "no change" edits to the editor.

  • The language server now provides "hover" documentation for field names. There is a small screenshot of this below. Sadly, emacs does not support markdown or, if it does, it does not announce the support for markdown. For now, all the documentation is always in markdown format and the language server will tag it as either markdown or plaintext depending on the announced support.

  • The language server now provides quick fixes for some of the more trivial problems such as deprecated fields or typos of fields and values.

  • Added more known fields including the XS-Autobuild field for non-free packages along with a link to the relevant devref section in its hover doc.

This covers basically all my known omissions from last update except spellchecking of the Description field. An image of emacs showing documentation for the Provides field from the language server.
Spellchecking Personally, I feel spellchecking would be a very welcome addition to the current feature set. However, reviewing my options, it seems that most of the spellchecking python libraries out there are not packaged for Debian, or at least not other the name I assumed they would be. The alternative is to pipe the spellchecking to another program like aspell list. I did not test this fully, but aspell list does seem to do some input buffering that I cannot easily default (at least not in the shell). Though, either way, the logic for this will not be trivial and aspell list does not seem to include the corrections either. So best case, you would get typo markers but no suggestions for what you should have typed. Not ideal. Additionally, I am also concerned with the performance for this feature. For d/control, it will be a trivial matter in practice. However, I would be reusing this for d/changelog which is 99% free text with plenty of room for typos. For a regular linter, some slowness is acceptable as it is basically a batch tool. However, for a language server, this potentially translates into latency for your edits and that gets annoying. While it is definitely on my long term todo list, I am a bit afraid that it can easily become a time sink. Admittedly, this does annoy me, because I wanted to cross off at least one of Otto's requested features soon.
On wrap-and-sort support The other obvious request from Otto would be to automate wrap-and-sort formatting. Here, the problem is that "we" in Debian do not agree on the one true formatting of debian/control. In fact, I am fairly certain we do not even agree on whether we should all use wrap-and-sort. This implies we need a style configuration. However, if we have a style configuration per person, then you get style "ping-pong" for packages where the co-maintainers do not all have the same style configuration. Additionally, it is very likely that you are a member of multiple packaging teams or groups that all have their own unique style. Ergo, only having a personal config file is doomed to fail. The only "sane" option here that I can think of is to have or support "per package" style configuration. Something that would be committed to git, so the tooling would automatically pick up the configuration. Obviously, that is not fun for large packaging teams where you have to maintain one file per package if you want a consistent style across all packages. But it beats "style ping-pong" any day of the week. Note that I am perfectly open to having a personal configuration file as a fallback for when the "per package" configuration file is absent. The second problem is the question of which format to use and what to name this file. Since file formats and naming has never been controversial at all, this will obviously be the easy part of this problem. But the file should be parsable by both wrap-and-sort and the language server, so you get the same result regardless of which tool you use. If we do not ensure this, then we still have the style ping-pong problem as people use different tools. This also seems like time sink with no end. So, what next then...?
What next? On the language server front, I will have a look at its support for providing semantic hints to the editors that might be used for syntax highlighting. While I think most common Debian editors have built syntax highlighting already, I would like this language server to stand on its own. I would like us to be in a situation where we do not have implement yet another editor extension for Debian packaging files. At least not for editors that support the LSP spec. On a different front, I have an idea for how we go about relationship related substvars. It is not directly related to this language server, except I got triggered by the language server "missing" a diagnostic for reminding people to add the magic Depends: $ misc:Depends [, $ shlibs:Depends ] boilerplate. The magic boilerplate that you have to write even though we really should just fix this at a tooling level instead. Energy permitting, I will formulate a proposal for that and send it to debian-devel. Beyond that, I think I might start adding support for another file. I also need to wrap up my python-debian branch, so I can get the position support into the Debian soon, which would remove one papercut for using this language server. Finally, it might be interesting to see if I can extract a "batch-linter" version of the diagnostics and related quickfix features. If nothing else, the "linter" variant would enable many of you to get a "mini-Lintian" without having to do a package build first.

19 February 2024

Matthew Garrett: Debugging an odd inability to stream video

We have a cabin out in the forest, and when I say "out in the forest" I mean "in a national forest subject to regulation by the US Forest Service" which means there's an extremely thick book describing the things we're allowed to do and (somewhat longer) not allowed to do. It's also down in the bottom of a valley surrounded by tall trees (the whole "forest" bit). There used to be AT&T copper but all that infrastructure burned down in a big fire back in 2021 and AT&T no longer supply new copper links, and Starlink isn't viable because of the whole "bottom of a valley surrounded by tall trees" thing along with regulations that prohibit us from putting up a big pole with a dish on top. Thankfully there's LTE towers nearby, so I'm simply using cellular data. Unfortunately my provider rate limits connections to video streaming services in order to push them down to roughly SD resolution. The easy workaround is just to VPN back to somewhere else, which in my case is just a Wireguard link back to San Francisco.

This worked perfectly for most things, but some streaming services simply wouldn't work at all. Attempting to load the video would just spin forever. Running tcpdump at the local end of the VPN endpoint showed a connection being established, some packets being exchanged, and then nothing. The remote service appeared to just stop sending packets. Tcpdumping the remote end of the VPN showed the same thing. It wasn't until I looked at the traffic on the VPN endpoint's external interface that things began to become clear.

This probably needs some background. Most network infrastructure has a maximum allowable packet size, which is referred to as the Maximum Transmission Unit or MTU. For ethernet this defaults to 1500 bytes, and these days most links are able to handle packets of at least this size, so it's pretty typical to just assume that you'll be able to send a 1500 byte packet. But what's important to remember is that that doesn't mean you have 1500 bytes of packet payload - that 1500 bytes includes whatever protocol level headers are on there. For TCP/IP you're typically looking at spending around 40 bytes on the headers, leaving somewhere around 1460 bytes of usable payload. And if you're using a VPN, things get annoying. In this case the original packet becomes the payload of a new packet, which means it needs another set of TCP (or UDP) and IP headers, and probably also some VPN header. This still all needs to fit inside the MTU of the link the VPN packet is being sent over, so if the MTU of that is 1500, the effective MTU of the VPN interface has to be lower. For Wireguard, this works out to an effective MTU of 1420 bytes. That means simply sending a 1500 byte packet over a Wireguard (or any other VPN) link won't work - adding the additional headers gives you a total packet size of over 1500 bytes, and that won't fit into the underlying link's MTU of 1500.

And yet, things work. But how? Faced with a packet that's too big to fit into a link, there are two choices - break the packet up into multiple smaller packets ("fragmentation") or tell whoever's sending the packet to send smaller packets. Fragmentation seems like the obvious answer, so I'd encourage you to read Valerie Aurora's article on how fragmentation is more complicated than you think. tl;dr - if you can avoid fragmentation then you're going to have a better life. You can explicitly indicate that you don't want your packets to be fragmented by setting the Don't Fragment bit in your IP header, and then when your packet hits a link where your packet exceeds the link MTU it'll send back a packet telling the remote that it's too big, what the actual MTU is, and the remote will resend a smaller packet. This avoids all the hassle of handling fragments in exchange for the cost of a retransmit the first time the MTU is exceeded. It also typically works these days, which wasn't always the case - people had a nasty habit of dropping the ICMP packets telling the remote that the packet was too big, which broke everything.

What I saw when I tcpdumped on the remote VPN endpoint's external interface was that the connection was getting established, and then a 1500 byte packet would arrive (this is kind of the behaviour you'd expect for video - the connection handshaking involves a bunch of relatively small packets, and then once you start sending the video stream itself you start sending packets that are as large as possible in order to minimise overhead). This 1500 byte packet wouldn't fit down the Wireguard link, so the endpoint sent back an ICMP packet to the remote telling it to send smaller packets. The remote should then have sent a new, smaller packet - instead, about a second after sending the first 1500 byte packet, it sent that same 1500 byte packet. This is consistent with it ignoring the ICMP notification and just behaving as if the packet had been dropped.

All the services that were failing were failing in identical ways, and all were using Fastly as their CDN. I complained about this on social media and then somehow ended up in contact with the engineering team responsible for this sort of thing - I sent them a packet dump of the failure, they were able to reproduce it, and it got fixed. Hurray!

(Between me identifying the problem and it getting fixed I was able to work around it. The TCP header includes a Maximum Segment Size (MSS) field, which indicates the maximum size of the payload for this connection. iptables allows you to rewrite this, so on the VPN endpoint I simply rewrote the MSS to be small enough that the packets would fit inside the Wireguard MTU. This isn't a complete fix since it's done at the TCP level rather than the IP level - so any large UDP packets would still end up breaking)

I've no idea what the underlying issue was, and at the client end the failure was entirely opaque: the remote simply stopped sending me packets. The only reason I was able to debug this at all was because I controlled the other end of the VPN as well, and even then I wouldn't have been able to do anything about it other than being in the fortuitous situation of someone able to do something about it seeing my post. How many people go through their lives dealing with things just being broken and having no idea why, and how do we fix that?

