Search Results: "elf"

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).

4 March 2024

Colin Watson: Free software activity in January/February 2024

Two months into my new gig and it s going great! Tracking my time has taken a bit of getting used to, but having something that amounts to a queryable database of everything I ve done has also allowed some helpful introspection. Freexian sponsors up to 20% of my time on Debian tasks of my choice. In fact I ve been spending the bulk of my time on debusine which is itself intended to accelerate work on Debian, but more details on that later. While I contribute to Freexian s summaries now, I ve also decided to start writing monthly posts about my free software activity as many others do, to get into some more detail. January 2024 February 2024

3 March 2024

Dirk Eddelbuettel: RcppArmadillo 0.12.8.1.0 on CRAN: Upstream Fix, Interface Polish

armadillo image Armadillo is a powerful and expressive C++ template library for linear algebra and scientific computing. It aims towards a good balance between speed and ease of use, has a syntax deliberately close to Matlab, and is useful for algorithm development directly in C++, or quick conversion of research code into production environments. RcppArmadillo integrates this library with the R environment and language and is widely used by (currently) 1130 other packages on CRAN, downloaded 32.8 million times (per the partial logs from the cloud mirrors of CRAN), and the CSDA paper (preprint / vignette) by Conrad and myself has been cited 578 times according to Google Scholar. This release brings a new upstream bugfix release Armadillo 12.8.1 prepared by Conrad yesterday. It was delayed for a few hours as CRAN noticed an error in one package which we all concluded was spurious as it could be reproduced outside of the one run there. Following from the previous release, we also use the slighty faster Lighter header in the examples. And once it got to CRAN I also updated the Debian package. The set of changes since the last CRAN release follows.

Changes in RcppArmadillo version 0.12.8.1.0 (2024-03-02)
  • Upgraded to Armadillo release 12.8.1 (Cortisol Injector)
    • Workaround in norm() for yet another bug in macOS accelerate framework
  • Update README for RcppArmadillo usage counts
  • Update examples to use '#include <RcppArmadillo/Lighter>' for faster compilation excluding unused Rcpp features

Courtesy of my CRANberries, there is a diffstat report relative to previous release. More detailed information is on the RcppArmadillo page. Questions, comments etc should go to the rcpp-devel mailing list off the Rcpp R-Forge page. If you like this or other open-source work I do, you can sponsor me at GitHub.

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

26 February 2024

Sergio Durigan Junior: Planning to orphan Pagure on Debian

I have been thinking more and more about orphaning the Pagure Debian package. I don t have the time to maintain it properly anymore, and I have also lost interest in doing so.

What s Pagure Pagure is a git forge written entirely in Python using pygit2. It was almost entirely developed by one person, Pierre-Yves Chibon. He is (was?) a Red Hat employee and started working on this new git forge almost 10 years ago because the company wanted to develop something in-house for Fedora. The software is amazing and I admire Pierre-Yves quite a lot for what he was able to achieve basically alone. Unfortunately, a few years ago Fedora decided to move to Gitlab and the Pagure development pretty much stalled.

Pagure in Debian Packaging Pagure for Debian was hard, but it was also very fun. I learned quite a bit about many things (packaging and non-packaging related), interacted with the upstream community, decided to dogfood my own work and run my Pagure instance for a while, and tried to get newcomers to help me with the package (without much success, unfortunately). I remember that when I had started to package Pagure, Debian was also moving away from Alioth and discussing options. For a brief moment Pagure was a contender, but in the end the community decided to self-host Gitlab, and that s why we have Salsa now. I feel like I could have tipped the scales in favour of Pagure had I finished packaging it for Debian before the decision was made, but then again, to the best of my knowledge Salsa doesn t use our Gitlab package anyway

Are you interested in maintaining it? If you re interested in maintaining the package, please get in touch with me. I will happily pass the torch to someone else who is still using the software and wants to keep it healthy in Debian. If there is nobody interested, then I will just orphan it.

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

Jacob Adams: AAC and Debian

Currently, in a default installation of Debian with the GNOME desktop, Bluetooth headphones that require the AAC codec1 cannot be used. As the Debian wiki outlines, using the AAC codec over Bluetooth, while technically supported by PipeWire, is explicitly disabled in Debian at this time. This is because the fdk-aac library needed to enable this support is currently in the non-free component of the repository, meaning that PipeWire, which is in the main component, cannot depend on it.