(Edit: thanks to this comment, it sounds like the underlying issue was a kernel bug that Fastly developed a fix for - under certain configurations, the kernel fails to associate the MTU update with the egress interface and so it continues sending overly large packets)

comment count unavailable comments

12 February 2024

Andrew Cater: Lessons from (and for) colleagues - and, implicitly, how NOT to get on

I have had excellent colleagues both at my day job and, especially, in Debian over the last thirty-odd years. Several have attempted to give me good advice - others have been exemplars. People retire: sadly, people die. What impression do you want to leave behind when you leave here?Belatedly, I've come to realise that obduracy, sheer bloody mindedness, force of will and obstinacy will only get you so far. The following began very much as a tongue in cheek private memo to myself a good few years ago. I showed it to a colleague who suggested at the time that I should share it to a wider audience.

SOME ADVICE YOU MAY BENEFIT FROM

Personal conduct
  • Never argue with someone you believe to be arguing idiotically - a dispassionate bystander may have difficulty telling who's who.
  • You can't make yourself seem reasonable by behaving unreasonably
  • It does not matter how correct your point of view is if you get people's backs up
  • They may all be #####, @@@@@, %%%% and ******* - saying so out loud doesn't help improve matters and may make you seem intemperate.

Working with others
  • Be the change you want to be and behave the way you want others to behave in order to achieve the desired outcome.
  • You can demolish someone's argument constructively and add weight to good points rather than tearing down their ideas and hard work and being ultra-critical and negative - no-one likes to be told "You know - you've got a REALLY ugly baby there"
  • It's easier to work with someone than to work against them and have to apologise repeatedly.
  • Even when you're outstanding and superlative, even you had to learn it all once. Be generous to help others learn: you shouldn't have to teach too many times if you teach correctly once and take time in doing so.

Getting the message across
  • Stop: think: write: review: (peer review if necessary): publish.
  • Clarity is all: just because you understand it doesn't mean anyone else will.
  • It does not matter how correct your point of view is if you put it across badly.
  • If you're giving advice: make sure it is:
  • Considered
  • Constructive
  • Correct as far as you can (and)
  • Refers to other people who may be able to help
  • Say thank you promptly if someone helps you and be prepared to give full credit where credit's due.

Work is like that
  • You may not know all the answers or even have the whole picture - consult, take advice - LISTEN TO THE ADVICE
  • Sometimes the right answer is not the immediately correct answer
  • Corollary: Sometimes the right answer for the business is not your suggested/preferred outcome
  • Corollary: Just because you can do it like that in the real world doesn't mean that you can do it that way inside the business. [This realisation is INTENSELY frustrating but you have to learn to deal with it]
  • DON'T ALWAYS DO IT YOURSELF - Attempt to fix the system, sometimes allow the corporate monster to fail - then do it yourself and fix it. It is always easier and tempting to work round the system and Just Flaming Do It but it doesn't solve problems in the longer term and may create more problems and ill-feeling than it solves.

    [Worked out for Andy Cater for himself after many years of fighting the system as a misguided missile - though he will freely admit that he doesn't always follow them as often as he should :) ]


Freexian Collaborators: Monthly report about Debian Long Term Support, January 2024 (by Roberto C. S nchez)

Like each month, have a look at the work funded by Freexian s Debian LTS offering.

Debian LTS contributors In January, 16 contributors have been paid to work on Debian LTS, their reports are available:
  • Abhijith PA did 14.0h (out of 7.0h assigned and 7.0h from previous period).
  • Bastien Roucari s did 22.0h (out of 16.0h assigned and 6.0h from previous period).
  • Ben Hutchings did 14.5h (out of 8.0h assigned and 16.0h from previous period), thus carrying over 9.5h to the next month.
  • Chris Lamb did 18.0h (out of 18.0h assigned).
  • Daniel Leidert did 10.0h (out of 10.0h assigned).
  • Emilio Pozuelo Monfort did 10.0h (out of 14.75h assigned and 27.0h from previous period), thus carrying over 31.75h to the next month.
  • Guilhem Moulin did 9.75h (out of 25.0h assigned), thus carrying over 15.25h to the next month.
  • Holger Levsen did 3.5h (out of 12.0h assigned), thus carrying over 8.5h to the next month.
  • Markus Koschany did 40.0h (out of 40.0h assigned).
  • Roberto C. S nchez did 8.75h (out of 9.5h assigned and 2.5h from previous period), thus carrying over 3.25h to the next month.
  • Santiago Ruano Rinc n did 13.5h (out of 8.25h assigned and 7.75h from previous period), thus carrying over 2.5h to the next month.
  • Sean Whitton did 0.5h (out of 0.25h assigned and 5.75h from previous period), thus carrying over 5.5h to the next month.
  • Sylvain Beucler did 9.5h (out of 23.25h assigned and 18.5h from previous period), thus carrying over 32.25h to the next month.
  • Thorsten Alteholz did 14.0h (out of 14.0h assigned).
  • Tobias Frost did 12.0h (out of 10.25h assigned and 1.75h from previous period).
  • Utkarsh Gupta did 8.5h (out of 35.75h assigned), thus carrying over 24.75h to the next month.

Evolution of the situation In January, we have released 25 DLAs. A variety of particularly notable packages were updated during January. Among those updates were the Linux kernel (both versions 5.10 and 4.19), mariadb-10.3, openjdk-11, firefox-esr, and thunderbird. In addition to the many other LTS package updates which were released in January, LTS contributors continue their efforts to make impactful contributions both within the Debian community.

Thanks to our sponsors Sponsors that joined recently are in bold.

11 February 2024

Freexian Collaborators: Debian Contributions: Upcoming Improvements to Salsa CI, /usr-move, and more! (by Utkarsh Gupta)

Contributing to Debian is part of Freexian s mission. This article covers the latest achievements of Freexian and their collaborators. All of this is made possible by organizations subscribing to our Long Term Support contracts and consulting services.

Upcoming Improvements to Salsa CI, by Santiago Ruano Rinc n Santiago started picking up the work made by Outreachy Intern, Enock Kashada (a big thanks to him!), to solve some long-standing issues in Salsa CI. Currently, the first job in a Salsa CI pipeline is the extract-source job, used to produce a debianize source tree of the project. This job was introduced to make it possible to build the projects on different architectures, on the subsequent build jobs. However, that extract-source approach is sub-optimal: not only it increases the execution time of the pipeline by some minutes, but also projects whose source tree is too large are not able to use the pipeline. The debianize source tree is passed as an artifact to the build jobs, and for those large projects, the size of their source tree exceeds the Salsa s limits. This is specific issue is documented as issue #195, and the proposed solution is to get rid of the extract-source job, relying on sbuild in the very build job (see issue #296). Switching to sbuild would also help to improve the build source job, solving issues such as #187 and #298. The current work-in-progress is very preliminary, but it has already been possible to run the build (amd64), build-i386 and build-source job using sbuild with the unshare mode. The image on the right shows a pipeline that builds grep. All the test jobs use the artifacts of the new build job. There is a lot of remaining work, mainly making the integration with ccache work. This change could break some things, it will also be important to test how the new pipeline works with complex projects. Also, thanks to Emmanuel Arias, we are proposing a Google Summer of Code 2024 project to improve Salsa CI. As part of the ongoing work in preparation for the GSoC 2024 project, Santiago has proposed a merge request to make more efficient how contributors can test their changes on the Salsa CI pipeline.

/usr-move, by Helmut Grohne In January, we sent most of the moving patches for the set of packages involved with debootstrap. Notably missing is glibc, which turns out harder than anticipated via dumat, because it has Conflicts between different architectures, which dumat does not analyze. Patches for diversion mitigations have been updated in a way to not exhibit any loss anymore. The main change here is that packages which are being diverted now support the diverting packages in transitioning their diversions. We also supported a few packages with non-trivial changes such as netplan.io. dumat has been enhanced to better support derivatives such as Ubuntu.