How to Fix it Yourself If what you, like me, need is simply for Bluetooth Audio to work with AAC in Debian s default desktop environment2, then you ll need to rebuild the pipewire package to include the AAC codec. While the current version in Debian main has been built with AAC deliberately disabled, it is trivial to enable if you can install a version of the fdk-aac library. I preface this with the usual caveats when it comes to patent and licensing controversies. I am not a lawyer, building this package and/or using it could get you into legal trouble. These instructions have only been tested on an up-to-date copy of Debian 12.
  1. Install pipewire s build dependencies 
    sudo apt install build-essential devscripts
sudo apt build-dep pipewire
  2. Install libfdk-aac-dev 
    sudo apt install libfdk-aac-dev
    If the above doesn t work you ll likely need to enable non-free and try again 
    sudo sed -i 's/main/main non-free/g' /etc/apt/sources.list
sudo apt update
    Alternatively, if you wish to ensure you are maximally license-compliant and patent un-infringing3, you can instead build fdk-aac-free which includes only those components of AAC that are known to be patent-free3. This is what should eventually end up in Debian to resolve this problem (see below). 
    sudo apt install git-buildpackage
mkdir fdk-aac-source
cd fdk-aac-source
git clone https://salsa.debian.org/multimedia-team/fdk-aac
cd fdk-aac
gbp buildpackage
sudo dpkg -i ../libfdk-aac2_*deb ../libfdk-aac-dev_*deb
  3. Get the pipewire source code 
    mkdir pipewire-source
cd pipewire-source
apt source pipewire
    This will create a bunch of files within the pipewire-source directory, but you ll only need the pipewire-<version> folder, this contains all the files you ll need to build the package, with all the debian-specific patches already applied. Note that you don t want to run the apt source command as root, as it will then create files that your regular user cannot edit.
  4. Fix the dependencies and build options To fix up the build scripts to use the fdk-aac library, you need to save the following as pipewire-source/aac.patch 
    --- debian/control.orig
+++ debian/control
@@ -40,8 +40,8 @@
             modemmanager-dev,
             pkg-config,
             python3-docutils,
-               systemd [linux-any]
-Build-Conflicts: libfdk-aac-dev
+               systemd [linux-any],
+               libfdk-aac-dev
 Standards-Version: 4.6.2
 Vcs-Browser: https://salsa.debian.org/utopia-team/pipewire
 Vcs-Git: https://salsa.debian.org/utopia-team/pipewire.git
--- debian/rules.orig
+++ debian/rules
@@ -37,7 +37,7 @@
 		-Dauto_features=enabled \
 		-Davahi=enabled \
 		-Dbluez5-backend-native-mm=enabled \
-		-Dbluez5-codec-aac=disabled \
+		-Dbluez5-codec-aac=enabled \
 		-Dbluez5-codec-aptx=enabled \
 		-Dbluez5-codec-lc3=enabled \
 		-Dbluez5-codec-lc3plus=disabled \
    Then you ll need to run patch from within the pipewire-<version> folder created by apt source: 
    patch -p0 < ../aac.patch
  5. Build pipewire 
    cd pipewire-*
debuild
    Note that you will likely see an error from debsign at the end of this process, this is harmless, you simply don t have a GPG key set up to sign your newly-built package4. Packages don t need to be signed to be installed, and debsign uses a somewhat non-standard signing process that dpkg does not check anyway.
  1. Install libspa-0.2-bluetooth 
    sudo dpkg -i libspa-0.2-bluetooth_*.deb
  2. Restart PipeWire and/or Reboot 
    sudo reboot
    Theoretically there s a set of services to restart here that would get pipewire to pick up the new library, probably just pipewire itself. But it s just as easy to restart and ensure everything is using the correct library.

Why This is a slightly unusual situation, as the fdk-aac library is licensed under what even the GNU project acknowledges is a free software license. However, this license explicitly informs the user that they need to acquire a patent license to use this software5:
3. NO PATENT LICENSE NO EXPRESS OR IMPLIED LICENSES TO ANY PATENT CLAIMS, including without limitation the patents of Fraunhofer, ARE GRANTED BY THIS SOFTWARE LICENSE. Fraunhofer provides no warranty of patent non-infringement with respect to this software. You may use this FDK AAC Codec software or modifications thereto only for purposes that are authorized by appropriate patent licenses.
To quote the GNU project:
Because of this, and because the license author is a known patent aggressor, we encourage you to be careful about using or redistributing software under this license: you should first consider whether the licensor might aim to lure you into patent infringement.
AAC is covered by a number of patents, which expire at some point in the 2030s6. As such the current version of the library is potentially legally dubious to ship with any other software, as it could be considered patent-infringing3.

Fedora s solution Since 2017, Fedora has included a modified version of the library as fdk-aac-free, see the announcement and the bugzilla bug requesting review. This version of the library includes only the AAC LC profile, which is believed to be entirely patent-free3. Based on this, there is an open bug report in Debian requesting that the fdk-aac package be moved to the main component and that the pipwire package be updated to build against it.

The Debian NEW queue To resolve these bugs, a version of fdk-aac-free has been uploaded to Debian by Jeremy Bicha. However, to make it into Debian proper, it must first pass through the ftpmaster s NEW queue. The current version of fdk-aac-free has been in the NEW queue since July 2023. Based on conversations in some of the bugs above, it s been there since at least 20227. I hope this helps anyone stuck with AAC to get their hardware working for them while we wait for the package to eventually make it through the NEW queue. Discuss on Hacker News
  1. Such as, for example, any Apple AirPods, which only support AAC AFAICT.
  2. Which, as of Debian 12 is GNOME 3 under Wayland with PipeWire.
  3. I m not a lawyer, I don t know what kinds of infringement might or might not be possible here, do your own research, etc. 2 3 4
  4. And if you DO have a key setup with debsign you almost certainly don t need these instructions.
  5. This was originally phrased as explicitly does not grant any patent rights. It was pointed out on Hacker News that this is not exactly what it says, as it also includes a specific note that you ll need to acquire your own patent license. I ve now quoted the relevant section of the license for clarity.
  6. Wikipedia claims the base patents expire in 2031, with the extensions expiring in 2038, but its source for these claims is some guy s spreadsheet in a forum. The same discussion also brings up Wikipedia s claim and casts some doubt on it, so I m not entirely sure what s correct here, but I didn t feel like doing a patent deep-dive today. If someone can provide a clear answer that would be much appreciated.
  7. According to Jeremy B cha: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1021370#17

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)

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18 February 2024

Iustin Pop: New skis , new fun!