Miscellaneous contributions
  • Python 3.12 migration trundles on. Stefano Rivera helped port several new packages to support 3.12.
  • Stefano updated the Sphinx configuration of DebConf Video Team s documentation, which was broken by Sphinx 7.
  • Stefano published the videos from the Cambridge MiniDebConf to YouTube and PeerTube.
  • DebConf 24 planning has begun, and Stefano & Utkarsh have started work on this.
  • Utkarsh re-sponsored the upload of golang-github-prometheus-community-pgbouncer-exporter for Lena.
  • Colin Watson added Incus support to autopkgtest.
  • Colin discovered Perl::Critic and used it to tidy up some poor practices in several of his packages, including debconf.
  • Colin did some overdue debconf maintenance, mainly around tidying up error message handling in several places (1, 2, 3).
  • Colin figured out how to update the mirror size documentation in debmirror, last updated in 2010. It should now be much easier to keep it up to date regularly.
  • Colin issued a man-db buster update to clean up some irritations due to strict sandboxing.
  • Thorsten Alteholz adopted two more packages, magicfilter and ifhp, for the debian-printing team. Those packages are the last ones of the latest round of adoptions to preserve the old printing protocol within Debian. If you know of other packages that should be retained, please don t hesitate to contact Thorsten.
  • Enrico participated in /usr-merge discussions with Helmut.
  • Helmut sent patches for 16 cross build failures.
  • Helmut supported Matthias Klose (not affiliated with Freexian) with adding -for-host support to gcc-defaults.
  • Helmut uploaded dput-ng enabling dcut migrate and merging two MRs of Ben Hutchings.
  • Santiago took part in the discussions relating to the EU Cyber Resilience Act (CRA) and the Debian public statement that was published last year. He participated in a meeting with Members of the European Parliament (MEPs), Marcel Kolaja and Karen Melchior, and their teams to clarify some points about the impact of the CRA and Debian and downstream projects, and the improvements in the last version of the proposed regulation.

9 February 2024

Thorsten Alteholz: My Debian Activities in January 2024

FTP master This month I accepted 333 and rejected 31 packages. The overall number of packages that got accepted was 342.

Hooray, I already accepted package number 30000.

The statistic, where I get my numbers from, started in February 2002. Up to now 81694 packages got accepted. Given that I accepted package 20000 in October 2020, would I be able to accept half of the packages that made it through NEW? Debian LTS This was my hundred-fifteenth month that I did some work for the Debian LTS initiative, started by Raphael Hertzog at Freexian. During my allocated time I uploaded: This month I was finally able to really run the test suite of bind9. I already wanted to give up with this package, but Santiago encouraged me to proceed. So, here you are fixed-Buster-version. Jessie and Stretch have to wait a bit until the dust has settled. Last but not least I also did a few days of frontdesk duties. Debian ELTS This month was the sixty-sixth ELTS month. During my allocated time I uploaded: This month I also worked on the Jessie and Stretch updates for bind9. The uploads should happen soon. I also started to work on an update for exim4. Last but not least I did a few days of frontdesk duties. Debian Printing This month I adopted: At the moment these packages are the last adoptions to preserve the old printing protocol within Debian. If you know of other packages that should be retained, please don t hesitate to ask me. But don t wait for too long, I have fun to process RM-bugs :-). This work is generously funded by Freexian! Debian Astro This month I uploaded a new upstream version of: Debian IoT This month I uploaded new upstream versions of: Other stuff This month I uploaded new upstream version of packages, did a source upload for the transition or uploaded it to fix one or the other issue:

7 February 2024

Jonathan Dowland: carbon

I got a new work laptop this year: A Thinkpad X1 Carbon (Gen 11). It wasn't the one I wanted: I'd ordered an X1 Nano, which had a footprint very reminiscent to me of my beloved x40. Never mind! The Carbon is lovely. Despite ostensibly the same size as the T470s it's replacing, it's significantly more portable, and more capable. The two USB-A ports, as well as the full-size HDMI port, are welcome and useful (over the Nano). I used to keep notes on setting up Linux on different types of hardware, but I haven't really bothered now for years. Things Just Work. That's good! My old machine naming schemes are stretched beyond breaking point (and I've re-used my favourite hostname, qusp, one too many times) so I went for something new this time: Riffing on Carbon, I settled (for now) on carbyne, a carbon allotrope which is of interest to nanotechnologists (Seems appropriate)

30 January 2024

Antoine Beaupr : router archeology: the Soekris net5001

Roadkiller was a Soekris net5501 router I used as my main gateway between 2010 and 2016 (for r seau and t l phone). It was upgraded to FreeBSD 8.4-p12 (2014-06-06) and pkgng. It was retired in favor of octavia around 2016. Roughly 10 years later (2024-01-24), I found it in a drawer and, to my surprised, it booted. After wrangling with a RS-232 USB adapter, a null modem cable, and bit rates, I even logged in: 
comBIOS ver. 1.33  20070103  Copyright (C) 2000-2007 Soekris Engineering.
net5501
0512 Mbyte Memory                        CPU Geode LX 500 Mhz 
Pri Mas  WDC WD800VE-00HDT0              LBA Xlt 1024-255-63  78 Gbyte
Slot   Vend Dev  ClassRev Cmd  Stat CL LT HT  Base1    Base2   Int 
-------------------------------------------------------------------
0:01:2 1022 2082 10100000 0006 0220 08 00 00 A0000000 00000000 10
0:06:0 1106 3053 02000096 0117 0210 08 40 00 0000E101 A0004000 11
0:07:0 1106 3053 02000096 0117 0210 08 40 00 0000E201 A0004100 05
0:08:0 1106 3053 02000096 0117 0210 08 40 00 0000E301 A0004200 09
0:09:0 1106 3053 02000096 0117 0210 08 40 00 0000E401 A0004300 12
0:20:0 1022 2090 06010003 0009 02A0 08 40 80 00006001 00006101 
0:20:2 1022 209A 01018001 0005 02A0 08 00 00 00000000 00000000 
0:21:0 1022 2094 0C031002 0006 0230 08 00 80 A0005000 00000000 15
0:21:1 1022 2095 0C032002 0006 0230 08 00 00 A0006000 00000000 15
 4 Seconds to automatic boot.   Press Ctrl-P for entering Monitor.
 
                                            
                                                  ______
                                                    ____  __ ___  ___ 
            Welcome to FreeBSD!                     __   '__/ _ \/ _ \
                                                    __       __/  __/
                                                                      
    1. Boot FreeBSD [default]                     _     _   \___ \___ 
    2. Boot FreeBSD with ACPI enabled             ____   _____ _____
    3. Boot FreeBSD in Safe Mode                    _ \ / ____   __ \
    4. Boot FreeBSD in single user mode             _)   (___         
    5. Boot FreeBSD with verbose logging            _ < \___ \        
    6. Escape to loader prompt                      _)  ____)    __   
    7. Reboot                                                         
                                                  ____/ _____/ _____/
                                            
                                            
                                            
    Select option, [Enter] for default      
    or [Space] to pause timer  5            
  
Copyright (c) 1992-2013 The FreeBSD Project.
Copyright (c) 1979, 1980, 1983, 1986, 1988, 1989, 1991, 1992, 1993, 1994
        The Regents of the University of California. All rights reserved.
FreeBSD is a registered trademark of The FreeBSD Foundation.
FreeBSD 8.4-RELEASE-p12 #5: Fri Jun  6 02:43:23 EDT 2014
    root@roadkiller.anarc.at:/usr/obj/usr/src/sys/ROADKILL i386
gcc version 4.2.2 20070831 prerelease [FreeBSD]
Timecounter "i8254" frequency 1193182 Hz quality 0
CPU: Geode(TM) Integrated Processor by AMD PCS (499.90-MHz 586-class CPU)
  Origin = "AuthenticAMD"  Id = 0x5a2  Family = 5  Model = a  Stepping = 2
  Features=0x88a93d<FPU,DE,PSE,TSC,MSR,CX8,SEP,PGE,CMOV,CLFLUSH,MMX>
  AMD Features=0xc0400000<MMX+,3DNow!+,3DNow!>
real memory  = 536870912 (512 MB)
avail memory = 506445824 (482 MB)
kbd1 at kbdmux0
K6-family MTRR support enabled (2 registers)
ACPI Error: A valid RSDP was not found (20101013/tbxfroot-309)
ACPI: Table initialisation failed: AE_NOT_FOUND
ACPI: Try disabling either ACPI or apic support.
cryptosoft0: <software crypto> on motherboard
pcib0 pcibus 0 on motherboard
pci0: <PCI bus> on pcib0
Geode LX: Soekris net5501 comBIOS ver. 1.33 20070103 Copyright (C) 2000-2007
pci0: <encrypt/decrypt, entertainment crypto> at device 1.2 (no driver attached)
vr0: <VIA VT6105M Rhine III 10/100BaseTX> port 0xe100-0xe1ff mem 0xa0004000-0xa00040ff irq 11 at device 6.0 on pci0
vr0: Quirks: 0x2
vr0: Revision: 0x96
miibus0: <MII bus> on vr0
ukphy0: <Generic IEEE 802.3u media interface> PHY 1 on miibus0
ukphy0:  none, 10baseT, 10baseT-FDX, 100baseTX, 100baseTX-FDX, auto, auto-flow
vr0: Ethernet address: 00:00:24:cc:93:44
vr0: [ITHREAD]
vr1: <VIA VT6105M Rhine III 10/100BaseTX> port 0xe200-0xe2ff mem 0xa0004100-0xa00041ff irq 5 at device 7.0 on pci0
vr1: Quirks: 0x2
vr1: Revision: 0x96
miibus1: <MII bus> on vr1
ukphy1: <Generic IEEE 802.3u media interface> PHY 1 on miibus1
ukphy1:  none, 10baseT, 10baseT-FDX, 100baseTX, 100baseTX-FDX, auto, auto-flow
vr1: Ethernet address: 00:00:24:cc:93:45
vr1: [ITHREAD]
vr2: <VIA VT6105M Rhine III 10/100BaseTX> port 0xe300-0xe3ff mem 0xa0004200-0xa00042ff irq 9 at device 8.0 on pci0
vr2: Quirks: 0x2
vr2: Revision: 0x96
miibus2: <MII bus> on vr2
ukphy2: <Generic IEEE 802.3u media interface> PHY 1 on miibus2
ukphy2:  none, 10baseT, 10baseT-FDX, 100baseTX, 100baseTX-FDX, auto, auto-flow
vr2: Ethernet address: 00:00:24:cc:93:46
vr2: [ITHREAD]
vr3: <VIA VT6105M Rhine III 10/100BaseTX> port 0xe400-0xe4ff mem 0xa0004300-0xa00043ff irq 12 at device 9.0 on pci0
vr3: Quirks: 0x2
vr3: Revision: 0x96
miibus3: <MII bus> on vr3
ukphy3: <Generic IEEE 802.3u media interface> PHY 1 on miibus3
ukphy3:  none, 10baseT, 10baseT-FDX, 100baseTX, 100baseTX-FDX, auto, auto-flow
vr3: Ethernet address: 00:00:24:cc:93:47
vr3: [ITHREAD]
isab0: <PCI-ISA bridge> at device 20.0 on pci0
isa0: <ISA bus> on isab0
atapci0: <AMD CS5536 UDMA100 controller> port 0x1f0-0x1f7,0x3f6,0x170-0x177,0x376,0xe000-0xe00f at device 20.2 on pci0
ata0: <ATA channel> at channel 0 on atapci0
ata0: [ITHREAD]
ata1: <ATA channel> at channel 1 on atapci0
ata1: [ITHREAD]
ohci0: <OHCI (generic) USB controller> mem 0xa0005000-0xa0005fff irq 15 at device 21.0 on pci0
ohci0: [ITHREAD]
usbus0 on ohci0
ehci0: <AMD CS5536 (Geode) USB 2.0 controller> mem 0xa0006000-0xa0006fff irq 15 at device 21.1 on pci0
ehci0: [ITHREAD]
usbus1: EHCI version 1.0
usbus1 on ehci0
cpu0 on motherboard
pmtimer0 on isa0
orm0: <ISA Option ROM> at iomem 0xc8000-0xd27ff pnpid ORM0000 on isa0
atkbdc0: <Keyboard controller (i8042)> at port 0x60,0x64 on isa0
atkbd0: <AT Keyboard> irq 1 on atkbdc0
kbd0 at atkbd0
atkbd0: [GIANT-LOCKED]
atkbd0: [ITHREAD]
atrtc0: <AT Real Time Clock> at port 0x70 irq 8 on isa0
ppc0: parallel port not found.
uart0: <16550 or compatible> at port 0x3f8-0x3ff irq 4 flags 0x10 on isa0
uart0: [FILTER]
uart0: console (19200,n,8,1)
uart1: <16550 or compatible> at port 0x2f8-0x2ff irq 3 on isa0
uart1: [FILTER]
Timecounter "TSC" frequency 499903982 Hz quality 800
Timecounters tick every 1.000 msec
IPsec: Initialized Security Association Processing.
usbus0: 12Mbps Full Speed USB v1.0
usbus1: 480Mbps High Speed USB v2.0
ad0: 76319MB <WDC WD800VE-00HDT0 09.07D09> at ata0-master UDMA100 
ugen0.1: <AMD> at usbus0
uhub0: <AMD OHCI root HUB, class 9/0, rev 1.00/1.00, addr 1> on usbus0
ugen1.1: <AMD> at usbus1
uhub1: <AMD EHCI root HUB, class 9/0, rev 2.00/1.00, addr 1> on usbus1
GEOM: ad0s1: geometry does not match label (255h,63s != 16h,63s).
uhub0: 4 ports with 4 removable, self powered
Root mount waiting for: usbus1
Root mount waiting for: usbus1
uhub1: 4 ports with 4 removable, self powered
Trying to mount root from ufs:/dev/ad0s1a
The last log rotation is from 2016: 
[root@roadkiller /var/log]# stat /var/log/wtmp      
65 61783 -rw-r--r-- 1 root wheel 208219 1056 "Nov  1 05:00:01 2016" "Jan 18 22:29:16 2017" "Jan 18 22:29:16 2017" "Nov  1 05:00:01 2016" 16384 4 0 /var/log/wtmp
Interestingly, I switched between eicat and teksavvy on December 11th. Which year? Who knows! 
Dec 11 16:38:40 roadkiller mpd: [eicatL0] LCP: authorization successful
Dec 11 16:41:15 roadkiller mpd: [teksavvyL0] LCP: authorization successful
Never realized those good old logs had a "oh dear forgot the year" issue (that's something like Y2K except just "Y", I guess). That was probably 2015, because the log dates from 2017, and the last entry is from November of the year after the above: 
[root@roadkiller /var/log]# stat mpd.log 
65 47113 -rw-r--r-- 1 root wheel 193008 71939195 "Jan 18 22:39:18 2017" "Jan 18 22:39:59 2017" "Jan 18 22:39:59 2017" "Apr  2 10:41:37 2013" 16384 140640 0 mpd.log
It looks like the system was installed in 2010: 
[root@roadkiller /var/log]# stat /
63 2 drwxr-xr-x 21 root wheel 2120 512 "Jan 18 22:34:43 2017" "Jan 18 22:28:12 2017" "Jan 18 22:28:12 2017" "Jul 18 22:25:00 2010" 16384 4 0 /
... so it lived for about 6 years, but still works after almost 14 years, which I find utterly amazing. Another amazing thing is that there's tuptime installed on that server! That is a software I thought I discovered later and then sponsored in Debian, but turns out I was already using it then! 
[root@roadkiller /var]# tuptime 
System startups:        19   since   21:20:16 11/07/15
System shutdowns:       0 ok   -   18 bad
System uptime:          85.93 %   -   1 year, 11 days, 10 hours, 3 minutes and 36 seconds
System downtime:        14.07 %   -   61 days, 15 hours, 22 minutes and 45 seconds
System life:            1 year, 73 days, 1 hour, 26 minutes and 20 seconds
Largest uptime:         122 days, 9 hours, 17 minutes and 6 seconds   from   08:17:56 02/02/16
Shortest uptime:        5 minutes and 4 seconds   from   21:55:00 01/18/17
Average uptime:         19 days, 19 hours, 28 minutes and 37 seconds
Largest downtime:       57 days, 1 hour, 9 minutes and 59 seconds   from   20:45:01 11/22/16
Shortest downtime:      -1 years, 364 days, 23 hours, 58 minutes and 12 seconds   from   22:30:01 01/18/17
Average downtime:       3 days, 5 hours, 51 minutes and 43 seconds
Current uptime:         18 minutes and 23 seconds   since   22:28:13 01/18/17
Actual up/down times: 
[root@roadkiller /var]# tuptime -t
No.        Startup Date                                         Uptime       Shutdown Date   End                                                  Downtime
1     21:20:16 11/07/15      1 day, 0 hours, 40 minutes and 12 seconds   22:00:28 11/08/15   BAD                                  2 minutes and 37 seconds
2     22:03:05 11/08/15      1 day, 9 hours, 41 minutes and 57 seconds   07:45:02 11/10/15   BAD                                  3 minutes and 24 seconds
3     07:48:26 11/10/15    20 days, 2 hours, 41 minutes and 34 seconds   10:30:00 11/30/15   BAD                        4 hours, 50 minutes and 21 seconds
4     15:20:21 11/30/15                      19 minutes and 40 seconds   15:40:01 11/30/15   BAD                                   6 minutes and 5 seconds
5     15:46:06 11/30/15                      53 minutes and 55 seconds   16:40:01 11/30/15   BAD                           1 hour, 1 minute and 38 seconds
6     17:41:39 11/30/15     6 days, 16 hours, 3 minutes and 22 seconds   09:45:01 12/07/15   BAD                4 days, 6 hours, 53 minutes and 11 seconds
7     16:38:12 12/11/15   50 days, 17 hours, 56 minutes and 49 seconds   10:35:01 01/31/16   BAD                                 10 minutes and 52 seconds
8     10:45:53 01/31/16     1 day, 21 hours, 28 minutes and 16 seconds   08:14:09 02/02/16   BAD                                  3 minutes and 48 seconds
9     08:17:56 02/02/16    122 days, 9 hours, 17 minutes and 6 seconds   18:35:02 06/03/16   BAD                                 10 minutes and 16 seconds
10    18:45:18 06/03/16   29 days, 17 hours, 14 minutes and 43 seconds   12:00:01 07/03/16   BAD                                 12 minutes and 34 seconds
11    12:12:35 07/03/16   31 days, 17 hours, 17 minutes and 26 seconds   05:30:01 08/04/16   BAD                                 14 minutes and 25 seconds
12    05:44:26 08/04/16     15 days, 1 hour, 55 minutes and 35 seconds   07:40:01 08/19/16   BAD                                  6 minutes and 51 seconds
13    07:46:52 08/19/16     7 days, 5 hours, 23 minutes and 10 seconds   13:10:02 08/26/16   BAD                                  3 minutes and 45 seconds