As I wrote a bit back, I had a really, really bad fourth quarter in 2023. As new years approached, and we were getting ready to go on a ski trip, I wasn t even sure if and how much I ll be able to ski. And I felt so out of it that I didn t even buy a ski pass for the whole week, just bought one day to see if a) I still like, and b) my knee can deal with it. And, of course, it was good. It was good enough that I ended up skiing the entire week, and my knee got better during the week. WTH?! I don t understand this anymore, but it was good. Good enough that this early year trip put me back on track and I started doing sports again. But the main point is, that during this ski week, and talking to the teacher, I realised that my ski equipment is getting a bit old. I bought everything roughly ten years ago, and while they still hold up OK, my ski skills have improved since then. I said to myself, 10 years is a good run, I ll replace this year the skis, next year the boot & helmet, etc. I didn t expect much from new skis - I mean, yes, better skis, but what does better mean? Well, once I ve read enough forum posts, apparently the skis I selected are that good , which to me meant they re not bad. Oh my, how wrong I was! Double, triple wrong! Rather than fighting with the skis, it s enough to think what I wand to do, and the skis do it. I felt OK-ish, maybe 10% limited by my previous skis, but the new skis are really good and also I know that I m just at 30% or so of the new skis - so room to grow. For now, I am able to ski faster, longer, and I feel less tired than before. I ve actually compared and I can do twice the distance in a day and feel slightly less tired at the end. I ve moved from this black is cool but a bit difficult, I ll do another run later in the day when I ve recovered to how cool, this blacks is quite empty of people, let s stay here for 2-3 more rounds . The skis are new, and I haven t used them on all the places I m familiar with - but the upgrade is huge. The people on the ski forum were actually not exaggerating, I realise now. St ckli++, and they re also made in Switzerland. Can t wait to get back to Saas Fee and to the couple of slopes that were killing me before, to see how they feel now. So, very happy with this choice. I d be even happier if my legs were less damaged, but well, you can t win them all. And not last, the skis are also very cool looking

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 :) ]


Emanuele Rocca: Enabling Kernel Settings in Debian

This time it s about enabling new kernel config options in the official Debian kernel packages. A few dependencies are needed to run the various scripts used by the Debian kernel folks, as well as to build the kernel itself: 
apt install git gpg python3-debian python3-dacite
apt build-dep linux
With that in place, fetch the linux and kernel-team repos: 
git clone --depth 1 https://salsa.debian.org/kernel-team/linux
git clone --depth 1 https://salsa.debian.org/kernel-team/kernel-team
So far you ve only got the Debian-specific bits. Fetch the actual kernel sources now. In the likely case that you re building a stable kernel, run the following from within the linux directory: 
debian/bin/genorig.py https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git
Use the torvalds repo if you re building an RC version instead: 
debian/bin/genorig.py https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Now generate the upstream tarball as well as debian/control. The first command will take a bit, and the second command will fail: but that s success just as the output says. 
debian/rules orig
debian/rules debian/control
Now generate patched sources with: 
debian/rules source
Time to edit the Kconfig and enable/disable whatever setting you wanted to change. Take a look around the files under debian/config/ to see where your changes should go. If it s a setting shared among multiple architectures that may be debian/config/config. For x86-specific things, the file is debian/config/amd64/config. On aarch64 debian/config/arm64/config. If in doubt, you could try asking #debian-kernel on IRC.
It may look like you need to figure out where exactly in the file the setting should be placed. That is not the case. There s a helpful script fixing things up for you: 
../kernel-team/utils/kconfigeditor2/process.py .
The above will fail if you forgot to run debian/rules source. The debian/build/source_rt/Kconfig file is needed by the script: 
Traceback (most recent call last):
  File "/tmp/linux/../kernel-team/utils/kconfigeditor2/process.py", line 19, in __init__
    menu = fs_menu[featureset or 'none']
           ~~~~~~~^^^^^^^^^^^^^^^^^^^^^^
KeyError: 'rt'
During handling of the above exception, another exception occurred:
[...]
FileNotFoundError: [Errno 2] No such file or directory: './debian/build/source_rt/Kconfig'
If that happens, run: 
debian/rules source
Now process.py should work fine and fix your config file.
Excellent, now the config is updated and we re ready to build the kernel. Off we go: 
export MAKEFLAGS=-j$(nproc)
export DEB_BUILD_PROFILES='pkg.linux.nokerneldbg pkg.linux.nokerneldbginfo pkg.linux.notools nodoc'
dpkg-buildpackage -b -nc -uc

10 February 2024

Andrew Cater: Debian point releases - updated media for Bullseye (11.9) and Bookworm (12.5) - 2024-02-10

It's been a LONG day: two point releases in a day takes of the order of twelve or thirteen hours of fairly solid work on behalf of those doing the releases and testing.Thanks firstly to the main Debian release team for all the initial work.Thanks to Isy, RattusRattus, Sledge and egw in Cottenham, smcv and Helen closer to the centre of Cambridge, cacin and others who have dropped in and out of IRC and helped testing.

I've been at home but active on IRC - missing the team (and the food) and drinking far too much coffee/eating too many biscuits.

We've found relatively few bugs that we haven't previously noted: it's been a good day. Back again, at some point a couple of months from now to do this all over again.With luck, I can embed a picture of the Cottenham folk below: it's fun to know _exactly_ where people are because you've been there yourself.



8 February 2024

Dirk Eddelbuettel: RcppArmadillo 0.12.8.0.0 on CRAN: New Upstream, Interface Polish

armadillo image Armadillo is a powerful and expressive C++ template library for linear algebra and scientific computing. It aims towards a good balance between speed and ease of use, has a syntax deliberately close to Matlab, and is useful for algorithm development directly in C++, or quick conversion of research code into production environments. RcppArmadillo integrates this library with the R environment and language and is widely used by (currently) 1119 other packages on CRAN, downloaded 32.5 million times (per the partial logs from the cloud mirrors of CRAN), and the CSDA paper (preprint / vignette) by Conrad and myself has been cited 575 times according to Google Scholar. This release brings a new (stable) upstream (minor) release Armadillo 12.8.0 prepared by Conrad two days ago. We, as usual, prepared a release candidate which we tested against the over 1100 CRAN packages using RcppArmadillo. This found no issues, which was confirmed by CRAN once we uploaded and so it arrived as a new release today in a fully automated fashion. We also made a small change that had been prepared by GitHub issue #400: a few internal header files that were cluttering the top-level of the include directory have been moved to internal directories. The standard header is of course unaffected, and the set of full / light / lighter / lightest headers (matching we did a while back in Rcpp) also continue to work as one expects. This change was also tested in a full reverse-dependency check in January but had not been released to CRAN yet. The set of changes since the last CRAN release follows.