14    13:13:47 08/26/16   27 days, 21 hours, 36 minutes and 14 seconds   10:50:01 09/23/16   BAD                                  2 minutes and 14 seconds
15    10:52:15 09/23/16   60 days, 10 hours, 52 minutes and 46 seconds   20:45:01 11/22/16   BAD                 57 days, 1 hour, 9 minutes and 59 seconds
16    21:55:00 01/18/17                        5 minutes and 4 seconds   22:00:04 01/18/17   BAD                                 11 minutes and 15 seconds
17    22:11:19 01/18/17                       8 minutes and 42 seconds   22:20:01 01/18/17   BAD                                   1 minute and 20 seconds
18    22:21:21 01/18/17                       8 minutes and 40 seconds   22:30:01 01/18/17   BAD   -1 years, 364 days, 23 hours, 58 minutes and 12 seconds
19    22:28:13 01/18/17                      20 minutes and 17 seconds
The last few entries are actually the tests I'm running now, it seems this machine thinks we're now on 2017-01-18 at ~22:00, while we're actually 2024-01-24 at ~12:00 local: 
Wed Jan 18 23:05:38 EST 2017
FreeBSD/i386 (roadkiller.anarc.at) (ttyu0)
login: root
Password:
Jan 18 23:07:10 roadkiller login: ROOT LOGIN (root) ON ttyu0
Last login: Wed Jan 18 22:29:16 on ttyu0
Copyright (c) 1992-2013 The FreeBSD Project.
Copyright (c) 1979, 1980, 1983, 1986, 1988, 1989, 1991, 1992, 1993, 1994
        The Regents of the University of California. All rights reserved.
FreeBSD 8.4-RELEASE-p12 (ROADKILL) #5: Fri Jun  6 02:43:23 EDT 2014
Reminders:
 * commit stuff in /etc
 * reload firewall (in screen!):
    pfctl -f /etc/pf.conf ; sleep 1
 * vim + syn on makes pf.conf more readable
 * monitoring the PPPoE uplink:
   tail -f /var/log/mpd.log
Current problems:
 * sometimes pf doesn't start properly on boot, if pppoe failed to come up, use
   this to resume:
     /etc/rc.d/pf start
   it will kill your shell, but fix NAT (2012-08-10)
 * babel fails to start on boot (2013-06-15):
     babeld -D -g 33123 tap0 vr3
 * DNS often fails, tried messing with unbound.conf (2014-10-05) and updating
   named.root (2016-01-28) and performance tweaks (ee63689)
 * asterisk and mpd4 are deprecated and should be uninstalled when we're sure
   their replacements (voipms + ata and mpd5) are working (2015-01-13)
 * if IPv6 fails, it's because netblocks are not being routed upstream. DHCPcd
   should do this, but doesn't start properly, use this to resume (2015-12-21):
     /usr/local/sbin/dhcpcd -6 --persistent --background --timeout 0 -C resolv.conf ng0
This machine is doomed to be replaced with the new omnia router, Indiegogo
campaign should ship in april 2016: http://igg.me/at/turris-omnia/x
(I really like the motd I left myself there. In theory, I guess this could just start connecting to the internet again if I still had the same PPPoE/ADSL link I had almost a decade ago; obviously, I do not.) Not sure how the system figured the 2017 time: the onboard clock itself believes we're in 1980, so clearly the CMOS battery has (understandably) failed: 
> ?
comBIOS Monitor Commands
boot [drive][:partition] INT19 Boot
reboot                   cold boot
download                 download a file using XMODEM/CRC
flashupdate              update flash BIOS with downloaded file
time [HH:MM:SS]          show or set time
date [YYYY/MM/DD]        show or set date
d[b w d] [adr]           dump memory bytes/words/dwords
e[b w d] adr value [...] enter bytes/words/dwords
i[b w d] port            input from 8/16/32-bit port
o[b w d] port value      output to 8/16/32-bit port
run adr                  execute code at adr
cmosread [adr]           read CMOS RAM data
cmoswrite adr byte [...] write CMOS RAM data
cmoschecksum             update CMOS RAM Checksum
set parameter=value      set system parameter to value
show [parameter]         show one or all system parameters
?/help                   show this help
> show
ConSpeed = 19200
ConLock = Enabled
ConMute = Disabled
BIOSentry = Enabled
PCIROMS = Enabled
PXEBoot = Enabled
FLASH = Primary
BootDelay = 5
FastBoot = Disabled
BootPartition = Disabled
BootDrive = 80 81 F0 FF 
ShowPCI = Enabled
Reset = Hard
CpuSpeed = Default
> time
Current Date and Time is: 1980/01/01 00:56:47
Another bit of archeology: I had documented various outages with my ISP... back in 2003! 
[root@roadkiller ~/bin]# cat ppp_stats/downtimes.txt
11/03/2003 18:24:49 218
12/03/2003 09:10:49 118
12/03/2003 10:05:57 680
12/03/2003 10:14:50 106
12/03/2003 10:16:53 6
12/03/2003 10:35:28 146
12/03/2003 10:57:26 393
12/03/2003 11:16:35 5
12/03/2003 11:16:54 11
13/03/2003 06:15:57 18928
13/03/2003 09:43:36 9730
13/03/2003 10:47:10 23
13/03/2003 10:58:35 5
16/03/2003 01:32:36 338
16/03/2003 02:00:33 120
16/03/2003 11:14:31 14007
19/03/2003 00:56:27 11179
19/03/2003 00:56:43 5
19/03/2003 00:56:53 0
19/03/2003 00:56:55 1
19/03/2003 00:57:09 1
19/03/2003 00:57:10 1
19/03/2003 00:57:24 1
19/03/2003 00:57:25 1
19/03/2003 00:57:39 1
19/03/2003 00:57:40 1
19/03/2003 00:57:44 3
19/03/2003 00:57:53 0
19/03/2003 00:57:55 0
19/03/2003 00:58:08 0
19/03/2003 00:58:10 0
19/03/2003 00:58:23 0
19/03/2003 00:58:25 0
19/03/2003 00:58:39 1
19/03/2003 00:58:42 2
19/03/2003 00:58:58 5
19/03/2003 00:59:35 2
19/03/2003 00:59:47 3
19/03/2003 01:00:34 3
19/03/2003 01:00:39 0
19/03/2003 01:00:54 0
19/03/2003 01:01:11 2
19/03/2003 01:01:25 1
19/03/2003 01:01:48 1
19/03/2003 01:02:03 1
19/03/2003 01:02:10 2
19/03/2003 01:02:20 3
19/03/2003 01:02:44 3
19/03/2003 01:03:45 3
19/03/2003 01:04:39 2
19/03/2003 01:05:40 2
19/03/2003 01:06:35 2
19/03/2003 01:07:36 2
19/03/2003 01:08:31 2
19/03/2003 01:08:38 2
19/03/2003 01:10:07 3
19/03/2003 01:11:05 2
19/03/2003 01:12:03 3
19/03/2003 01:13:01 3
19/03/2003 01:13:58 2
19/03/2003 01:14:59 5
19/03/2003 01:15:54 2
19/03/2003 01:16:55 2
19/03/2003 01:17:50 2
19/03/2003 01:18:51 3
19/03/2003 01:19:46 2
19/03/2003 01:20:46 2
19/03/2003 01:21:42 3
19/03/2003 01:22:42 3
19/03/2003 01:23:37 2
19/03/2003 01:24:38 3
19/03/2003 01:25:33 2
19/03/2003 01:26:33 2
19/03/2003 01:27:30 3
19/03/2003 01:28:55 2
19/03/2003 01:29:56 2
19/03/2003 01:30:50 2
19/03/2003 01:31:42 3
19/03/2003 01:32:36 3
19/03/2003 01:33:27 2
19/03/2003 01:34:21 2
19/03/2003 01:35:22 2
19/03/2003 01:36:17 3
19/03/2003 01:37:18 2
19/03/2003 01:38:13 3
19/03/2003 01:39:39 2
19/03/2003 01:40:39 2
19/03/2003 01:41:35 3
19/03/2003 01:42:35 3
19/03/2003 01:43:31 3
19/03/2003 01:44:31 3
19/03/2003 01:45:53 3
19/03/2003 01:46:48 3
19/03/2003 01:47:48 2
19/03/2003 01:48:44 3
19/03/2003 01:49:44 2
19/03/2003 01:50:40 3
19/03/2003 01:51:39 1
19/03/2003 11:04:33 19   
19/03/2003 18:39:36 2833 
19/03/2003 18:54:05 825  
19/03/2003 19:04:00 454  
19/03/2003 19:08:11 210  
19/03/2003 19:41:44 272  
19/03/2003 21:18:41 208  
24/03/2003 04:51:16 6
27/03/2003 04:51:20 5
30/03/2003 04:51:25 5
31/03/2003 08:30:31 255  
03/04/2003 08:30:36 5
06/04/2003 01:16:00 621  
06/04/2003 22:18:08 17   
06/04/2003 22:32:44 13   
09/04/2003 22:33:12 28   
12/04/2003 22:33:17 6
15/04/2003 22:33:22 5
17/04/2003 15:03:43 18   
20/04/2003 15:03:48 5
23/04/2003 15:04:04 16   
23/04/2003 21:08:30 339  
23/04/2003 21:18:08 13   
23/04/2003 23:34:20 253  
26/04/2003 23:34:45 25   
29/04/2003 23:34:49 5
02/05/2003 13:10:01 185  
05/05/2003 13:10:06 5
08/05/2003 13:10:11 5
09/05/2003 14:00:36 63928
09/05/2003 16:58:52 2
11/05/2003 23:08:48 2
14/05/2003 23:08:53 6
17/05/2003 23:08:58 5
20/05/2003 23:09:03 5
23/05/2003 23:09:08 5
26/05/2003 23:09:14 5
29/05/2003 23:00:10 3
29/05/2003 23:03:01 10   
01/06/2003 23:03:05 4
04/06/2003 23:03:10 5
07/06/2003 23:03:38 28   
10/06/2003 23:03:50 12   
13/06/2003 23:03:55 6
14/06/2003 07:42:20 3
14/06/2003 14:37:08 3
15/06/2003 20:08:34 3
18/06/2003 20:08:39 6
21/06/2003 20:08:45 6
22/06/2003 03:05:19 138  
22/06/2003 04:06:28 3
25/06/2003 04:06:58 31   
28/06/2003 04:07:02 4
01/07/2003 04:07:06 4
04/07/2003 04:07:11 5
07/07/2003 04:07:16 5
12/07/2003 04:55:20 6
12/07/2003 19:09:51 1158 
12/07/2003 22:14:49 8025 
15/07/2003 22:14:54 6
16/07/2003 05:43:06 18   
19/07/2003 05:43:12 6
22/07/2003 05:43:17 5
23/07/2003 18:18:55 183  
23/07/2003 18:19:55 9
23/07/2003 18:29:15 158  
23/07/2003 19:48:44 4604 
23/07/2003 20:16:27 3
23/07/2003 20:37:29 1079 
23/07/2003 20:43:12 342  
23/07/2003 22:25:51 6158
Fascinating. I suspect the (IDE!) hard drive might be failing as I saw two new files created in /var that I didn't remember seeing before: 
-rw-r--r--   1 root    wheel        0 Jan 18 22:55 3@T3
-rw-r--r--   1 root    wheel        0 Jan 18 22:55 DY5
So I shutdown the machine, possibly for the last time: 
Waiting (max 60 seconds) for system process  bufdaemon' to stop...done
Waiting (max 60 seconds) for system process  syncer' to stop...
Syncing disks, vnodes remaining...3 3 0 1 1 0 0 done
All buffers synced.
Uptime: 36m43s
usbus0: Controller shutdown
uhub0: at usbus0, port 1, addr 1 (disconnected)
usbus0: Controller shutdown complete
usbus1: Controller shutdown
uhub1: at usbus1, port 1, addr 1 (disconnected)
usbus1: Controller shutdown complete
The operating system has halted.
Please press any key to reboot.
I'll finally note this was the last FreeBSD server I personally operated. I also used FreeBSD to setup the core routers at Koumbit but those were replaced with Debian recently as well. Thanks Soekris, that was some sturdy hardware. Hopefully this new Protectli router will live up to that "decade plus" challenge. Not sure what the fate of this device will be: I'll bring it to the next Montreal Debian & Stuff to see if anyone's interested, contact me if you can't show up and want this thing.

29 January 2024

Michael Ablassmeier: qmpbackup 0.28

Over the last weekend i had some spare time to improve qmpbackup a little more, the new version: and some minor code reworks. Hope its useful for someone.

26 January 2024

Bastian Venthur: Investigating popularity of Python build backends over time

Inspired by a Mastodon post by Fran oise Conil, who investigated the current popularity of build backends used in pyproject.toml files, I wanted to investigate how the popularity of build backends used in pyproject.toml files evolved over the years since the introduction of PEP-0517 in 2015. Getting the data Tom Forbes provides a huge dataset that contains information about every file within every release uploaded to PyPI. To get the current dataset, we can use: 
curl -L --remote-name-all $(curl -L "https://github.com/pypi-data/data/raw/main/links/dataset.txt")
This will download approximately 30GB of parquet files, providing detailed information about each file included in a PyPI upload, including:
  1. project name, version and release date
  2. file path, size and line count
  3. hash of the file
The dataset does not contain the actual files themselves though, more on that in a moment. Querying the dataset using duckdb We can now use duckdb to query the parquet files directly. Let s look into the schema first: 
describe select * from '*.parquet';
 
    column_name     column_type    null    
      varchar         varchar     varchar  
 
  project_name      VARCHAR       YES      
  project_version   VARCHAR       YES      
  project_release   VARCHAR       YES      
  uploaded_on       TIMESTAMP     YES      
  path              VARCHAR       YES      
  archive_path      VARCHAR       YES      
  size              UBIGINT       YES      
  hash              BLOB          YES      
  skip_reason       VARCHAR       YES      
  lines             UBIGINT       YES      
  repository        UINTEGER      YES      
 
  11 rows                       6 columns
From all files mentioned in the dataset, we only care about pyproject.toml files that are in the project s root directory. Since we ll still have to download the actual files, we need to get the path and the repository to construct the corresponding URL to the mirror that contains all files in a bunch of huge git repositories. Some files are not available on the mirrors; to skip these, we only take files where the skip_reason is empty. We also care about the timestamp of the upload (uploaded_on) and the hash to avoid processing identical files twice: 
select
    path,
    hash,
    uploaded_on,
    repository
from '*.parquet'
where
    skip_reason == '' and
    lower(string_split(path, '/')[-1]) == 'pyproject.toml' and
    len(string_split(path, '/')) == 5
order by uploaded_on desc
This query runs for a few minutes on my laptop and returns ~1.2M rows. Getting the actual files Using the repository and path, we can now construct an URL from which we can fetch the actual file for further processing: 
url = f"https://raw.githubusercontent.com/pypi-data/pypi-mirror- repository /code/ path "
We can download the individual pyproject.toml files and parse them to read the build-backend into a dictionary mapping the file-hash to the build backend. Downloads on GitHub are rate-limited, so downloading 1.2M files will take a couple of days. By skipping files with a hash we ve already processed, we can avoid downloading the same file more than once, cutting the required downloads by circa 50%. Results Assuming the data is complete and my analysis is sound, these are the findings: There is a surprising amount of build backends in use, but the overall amount of uploads per build backend decreases quickly, with a long tail of single uploads: 
>>> results.backend.value_counts()
backend
setuptools        701550
poetry            380830
hatchling          56917
flit               36223
pdm                11437
maturin             9796
jupyter             1707
mesonpy              625
scikit               556
                   ...
postry                 1
tree                   1
setuptoos              1
neuron                 1
avalon                 1
maturimaturinn         1
jsonpath               1
ha                     1
pyo3                   1
Name: count, Length: 73, dtype: int64
We pick only the top 4 build backends, and group the remaining ones (including PDM and Maturin) into other so they are accounted for as well. The following plot shows the relative distribution of build backends over time. Each bin represents a time span of 28 days. I chose 28 days to reduce visual clutter. Within each bin, the height of the bars corresponds to the relative proportion of uploads during that time interval: Relative distribution of build backends over time Looking at the right side of the plot, we see the current distribution. It confirms Fran oise s findings about the current popularity of build backends: Between 2018 and 2020 the graph exhibits significant fluctuations, due to the relatively low amount uploads utizing pyproject.toml files. During that early period, Flit started as the most popular build backend, but was eventually displaced by Setuptools and Poetry. Between 2020 and 2020, the overall usage of pyproject.toml files increased significantly. By the end of 2022, the share of Setuptools peaked at 70%. After 2020, other build backends experienced a gradual rise in popularity. Amongh these, Hatch emerged as a notable contender, steadily gaining traction and ultimately stabilizing at 10%. We can also look into the absolute distribution of build backends over time: Absolute distribution of build backends over time The plot shows that Setuptools has the strongest growth trajectory, surpassing all other build backends. Poetry and Hatch are growing at a comparable rate, but since Hatch started roughly 4 years after Poetry, it s lagging behind in popularity. Despite not being among the most widely used backends anymore, Flit maintains a steady and consistent growth pattern, indicating its enduring relevance in the Python packaging landscape. The script for downloading and analyzing the data can be found in my GitHub repository. It contains the results of the duckb query (so you don t have to download the full dataset) and the pickled dictionary, mapping the file hashes to the build backends, saving you days for downloading and analyzing the pyproject.toml files yourself.