Changes in RcppArmadillo version 0.12.8.0.0 (2024-02-06)
  • Upgraded to Armadillo release 12.8.0 (Cortisol Injector)
    • Faster detection of symmetric expressions by pinv() and rank()
    • Expanded shift() to handle sparse matrices
    • Expanded conv_to for more flexible conversions between sparse and dense matrices
    • Added cbrt()
    • More compact representation of integers when saving matrices in CSV format
  • Five non-user facing top-level include files have been removed (#432 closing #400 and building on #395 and #396)

Courtesy of my CRANberries, there is a diffstat report relative to previous release. More detailed information is on the RcppArmadillo page. Questions, comments etc should go to the rcpp-devel mailing list off the Rcpp R-Forge page. If you like this or other open-source work I do, you can sponsor me at GitHub.

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

7 February 2024

Reproducible Builds: Reproducible Builds in January 2024

Welcome to the January 2024 report from the Reproducible Builds project. In these reports we outline the most important things that we have been up to over the past month. If you are interested in contributing to the project, please visit our Contribute page on our website.

How we executed a critical supply chain attack on PyTorch John Stawinski and Adnan Khan published a lengthy blog post detailing how they executed a supply-chain attack against PyTorch, a popular machine learning platform used by titans like Google, Meta, Boeing, and Lockheed Martin :
Our exploit path resulted in the ability to upload malicious PyTorch releases to GitHub, upload releases to [Amazon Web Services], potentially add code to the main repository branch, backdoor PyTorch dependencies the list goes on. In short, it was bad. Quite bad.
The attack pivoted on PyTorch s use of self-hosted runners as well as submitting a pull request to address a trivial typo in the project s README file to gain access to repository secrets and API keys that could subsequently be used for malicious purposes.

New Arch Linux forensic filesystem tool On our mailing list this month, long-time Reproducible Builds developer kpcyrd announced a new tool designed to forensically analyse Arch Linux filesystem images. Called archlinux-userland-fs-cmp, the tool is supposed to be used from a rescue image (any Linux) with an Arch install mounted to, [for example], /mnt. Crucially, however, at no point is any file from the mounted filesystem eval d or otherwise executed. Parsers are written in a memory safe language. More information about the tool can be found on their announcement message, as well as on the tool s homepage. A GIF of the tool in action is also available.

Issues with our SOURCE_DATE_EPOCH code? Chris Lamb started a thread on our mailing list summarising some potential problems with the source code snippet the Reproducible Builds project has been using to parse the SOURCE_DATE_EPOCH environment variable:
I m not 100% sure who originally wrote this code, but it was probably sometime in the ~2015 era, and it must be in a huge number of codebases by now. Anyway, Alejandro Colomar was working on the shadow security tool and pinged me regarding some potential issues with the code. You can see this conversation here.
Chris ends his message with a request that those with intimate or low-level knowledge of time_t, C types, overflows and the various parsing libraries in the C standard library (etc.) contribute with further info.

Distribution updates In Debian this month, Roland Clobus posted another detailed 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) . Additionally 7 of the 8 bookworm images from the official download link build reproducibly at any later time. In addition to this, three reviews of Debian packages were added, 17 were updated and 15 were removed this month adding to our knowledge about identified issues. Elsewhere, Bernhard posted another monthly update for his work elsewhere in openSUSE.

Community updates There were made a number of improvements to our website, including Bernhard M. Wiedemann fixing a number of typos of the term nondeterministic . [ ] and Jan Zerebecki adding a substantial and highly welcome section to our page about SOURCE_DATE_EPOCH to document its interaction with distribution rebuilds. [ ].
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 254 and 255 to Debian but focusing on triaging and/or merging code from other contributors. This included adding support for comparing eXtensible ARchive (.XAR/.PKG) files courtesy of Seth Michael Larson [ ][ ], as well considerable work from Vekhir in order to fix compatibility between various and subtle incompatible versions of the progressbar libraries in Python [ ][ ][ ][ ]. Thanks!

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 January, a number of changes were made by Holger Levsen:
  • Debian-related changes:
    • Reduce the number of arm64 architecture workers from 24 to 16. [ ]
    • Use diffoscope from the Debian release being tested again. [ ]
    • Improve the handling when killing unwanted processes [ ][ ][ ] and be more verbose about it, too [ ].
    • Don t mark a job as failed if process marked as to-be-killed is already gone. [ ]
    • Display the architecture of builds that have been running for more than 48 hours. [ ]
    • Reboot arm64 nodes when they hit an OOM (out of memory) state. [ ]
  • Package rescheduling changes:
    • Reduce IRC notifications to 1 when rescheduling due to package status changes. [ ]
    • Correctly set SUDO_USER when rescheduling packages. [ ]
    • Automatically reschedule packages regressing to FTBFS (build failure) or FTBR (build success, but unreproducible). [ ]
  • OpenWrt-related changes:
    • Install the python3-dev and python3-pyelftools packages as they are now needed for the sunxi target. [ ][ ]
    • Also install the libpam0g-dev which is needed by some OpenWrt hardware targets. [ ]
  • Misc:
    • As it s January, set the real_year variable to 2024 [ ] and bump various copyright years as well [ ].
    • Fix a large (!) number of spelling mistakes in various scripts. [ ][ ][ ]
    • Prevent Squid and Systemd processes from being killed by the kernel s OOM killer. [ ]
    • Install the iptables tool everywhere, else our custom rc.local script fails. [ ]
    • Cleanup the /srv/workspace/pbuilder directory on boot. [ ]
    • Automatically restart Squid if it fails. [ ]
    • Limit the execution of chroot-installation jobs to a maximum of 4 concurrent runs. [ ][ ]
Significant amounts of node maintenance was performed by Holger Levsen (eg. [ ][ ][ ][ ][ ][ ][ ] etc.) and Vagrant Cascadian (eg. [ ][ ][ ][ ][ ][ ][ ][ ]). Indeed, Vagrant Cascadian handled an extended power outage for the network running the Debian armhf architecture test infrastructure. This provided the incentive to replace the UPS batteries and consolidate infrastructure to reduce future UPS load. [ ] Elsewhere in our infrastructure, however, Holger Levsen also adjusted the email configuration for @reproducible-builds.org to deal with a new SMTP email attack. [ ]

Upstream patches The Reproducible Builds project tries to detects, dissects and 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: Separate to this, Vagrant Cascadian followed up with the relevant maintainers when reproducibility fixes were not included in newly-uploaded versions of the mm-common package in Debian this was quickly fixed, however. [ ]
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:

2 February 2024

Ian Jackson: UPS, the Useless Parcel Service; VAT and fees

I recently had the most astonishingly bad experience with UPS, the courier company. They severely damaged my parcels, and were very bad about UK import VAT, ultimately ending up harassing me on autopilot. The only thing that got their attention was my draft Particulars of Claim for intended legal action. Surprisingly, I got them to admit in writing that the disbursement fee they charge recipients alongside the actual VAT, is just something they made up with no legal basis. What happened Autumn last year I ordered some furniture from a company in Germany. This was to be shipped by them to me by courier. The supplier chose UPS. UPS misrouted one of the three parcels to Denmark. When everything arrived, it had been sat on by elephants. The supplier had to replace most of it, with considerable inconvenience and delay to me, and of course a loss to the supplier. But this post isn t mostly about that. This post is about VAT. You see, import VAT was due, because of fucking Brexit. UPS made a complete hash of collecting that VAT. Their computers can t issue coherent documents, their email helpdesk is completely useless, and their automated debt collection systems run along uninfluenced by any external input. The crazy, including legal threats and escalating late payment fees, continued even after I paid the VAT discrepancy (which I did despite them not yet having provided any coherent calculation for it). This kind of behaviour is a very small and mild version of the kind of things British Gas did to Lisa Ferguson, who eventually won substantial damages for harassment, plus 10K of costs. Having tried asking nicely, and sending stiff letters, I too threatened litigation. I would have actually started a court claim, but it would have included a claim under the Protection from Harassment Act. Those have to be filed under the Part 8 procedure , which involves sending all of the written evidence you re going to use along with the claim form. Collating all that would be a good deal of work, especially since UPS and ControlAccount didn t engage with me at all, so I had no idea which things they might actually dispute. So I decided that before issuing proceedings, I d send them a copy of my draft Particulars of Claim, along with an offer to settle if they would pay me a modest sum and stop being evil robots at me. Rather than me typing the whole tale in again, you can read the full gory details in the PDF of my draft Particulars of Claim. (I ve redacted the reference numbers). Outcome The draft Particulars finally got their attention. UPS sent me an offer: they agreed to pay me 50, in full and final settlement. That was close enough to my offer that I accepted it. I mostly wanted them to stop, and they do seem to have done so. And I ve received the 50. VAT calculation They also finally included an actual explanation of the VAT calculation. It s absurd, but it s not UPS s absurd:
The clearance was entered initially with estimated import charges of 400.03, consisting of 387.83 VAT, and 12.20 disbursement fee. This original entry regrettably did not include the freight cost for calculating the VAT, and as such when submitted for final entry the VAT value was adjusted to include this and an amended invoice was issued for an additional 39.84. HMRC calculate the amount against which VAT is raised using the value of goods, insurance and freight, however they also may apply a VAT adjustment figure. The VAT Adjustment is based on many factors (Incidental costs in regards to a shipment), which includes charge for currency conversion if the invoice does not list values in Sterling, but the main is due to the inland freight from airport of destination to the final delivery point, as this charge varies, for example, from EMA to Edinburgh would be 150, from EMA to Derby would be 1, so each year UPS must supply HMRC with all values incurred for entry build up and they give an average which UPS have to use on the entry build up as the VAT Adjustment. The correct calculation for the import charges is therefore as follows: Goods value divided by exchange rate 2,489.53 EUR / 1.1683 = 2,130.89 GBP Duty: Goods value plus freight (%) 2,130.89 GBP + 5% = 2,237.43 GBP. That total times the duty rate. X 0 % = 0 GBP VAT: Goods value plus freight (100%) 2,130.89 GBP + 0 = 2,130.89 GBP That total plus duty and VAT adjustment 2,130.89 GBP + 0 GBP + 7.49 GBP = 2,348.08 GBP. That total times 20% VAT = 427.67 GBP As detailed above we must confirm that the final VAT charges applied to the shipment were correct, and that no refund of this is therefore due.
This looks very like HMRC-originated nonsense. If only they had put it on the original bills! It s completely ridiculous that it took four months and near-litigation to obtain it. Disbursement fee One more thing. UPS billed me a 12 disbursement fee . When you import something, there s often tax to pay. The courier company pays that to the government, and the consignee pays it to the courier. Usually the courier demands it before final delivery, since otherwise they end up having to chase it as a debt. It is common for parcel companies to add a random fee of their own. As I note in my Particulars, there isn t any legal basis for this. In my own offer of settlement I proposed that UPS should:
State under what principle of English law (such as, what enactment or principle of Common Law), you levy the disbursement fee (or refund it).
To my surprise they actually responded to this in their own settlement letter. (They didn t, for example, mention the harassment at all.) They said (emphasis mine):
A disbursement fee is a fee for amounts paid or processed on behalf of a client. It is an established category of charge used by legal firms, amongst other companies, for billing of various ancillary costs which may be incurred in completion of service. Disbursement fees are not covered by a specific law, nor are they legally prohibited. Regarding UPS disbursement fee this is an administrative charge levied for the use of UPS deferment account to prepay import charges for clearance through CDS. This charge would therefore be billed to the party that is responsible for the import charges, normally the consignee or receiver of the shipment in question. The disbursement fee as applied is legitimate, and as you have stated is a commonly used and recognised charge throughout the courier industry, and I can confirm that this was charged correctly in this instance.
On UPS s analysis, they can just make up whatever fee they like. That is clearly not right (and I don t even need to refer to consumer protection law, which would also make it obviously unlawful). And, that everyone does it doesn t make it lawful. There are so many things that are ubiquitous but unlawful, especially nowadays when much of the legal system - especially consumer protection regulators - has been underfunded to beyond the point of collapse. Next time this comes up I might have a go at getting the fee back. (Obviously I ll have to pay it first, to get my parcel.) ParcelForce and Royal Mail I think this analysis doesn t apply to ParcelForce and (probably) Royal Mail. I looked into this in 2009, and I found that Parcelforce had been given the ability to write their own private laws: Schemes made under section 89 of the Postal Services Act 2000. This is obviously ridiculous but I think it was the law in 2009. I doubt the intervening governments have fixed it. Furniture Oh, yes, the actual furniture. The replacements arrived intact and are great :-).