25 January 2024

Dimitri John Ledkov: Ubuntu Livepatch service now supports over 60 different kernels

Linux kernel getting a livepatch whilst running a marathon. Generated with AI.
Livepatch service eliminates the need for unplanned maintenance windows for high and critical severity kernel vulnerabilities by patching the Linux kernel while the system runs. Originally the service launched in 2016 with just a single kernel flavour supported.Over the years, additional kernels were added: new LTS releases, ESM kernels, Public Cloud kernels, and most recently HWE kernels too.Recently livepatch support was expanded for FIPS compliant kernels, Public cloud FIPS compliant kernels, and as well IBM Z (mainframe) kernels. Bringing the total of kernel flavours support to over 60 distinct kernel flavours supported in parallel. The table of supported kernels in the documentation lists the supported kernel flavours ABIs, the duration of individual build's support window, supported architectures, and the Ubuntu release. This work was only possible thanks to the collaboration with the Ubuntu Certified Public Cloud team, engineers at IBM for IBM Z (s390x) support, Ubuntu Pro team, Livepatch server & client teams.It is a great milestone, and I personally enjoy seeing the non-intrusive popup on my Ubuntu Desktop that a kernel livepatch was applied to my running system. I do enable Ubuntu Pro on my personal laptop thanks to the free Ubuntu Pro subscription for individuals.What's next? The next frontier is supporting ARM64 kernels. The Canonical kernel team has completed the gap analysis to start supporting Livepatch Service for ARM64. Upstream Linux requires development work on the consistency model to fully support livepatch on ARM64 processors. Livepatch code changes are applied on a per-task basis, when the task is deemed safe to switch over. This safety check depends mostly on kernel stacktraces. For these checks, CONFIG_HAVE_RELIABLE_STACKTRACE needs to be available in the upstream ARM64 kernel. (see The Linux Kernel Documentation). There are preliminary patches that enable reliable stacktraces on ARM64, however these turned out to be problematic as there are lots of fix revisions that came after the initial patchset that AWS ships with 5.10. This is a call for help from any interested parties. If you have engineering resources and are interested in bringing Livepatch Service to your ARM64 platforms, please reach out to the Canonical Kernel team on the public Ubuntu Matrix, Discourse, and mailing list. If you want to chat in person, see you at FOSDEM next weekend.

Joachim Breitner: GHC Steering Committee Retrospective

After seven years of service as member and secretary on the GHC Steering Committee, I have resigned from that role. So this is a good time to look back and retrace the formation of the GHC proposal process and committee. In my memory, I helped define and shape the proposal process, optimizing it for effectiveness and throughput, but memory can be misleading, and judging from the paper trail in my email archives, this was indeed mostly Ben Gamari s and Richard Eisenberg s achievement: Already in Summer of 2016, Ben Gamari set up the ghc-proposals Github repository with a sketch of a process and sent out a call for nominations on the GHC user s mailing list, which I replied to. The Simons picked the first set of members, and in the fall of 2016 we discussed the committee s by-laws and procedures. As so often, Richard was an influential shaping force here.

Three ingredients For example, it was him that suggested that for each proposal we have one committee member be the Shepherd , overseeing the discussion. I believe this was one ingredient for the process effectiveness: There is always one person in charge, and thus we avoid the delays incurred when any one of a non-singleton set of volunteers have to do the next step (and everyone hopes someone else does it). The next ingredient was that we do not usually require a vote among all members (again, not easy with volunteers with limited bandwidth and occasional phases of absence). Instead, the shepherd makes a recommendation (accept/reject), and if the other committee members do not complain, this silence is taken as consent, and we come to a decision. It seems this idea can also be traced back on Richard, who suggested that once a decision is requested, the shepherd [generates] consensus. If consensus is elusive, then we vote. At the end of the year we agreed and wrote down these rules, created the mailing list for our internal, but publicly archived committee discussions, and began accepting proposals, starting with Adam Gundry s OverloadedRecordFields. At that point, there was no secretary role yet, so how I did become one? It seems that in February 2017 I started to clean-up and refine the process documentation, fixing bugs in the process (like requiring authors to set Github labels when they don t even have permissions to do that). This in particular meant that someone from the committee had to manually handle submissions and so on, and by the aforementioned principle that at every step there ought to be exactly one person in change, the role of a secretary followed naturally. In the email in which I described that role I wrote:
Simon already shoved me towards picking up the secretary hat, to reduce load on Ben.
So when I merged the updated process documentation, I already listed myself secretary . It wasn t just Simon s shoving that put my into the role, though. I dug out my original self-nomination email to Ben, and among other things I wrote:
I also hope that there is going to be clear responsibilities and a clear workflow among the committee. E.g. someone (possibly rotating), maybe called the secretary, who is in charge of having an initial look at proposals and then assigning it to a member who shepherds the proposal.
So it is hardly a surprise that I became secretary, when it was dear to my heart to have a smooth continuous process here. I am rather content with the result: These three ingredients single secretary, per-proposal shepherds, silence-is-consent helped the committee to be effective throughout its existence, even as every once in a while individual members dropped out.

Ulterior motivation I must admit, however, there was an ulterior motivation behind me grabbing the secretary role: Yes, I did want the committee to succeed, and I did want that authors receive timely, good and decisive feedback on their proposals but I did not really want to have to do that part. I am, in fact, a lousy proposal reviewer. I am too generous when reading proposals, and more likely mentally fill gaps in a specification rather than spotting them. Always optimistically assuming that the authors surely know what they are doing, rather than critically assessing the impact, the implementation cost and the interaction with other language features. And, maybe more importantly: why should I know which changes are good and which are not so good in the long run? Clearly, the authors cared enough about a proposal to put it forward, so there is some need and I do believe that Haskell should stay an evolving and innovating language but how does this help me decide about this or that particular feature. I even, during the formation of the committee, explicitly asked that we write down some guidance on Vision and Guideline ; do we want to foster change or innovation, or be selective gatekeepers? Should we accept features that are proven to be useful, or should we accept features so that they can prove to be useful? This discussion, however, did not lead to a concrete result, and the assessment of proposals relied on the sum of each member s personal preference, expertise and gut feeling. I am not saying that this was a mistake: It is hard to come up with a general guideline here, and even harder to find one that does justice to each individual proposal. So the secret motivation for me to grab the secretary post was that I could contribute without having to judge proposals. Being secretary allowed me to assign most proposals to others to shepherd, and only once in a while myself took care of a proposal, when it seemed to be very straight-forward. Sneaky, ain t it?