comment count unavailable comments

31 January 2024

Valhalla's Things: Macrame Bookbag

Posted on January 31, 2024
Tags: madeof:atoms, craft:macrame
a macrame bag in ~3 mm ecru yarn, with very irregular knots of different types, holding a book with a blue cover. The bottom part has a rigid single layer triangle and a fringe. In late 2022 I prepared a batch of drawstring backpacks in cotton as reusable wrappers for Christmas gifts; however I didn t know what cord to use, didn t want to use paracord, and couldn t find anything that looked right in the local shops. With Christmas getting dangerously closer, I visited a craft materials website for unrelated reasons, found out that they sold macrame cords, and panic-bought a few types in the hope that at least one would work for the backpacks. I got lucky, and my first choice fitted just fine, and I was able to finish the backpacks in time for the holidays. And then I had a box full of macrame cords in various sizes and types that weren t the best match for the drawstring in a backpack, and no real use for them. I don t think I had ever done macrame, but I have made friendship bracelets in primary school, and a few Friendship Bracelets, But For Real Men So We Call Them Survival Bracelets(TM) more recently, so I didn t bother reading instructions or tutorials online, I just grabbed the Ashley Book of Knots to refresh myself on the knots used, and decided to make myself a small bag for an A6 book. I choose one of the thin, ~3 mm cords, Tre Sfere Macram Barbante, of which there was plenty, so that I could stumble around with no real plan. A loop of four cords, with a handle made of square knots that keeps it together. I started by looping 5 m of cord, making iirc 2 rounds of a loop about the right size to go around the book with a bit of ease, then used the ends as filler cords for a handle, wrapped them around the loop and worked square knots all over them to make a handle. Then I cut the rest of the cord into 40 pieces, each 4 m long, because I had no idea how much I was going to need (spoiler: I successfully got it wrong :D ) I joined the cords to the handle with lark head knots, 20 per side, and then I started knotting without a plan or anything, alternating between hitches and square knots, sometimes close together and sometimes leaving some free cord between them. And apparently I also completely forgot to take in-progress pictures. I kept working on this for a few months, knotting a row or two now and then, until the bag was long enough for the book, then I closed the bottom by taking one cord from the front and the corresponding on the back, knotting them together (I don t remember how) and finally I made a rigid triangle of tight square knots with all of the cords, progressively leaving out a cord from each side, and cutting it in a fringe. I then measured the remaining cords, and saw that the shortest ones were about a meter long, but the longest ones were up to 3 meters, I could have cut them much shorter at the beginning (and maybe added a couple more cords). The leftovers will be used, in some way. And then I postponed taking pictures of the finished object for a few months. The same bag, empty and showing how the sides aren't straight. Now the result is functional, but I have to admit it is somewhat ugly: not as much for the lack of a pattern (that I think came out quite fine) but because of how irregular the knots are; I m not confident that the next time I will be happy with their regularity, either, but I hope I will improve, and that s one important thing. And the other important thing is: I enjoyed making this, even if I kept interrupting the work, and I think that there may be some other macrame in my future.

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

Russell Coker: Thinkpad X1 Yoga Gen3

I just bought myself a Thinkpad X1 Yoga Gen3 for $359.10. I have been quite happy with the Thinkpad X1 Carbon Gen5 I ve had for just over a year (apart from my mistake in buying one with lost password) [1] and I normally try to get more use out of a computer than that. If I divide total cost by the time that I ve had it working that comes out to about $1.30 per day. I would pay more than that for a laptop and I have paid much more than that for laptops in the past, but I prefer not to. I was initially tempted to buy a new Thinkpad by the prices of high end X1 devices dropping, this new Yoga has 16G of RAM and a 2560*1440 screen that s a good upgrade from 8G with 1920*1080. The CPU of my new Thinkpad is a quad core i5-8350U that rates 6226 [2] and is a decent upgrade from the dual core i5-6300U that rates 3239 [3] although that wasn t a factor as I found the old CPU fast enough. The Yoga Gen3 has a minimum weight of 1.4Kg and mine might not be the lightest model in the range while the old Carbon weighs 1.14Kg. I can really feel the difference. It s also slightly larger but fortunately still fits in the pocket of my Scottware jacket. The higher resolution screen and more RAM were not sufficient to make me want to spend some money. The deciding factor is that as I m working on phones with touch screens it is a benefit to use a laptop with a touch screen so I can do more testing. The Yoga I bought was going cheap because the touch part of the touch screen is broken but the stylus still works, this is apparently a common failure mode of the Yoga. The Yoga has a brighter screen than the Carbon and seems to have better contrast. I think Lenovo had some newer technology for that generation of laptops or maybe my Carbon is slightly defective in that regard. It s a hazard of buying second hand that if something basically works but isn t quite as good as it should be then you will never know. I m happy with this purchase and I recommend that everyone who buys laptops secondhand the way I do only get 1440p or better displays. I ve currently got the Kitty terminal emulator [4] setup with 9 windows that each have 103 or 104 columns and 26 or 28 rows of text. That s a lot of terminals on a laptop screen!
Related posts:
  1. Thinkpad X1 Carbon Gen5 Gen1 Since February 2018 I have been using a Thinkpad...
  2. USB-PD and GaN A recent development is cheap Gallium Nitride based power...
  3. More About the Thinkpad X301 Last month I blogged about the Thinkpad X301 I got...

28 January 2024

Niels Thykier: Annotating the Debian packaging directory

In my previous blog post Providing online reference documentation for debputy, I made a point about how debhelper documentation was suboptimal on account of being static rather than online. The thing is that debhelper is not alone in this problem space, even if it is a major contributor to the number of packaging files you have to to know about. If we look at the "competition" here such as Fedora and Arch Linux, they tend to only have one packaging file. While most Debian people will tell you a long list of cons about having one packaging file (such a Fedora's spec file being 3+ domain specific languages "mashed" into one file), one major advantage is that there is only "the one packaging file". You only need to remember where to find the documentation for one file, which is great when you are running on wetware with limited storage capacity. Which means as a newbie, you can dedicate less mental resources to tracking multiple files and how they interact and more effort understanding the "one file" at hand. I started by asking myself how can we in Debian make the packaging stack more accessible to newcomers? Spoiler alert, I dug myself into rabbit hole and ended up somewhere else than where I thought I was going. I started by wanting to scan the debian directory and annotate all files that I could with documentation links. The logic was that if debputy could do that for you, then you could spend more mental effort elsewhere. So I combined debputy's packager provided files detection with a static list of files and I quickly had a good starting point for debputy-based packages.
Adding (non-static) dpkg and debhelper files to the mix Now, I could have closed the topic here and said "Look, I did debputy files plus couple of super common files". But I decided to take it a bit further. I added support for handling some dpkg files like packager provided files (such as debian/substvars and debian/symbols). But even then, we all know that debhelper is the big hurdle and a major part of the omission... In another previous blog post (A new Debian package helper: debputy), I made a point about how debputy could list all auxiliary files while debhelper could not. This was exactly the kind of feature that I would need for this feature, if this feature was to cover debhelper. Now, I also remarked in that blog post that I was not willing to maintain such a list. Also, I may have ranted about static documentation being unhelpful for debhelper as it excludes third-party provided tooling. Fortunately, a recent update to dh_assistant had provided some basic plumbing for loading dh sequences. This meant that getting a list of all relevant commands for a source package was a lot easier than it used to be. Once you have a list of commands, it would be possible to check all of them for dh's NOOP PROMISE hints. In these hints, a command can assert it does nothing if a given pkgfile is not present. This lead to the new dh_assistant list-guessed-dh-config-files command that will list all declared pkgfiles and which helpers listed them. With this combined feature set in place, debputy could call dh_assistant to get a list of pkgfiles, pretend they were packager provided files and annotate those along with manpage for the relevant debhelper command. The exciting thing about letting debpputy resolve the pkgfiles is that debputy will resolve "named" files automatically (debhelper tools will only do so when --name is passed), so it is much more likely to detect named pkgfiles correctly too. Side note: I am going to ignore the elephant in the room for now, which is dh_installsystemd and its package@.service files and the wide-spread use of debian/foo.service where there is no package called foo. For the latter case, the "proper" name would be debian/pkg.foo.service. With the new dh_assistant feature done and added to debputy, debputy could now detect the ubiquitous debian/install file. Excellent. But less great was that the very common debian/docs file was not. Turns out that dh_installdocs cannot be skipped by dh, so it cannot have NOOP PROMISE hints. Meh... Well, dh_assistant could learn about a new INTROSPECTABLE marker in addition to the NOOP PROMISE and then I could sprinkle that into a few commands. Indeed that worked and meant that debian/postinst (etc.) are now also detectable. At this point, debputy would be able to identify a wide range of debhelper related configuration files in debian/ and at least associate each of them with one or more commands. Nice, surely, this would be a good place to stop, right...?
Adding more metadata to the files The debhelper detected files only had a command name and manpage URI to that command. It would be nice if we could contextualize this a bit more. Like is this file installed into the package as is like debian/pam or is it a file list to be processed like debian/install. To make this distinction, I could add the most common debhelper file types to my static list and then merge the result together. Except, I do not want to maintain a full list in debputy. Fortunately, debputy has a quite extensible plugin infrastructure, so added a new plugin feature to provide this kind of detail and now I can outsource the problem! I split my definitions into two and placed the generic ones in the debputy-documentation plugin and moved the debhelper related ones to debhelper-documentation. Additionally, third-party dh addons could provide their own debputy plugin to add context to their configuration files. So, this gave birth file categories and configuration features, which described each file on different fronts. As an example, debian/gbp.conf could be tagged as a maint-config to signal that it is not directly related to the package build but more of a tool or style preference file. On the other hand, debian/install and debian/debputy.manifest would both be tagged as a pkg-helper-config. Files like debian/pam were tagged as ppf-file for packager provided file and so on. I mentioned configuration features above and those were added because, I have had a beef with debhelper's "standard" configuration file format as read by filearray and filedoublearray. They are often considered simple to understand, but it is hard to know how a tool will actually read the file. As an example, consider the following:
  • Will the debhelper use filearray, filedoublearray or none of them to read the file? This topic has about 2 bits of entropy.
  • Will the config file be executed if it is marked executable assuming you are using the right compat level? If it is executable, does dh-exec allow renaming for this file? This topic adds 1 or 2 bit of entropy depending on the context.