7 Years later For years to come I happily played secretary: When an author finished their proposal and public discussion ebbed down they would ping me on GitHub, I would pick a suitable shepherd among the committee and ask them to judge the proposal. Eventually, the committee would come to a conclusion, usually by implicit consent, sometimes by voting, and I d merge the pull request and update the metadata thereon. Every few months I d summarize the current state of affairs to the committee (what happened since the last update, which proposals are currently on our plate), and once per year gathered the data for Simon Peyton Jones annually GHC Status Report. Sometimes some members needed a nudge or two to act. Some would eventually step down, and I d sent around a call for nominations and when the nominations came in, distributed them off-list among the committee and tallied the votes. Initially, that was exciting. For a long while it was a pleasant and rewarding routine. Eventually, it became a mere chore. I noticed that I didn t quite care so much anymore about some of the discussion, and there was a decent amount of naval-gazing, meta-discussions and some wrangling about claims of authority that was probably useful and necessary, but wasn t particularly fun. I also began to notice weaknesses in the processes that I helped shape: We could really use some more automation for showing proposal statuses, notifying people when they have to act, and nudging them when they don t. The whole silence-is-assent approach is good for throughput, but not necessary great for quality, and maybe the committee members need to be pushed more firmly to engage with each proposal. Like GHC itself, the committee processes deserve continuous refinement and refactoring, and since I could not muster the motivation to change my now well-trod secretarial ways, it was time for me to step down. Luckily, Adam Gundry volunteered to take over, and that makes me feel much less bad for quitting. Thanks for that! And although I am for my day job now enjoying a language that has many of the things out of the box that for Haskell are still only language extensions or even just future proposals (dependent types, BlockArguments, do notation with ( foo) expressions and Unicode), I m still around, hosting the Haskell Interlude Podcast, writing on this blog and hanging out at ZuriHac etc.

22 January 2024

Paul Tagliamonte: Writing a simulator to check phased array beamforming

Interested in future updates? Follow me on mastodon at @paul@soylent.green. Posts about hz.tools will be tagged #hztools.

If you're on the Fediverse, I'd very much appreciate boosts on my toot!
While working on hz.tools, I started to move my beamforming code from 2-D (meaning, beamforming to some specific angle on the X-Y plane for waves on the X-Y plane) to 3-D. I ll have more to say about that once I get around to publishing the code as soon as I m sure it s not completely wrong, but in the meantime I decided to write a simple simulator to visually check the beamformer against the textbooks. The results were pretty rad, so I figured I d throw together a post since it s interesting all on its own outside of beamforming as a general topic. I figured I d write this in Rust, since I ve been using Rust as my primary language over at zoo, and it s a good chance to learn the language better.
This post has some large GIFs

It make take a little bit to load depending on your internet connection. Sorry about that, I'm not clever enough to do better without doing tons of complex engineering work. They may be choppy while they load or something. I tried to compress an ensmall them, so if they're loaded but fuzzy, click on them to load a slightly larger version.
This post won t cover the basics of how phased arrays work or the specifics of calculating the phase offsets for each antenna, but I ll dig into how I wrote a simple simulator and how I wound up checking my phase offsets to generate the renders below.

Assumptions I didn t want to build a general purpose RF simulator, anything particularly generic, or something that would solve for any more than the things right in front of me. To do this as simply (and quickly all this code took about a day to write, including the beamforming math) I had to reduce the amount of work in front of me. Given that I was concerend with visualizing what the antenna pattern would look like in 3-D given some antenna geometry, operating frequency and configured beam, I made the following assumptions: All anetnnas are perfectly isotropic they receive a signal that is exactly the same strength no matter what direction the signal originates from. There s a single point-source isotropic emitter in the far-field (I modeled this as being 1 million meters away 1000 kilometers) of the antenna system. There is no noise, multipath, loss or distortion in the signal as it travels through space. Antennas will never interfere with each other.

2-D Polar Plots The last time I wrote something like this, I generated 2-D GIFs which show a radiation pattern, not unlike the polar plots you d see on a microphone. These are handy because it lets you visualize what the directionality of the antenna looks like, as well as in what direction emissions are captured, and in what directions emissions are nulled out. You can see these plots on spec sheets for antennas in both 2-D and 3-D form. Now, let s port the 2-D approach to 3-D and see how well it works out.

Writing the 3-D simulator As an EM wave travels through free space, the place at which you sample the wave controls that phase you observe at each time-step. This means, assuming perfectly synchronized clocks, a transmitter and receiver exactly one RF wavelength apart will observe a signal in-phase, but a transmitter and receiver a half wavelength apart will observe a signal 180 degrees out of phase. This means that if we take the distance between our point-source and antenna element, divide it by the wavelength, we can use the fractional part of the resulting number to determine the phase observed. If we multiply that number (in the range of 0 to just under 1) by tau, we can generate a complex number by taking the cos and sin of the multiplied phase (in the range of 0 to tau), assuming the transmitter is emitting a carrier wave at a static amplitude and all clocks are in perfect sync. 
 let observed_phases: Vec<Complex> = antennas
.iter()
.map( antenna   
let distance = (antenna - tx).magnitude();
let distance = distance - (distance as i64 as f64);
((distance / wavelength) * TAU)
 )
.map( phase  Complex(phase.cos(), phase.sin()))
.collect();
At this point, given some synthetic transmission point and each antenna, we know what the expected complex sample would be at each antenna. At this point, we can adjust the phase of each antenna according to the beamforming phase offset configuration, and add up every sample in order to determine what the entire system would collectively produce a sample as. 
 let beamformed_phases: Vec<Complex> = ...;
let magnitude = beamformed_phases
.iter()
.zip(observed_phases.iter())
.map( (beamformed, observed)  observed * beamformed)
.reduce( acc, el  acc + el)
.unwrap()
.abs();
Armed with this information, it s straight forward to generate some number of (Azimuth, Elevation) points to sample, generate a transmission point far away in that direction, resolve what the resulting Complex sample would be, take its magnitude, and use that to create an (x, y, z) point at (azimuth, elevation, magnitude). The color attached two that point is based on its distance from (0, 0, 0). I opted to use the Life Aquatic table for this one. After this process is complete, I have a point cloud of ((x, y, z), (r, g, b)) points. I wrote a small program using kiss3d to render point cloud using tons of small spheres, and write out the frames to a set of PNGs, which get compiled into a GIF. Now for the fun part, let s take a look at some radiation patterns!

1x4 Phased Array The first configuration is a phased array where all the elements are in perfect alignment on the y and z axis, and separated by some offset in the x axis. This configuration can sweep 180 degrees (not the full 360), but can t be steared in elevation at all. Let s take a look at what this looks like for a well constructed 1x4 phased array: And now let s take a look at the renders as we play with the configuration of this array and make sure things look right. Our initial quarter-wavelength spacing is very effective and has some outstanding performance characteristics. Let s check to see that everything looks right as a first test. Nice. Looks perfect. When pointing forward at (0, 0), we d expect to see a torus, which we do. As we sweep between 0 and 360, astute observers will notice the pattern is mirrored along the axis of the antennas, when the beam is facing forward to 0 degrees, it ll also receive at 180 degrees just as strong. There s a small sidelobe that forms when it s configured along the array, but it also becomes the most directional, and the sidelobes remain fairly small.

Long compared to the wavelength (1 ) Let s try again, but rather than spacing each antenna of a wavelength apart, let s see about spacing each antenna 1 of a wavelength apart instead. The main lobe is a lot more narrow (not a bad thing!), but some significant sidelobes have formed (not ideal). This can cause a lot of confusion when doing things that require a lot of directional resolution unless they re compensated for.

Going from ( to 5 ) The last model begs the question - what do things look like when you separate the antennas from each other but without moving the beam? Let s simulate moving our antennas but not adjusting the configured beam or operating frequency. Very cool. As the spacing becomes longer in relation to the operating frequency, we can see the sidelobes start to form out of the end of the antenna system.

2x2 Phased Array The second configuration I want to try is a phased array where the elements are in perfect alignment on the z axis, and separated by a fixed offset in either the x or y axis by their neighbor, forming a square when viewed along the x/y axis. Let s take a look at what this looks like for a well constructed 2x2 phased array: Let s do the same as above and take a look at the renders as we play with the configuration of this array and see what things look like. This configuration should suppress the sidelobes and give us good performance, and even give us some amount of control in elevation while we re at it. Sweet. Heck yeah. The array is quite directional in the configured direction, and can even sweep a little bit in elevation, a definite improvement from the 1x4 above.

Long compared to the wavelength (1 ) Let s do the same thing as the 1x4 and take a look at what happens when the distance between elements is long compared to the frequency of operation say, 1 of a wavelength apart? What happens to the sidelobes given this spacing when the frequency of operation is much different than the physical geometry? Mesmerising. This is my favorate render. The sidelobes are very fun to watch come in and out of existence. It looks absolutely other-worldly.

Going from ( to 5 ) Finally, for completeness' sake, what do things look like when you separate the antennas from each other just as we did with the 1x4? Let s simulate moving our antennas but not adjusting the configured beam or operating frequency. Very very cool. The sidelobes wind up turning the very blobby cardioid into an electromagnetic dog toy. I think we ve proven to ourselves that using a phased array much outside its designed frequency of operation seems like a real bad idea.

Future Work Now that I have a system to test things out, I m a bit more confident that my beamforming code is close to right! I d love to push that code over the line and blog about it, since it s a really interesting topic on its own. Once I m sure the code involved isn t full of lies, I ll put it up on the hztools org, and post about it here and on mastodon.

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