  • Will the config file be subject to glob expansions? This topic sounds like a boolean but is a complicated mess. The globs can be handled either by debhelper as it parses the file for you. In this case, the globs are applied to every token. However, this is not what dh_install does. Here the last token on each line is supposed to be a directory and therefore not subject to globs. Therefore, dh_install does the globbing itself afterwards but only on part of the tokens. So that is about 2 bits of entropy more. Actually, it gets worse...
    • If the file is executed, debhelper will refuse to expand globs in the output of the command, which was a deliberate design choice by the original debhelper maintainer took when he introduced the feature in debhelper/8.9.12. Except, dh_install feature interacts with the design choice and does enable glob expansion in the tool output, because it does so manually after its filedoublearray call.
So these "simple" files have way too many combinations of how they can be interpreted. I figured it would be helpful if debputy could highlight these difference, so I added support for those as well. Accordingly, debian/install is tagged with multiple tags including dh-executable-config and dh-glob-after-execute. Then, I added a datatable of these tags, so it would be easy for people to look up what they meant. Ok, this seems like a closed deal, right...?
Context, context, context However, the dh-executable-config tag among other are only applicable in compat 9 or later. It does not seem newbie friendly if you are told that this feature exist, but then have to read in the extended description that that it actually does not apply to your package. This problem seems fixable. Thanks to dh_assistant, it is easy to figure out which compat level the package is using. Then tweak some metadata to enable per compat level rules. With that tags like dh-executable-config only appears for packages using compat 9 or later. Also, debputy should be able to tell you where packager provided files like debian/pam are installed. We already have the logic for packager provided files that debputy supports and I am already using debputy engine for detecting the files. If only the plugin provided metadata gave me the install pattern, debputy would be able tell you where this file goes in the package. Indeed, a bit of tweaking later and setting install-pattern to usr/lib/pam.d/ name , debputy presented me with the correct install-path with the package name placing the name placeholder. Now, I have been using debian/pam as an example, because debian/pam is installed into usr/lib/pam.d in compat 14. But in earlier compat levels, it was installed into etc/pam.d. Well, I already had an infrastructure for doing compat file tags. Off we go to add install-pattern to the complat level infrastructure and now changing the compat level would change the path. Great. (Bug warning: The value is off-by-one in the current version of debhelper. This is fixed in git) Also, while we are in this install-pattern business, a number of debhelper config files causes files to be installed into a fixed directory. Like debian/docs which causes file to be installed into /usr/share/docs/ package . Surely, we can expand that as well and provide that bit of context too... and done. (Bug warning: The code currently does not account for the main documentation package context) It is rather common pattern for people to do debian/foo.in files, because they want to custom generation of debian/foo. Which means if you have debian/foo you get "Oh, let me tell you about debian/foo ". Then you rename it to debian/foo.in and the result is "debian/foo.in is a total mystery to me!". That is suboptimal, so lets detect those as well as if they were the original file but add a tag saying that they are a generate template and which file we suspect it generates. Finally, if you use debputy, almost all of the standard debhelper commands are removed from the sequence, since debputy replaces them. It would be weird if these commands still contributed configuration files when they are not actually going to be invoked. This mostly happened naturally due to the way the underlying dh_assistant command works. However, any file mentioned by the debhelper-documentation plugin would still appear unfortunately. So off I went to filter the list of known configuration files against which dh_ commands that dh_assistant thought would be used for this package.
Wrapping it up I was several layers into this and had to dig myself out. I have ended up with a lot of data and metadata. But it was quite difficult for me to arrange the output in a user friendly manner. However, all this data did seem like it would be useful any tool that wants to understand more about the package. So to get out of the rabbit hole, I for now wrapped all of this into JSON and now we have a debputy tool-support annotate-debian-directory command that might be useful for other tools. To try it out, you can try the following demo: In another day, I will figure out how to structure this output so it is useful for non-machine consumers. Suggestions are welcome. :)
Limitations of the approach As a closing remark, I should probably remind people that this feature relies heavily on declarative features. These include:
  • When determining which commands are relevant, using Build-Depends: dh-sequence-foo is much more reliable than configuring it via the Turing complete configuration we call debian/rules.
  • When debhelper commands use NOOP promise hints, dh_assistant can "see" the config files listed those hints, meaning the file will at least be detected. For new introspectable hint and the debputy plugin, it is probably better to wait until the dust settles a bit before adding any of those.
You can help yourself and others to better results by using the declarative way rather than using debian/rules, which is the bane of all introspection!

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

Dirk Eddelbuettel: qlcal 0.0.10 on CRAN: Calendar Updates

The tenth release of the qlcal package arrivied at CRAN today. qlcal delivers the calendaring parts of QuantLib. It is provided (for the R package) as a set of included files, so the package is self-contained and does not depend on an external QuantLib library (which can be demanding to build). qlcal covers over sixty country / market calendars and can compute holiday lists, its complement (i.e. business day lists) and much more. Examples are in the README at the repository, the package page, and course at the CRAN package page. This releases synchronizes qlcal with the QuantLib release 1.33 and its updates to 2024 calendars.

Changes in version 0.0.10 (2024-01-24)
  • Synchronized with QuantLib 1.33

Courtesy of my CRANberries, there is a diffstat report for this release. See the project page and package documentation for more details, and more examples. If you like this or other open-source work I do, you can now sponsor me at GitHub.

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

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