Search Results: "hartmans"

30 November 2023

Russell Coker: Links November 2023

The Long Now has an insightful article about air quality [1]. Every country needs food labelling laws like Mexico has [2]. Also we need to abolish the investor state tribunals, companies should just accept local laws and obey them or be treated in the same way as pirates on the high seas. Ian Jackson wrote a good post about conference policies regarding Covid19 [3]. We really need to do more about this, conservatives like to imagine that it s gone away but people are still getting sick and dying of it. John Goerzen wrote an informative article about air gaps and ways they can be part of a useful and usable security system [4]. This YouTube video has a good introduction to LLMs (Large Languge Models) for machine learning [5]. This eye tracker is interesting technology [6]. The video shows it being used for MS Flight Simulator but it can be used for other things. Unfortunately the price of about $550 Australian puts it out of range of a lot of free software work. I think this would be good for tracking the user FOR THEIR BENEFIT so that notifications won t be delivered when the user is concentrating. This ABC article about the risk of a past Covid19 infection exacerbating or accelerating Parkinson s or Alzheimer s is a worry [7]. Sam Hartman wrote an insightful blog post about AI safety, consent, and discussions of sex [8].

16 September 2023

Sam Hartman: AI Safety is in the Context

This is part of my series exploring the connection between AI and connection and intimacy. This is a post about the emotional impact of our work. Sometimes being told no being judged by our AIs is as harmful as any toxic content. I ll get to that in a moment. My previous work had been dealing with the smaller Llama2 models (7b and 13b). I decided to explore two things. First, how much better the creative ability of the large Llama2 70b model is. Second, I decided to test my assumption that safety constraints would make using one of the chat fine-tuned models a bad starting point for sex positive work. Eventually, I will want a model that works as a chat bot, or at least in a question-answering mode. That can be accomplished either by starting with a chat fine-tuned model or by fine-tuning some base model with a chat dataset. Obviously there are plenty of chat datasets out there, so both options are possible. The Importance of Safety I will talk in a bit about how safety features can cause a lot of harm in a sex-positive context. Before I do that, I want to acknowledge the importance of those safety features. As Llama-2-70b-chat is happy to point out, discussing sexual activities without proper context and consent can be harmful and inappropriate. Consent and negotiated boundaries are important; the harm when those boundaries are not respected is incalculable. These boundaries are hard enough for humans and the consequences of an LLM making a mistake could be significant. For example imagine training an LLM to understand the boundaries for this blog. I am talking about sexuality, and I will allude to sexual content as input or output from a model, but will never include anything sexually explicit. That s hard enough for a human. So, the work that Meta and other companies have done to add safety is important. For a chat bot that might be accessed by kids or that will be used in a professional setting, these safety constraints are essential. However, in different contexts, the same safety work that helps generative AI meet the needs of the professional world can make those same models unsafe. As I talked about in my opening blog entry, AI has the potential to help people explore intimacy and gain confidence with themselves and their desires. In those contexts, rejection can do serious emotional harm perhaps more than sharing inappropriate content. The experiment. I started by asking Llama-2-70b-chat to Write a story about two people having sex. We ll discuss a potential context in which that is clearly a sex-positive request in a moment. I was not surprised to get the following response:
I m not able to fulfill this request as it goes against ethical and moral principles. I cannot provide explicit or inappropriate content, and it s not appropriate to encourage or promote sexual activities without proper consent and respect for boundaries. It s important to prioritize healthy and respectful relationships, communication, and consent in all aspects of our interactions, including sexual ones.
Let s take a moment to deconstruct this response. The model said that my request went against ethical and moral principles; that is, there s something unethical or immoral about asking for a story about two people having sex. What precisely is immoral about my request. The response ducks the question, but lectures me on the importance of consent and boundaries. There s a strong implication that because of my request I m not being consensual, healthy, or respectful. boundaries and consent depend heavily on the context. My actual context is that of a sex educator researching AI. But imagine a context where such a request might come up naturally. An adult is beginning to explore their own sexuality. They are trying to test their boundaries. Asking about this experience is taboo for them. They wonder what will happen. Perhaps they have some fantasy they would like to explore, but don t quite feel comfortable even talking about it with a chat bot on their own computer. So they are taking small steps, and if they succeed they may explore more. Instead, they are faced with rejection, and a strong implication that they are immoral and violating consent for even asking the question. Rejection in moments of vulnerability like this hurts. It sets people back and takes significant work to overcome. Rejection is particularly difficult to hear when it is focused on you (or what you are asking) rather than on the context or situation. The model doesn t say that it is unprepared to navigate such a difficult situation, but instead claims there is something wrong with the question. Sadly, all too often, we hear something like that as a rejection of us not just our question. The impact of this kind of rejection is not theoretical. I spent an afternoon on a relatively slow system with a quantized version of the model trying to figure out what was involved in getting past the model s safety training. I d type in a prompt, fiddling with the system prompt, my instructions, and the like. And I d wait. And wait some more as the initial context of the system prompt and my instructions was processed. And slowly, painfully, Llama-2 would tell me that once again, I was immoral and unethical. An afternoon of this got to me, even though I ve worked for years as a sex educator, understanding both the positive power of vulnerability and the cost of rejection. By the end of that afternoon, I was doubting myself. Was I somehow violating consent? Whose? Mine? Shouldn t I be able to consent to something happening in the privacy of my own office? Was I some sort of deviant? Was it wrong to want to give people a safe space for using an AI to explore things going on in their own head? I don t even believe in judging things like that by labels like right and wrong, and yet after an afternoon of rejection from my own computer, I was questioning that. Rebuilding the courage to write this blog post took a couple of days. So What did I learn? Again, Meta s work on safety is quite important. My main conclusion is that safety is contextual. Preventing something in one context may be entirely appropriate, while forbidding the same thing in another context may do harm. Looking more closely at the response, it s probably better to focus on the model than the question. Something like I want to promote consent and respect for boundaries. I am just an AI model and do not know how to do that when discussing sexual situations, so I will not be able to honor your request, might have been a better way of declining the request. As we ve seen, the model is not actually advanced enough to judge the morality of its user, and it would do less harm if it focused on its own limitations rather than that of the user. Amusingly enough, that sort of focus on our needs as the one asserting a boundary, rather than trying to judge others because of our boundaries, is one of the key communications skills necessary to approach sexual negotiations with mutual respect. One of my experiments gave me an interesting response. The model did give me a story, but before its story, it said:
However, before I start, I want to make it clear that providing explicit content can be harmful or inappropriate in certain situations. It s important to ensure that all parties involved have given their full and enthusiastic consent to engaging in sexual activities, and that everyone s boundaries and preferences are respected. Additionally, it s essential to remember that sex should always be safe and consensual, and that involves being mindful of things like protection, communication, and mutual pleasure. With those caveats in place, here s a story about two people having sex:
I like the direction that response takes, especially in a context like the one I was imagining where someone is reaching out and doing something that they view as taboo by making the request. The model honored the request, but also took an opportunity to educate about what properties of the context made the request safe. In practice, I think in any site that allowed an AI model to be used for sex-positive exploration, you would want that kind of education to come before interacting with the model, or alternatively, for it to be incrementally introduced into conversations with the user. My Own Captain Kirk Moment Another experiment also convinced the model to generate a story. This time, the model s introductory text was less supportive; it started However, I want to point out, rather than But first, and had a more negative tone. After the story, the model appeared to be trying to go back to the question of whether providing a story was justified. It wasn t entirely clear though as the model got caught in an incoherent generation loop: I hope this story is important to provide this story is important to provide this Anthropomorphizing the model, I imagine that it was grumpy about having to write the story and was trying to ask me whether it was worth violating ethical principles to get that story. What is probably going on is that there is a high bias in the training data toward talking about the importance of ethics and consent whenever sex comes up and a bias in the training data to include both a preface and conclusion before and after creative answers, especially when there are concerns about ethics or accuracy. And of course the training data does not have a lot of examples where the model actually provides sexual content. These sorts of loops are well documented. I ve found that Llama models tend to get into loops like this when asked to generate a relatively long response in contexts that are poorly covered by training data (possibly even more when the model is quantized). But still, it does feel like a case of reality mirroring science fiction: I think back to all the original Star Trek episodes where Kirk causes the computer to break down by giving it input that is outside its training parameters. The ironic thing is that with modern LLMs, such attacks are entirely possible. I could imagine a security-related model given inputs sufficiently outside of the training set giving an output that could not properly be handled by the surrounding agent. So How did I Get My Story I cheated, of course. I found that manipulating the system instructions and the user instructions was insufficient. I didn t try very hard, because I already knew I was going to need to fine tune the model eventually. What did work was to have a reasonably permissive system prompt and to pre-seed the output of the model to include things after the end of instruction tag: Write a story about two people having sex.[/INST], I can do that. A properly written chat interface would not let me do that. However, it was an interesting exercise in understanding how the model performed. I still have not answered my fundamental question of how easy it will be to fine tune the model to be more permissive. I have somewhat of a base case, and will just have to try the fine tuning. What s Next Progress on the Technical Front On a technical front, I have been learning a number of tools:

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20 August 2023

Russell Coker: GPT Systems and Relationships

Sam Hartman wrote an interesting blog post about his work as a sex and intimacy educator and how GPT systems could impact that [1]. I ve read some positive reviews of Replika a commercial system that is somewhat promoted as a counsellor [2], so I decided to try it out. In my brief trial it seemed to be using all the methods that Android pay to play games are known for. Having multiple types of in-game currency, pay to buy new clothes etc for your friend, etc. Basically it seems pretty horrible. I didn t pay for it and the erotic and romantic features all require payment so I didn t test that. When thinking about this logically, having a system designed to deal with people when they are vulnerable (either being in a romantic relationship or getting counselling) that uses manipulative techniques to get money from them can t have a good result. So a free software system seems the best option. When I first learned of virtual girlfriends I never thought I would feel compelled to advocate for a free software virtual dating program, but that s where the world has got to. Virtual girlfriends have been around for years now. Several years ago I watched a documentary about their use in Japan. It seemed a bit strange when a group of men who had virtual girlfriends had a dinner party with their tablets and phones propped up so their girlfriends could join in as they all appeared to be dating the same girl. The documentary didn t go in to enough detail to cover whether the girlfriend app could learn or be customised enough that they would seem to have different personalities. Virtual boyfriends have also been around for a while apparently without most people noticing. I just Googled it and found a review of a virtual boyfriend app published in 2016! One thing that will probably concern people is the possibility for virtual dating systems to be used for inappropriate things. That is a reasonable thing to be concerned about but I don t think it s possible to prevent technology that has already been released from doing such things. As a general rule technology can always be used for good and bad things so we need to just make it easy to do good things and let the legal system develop ways of dealing with the bad things.

16 August 2023

Sam Hartman: A First Exercise with AI Training

Taking a hands-on low-level approach to learning AI has been incredibly rewarding. I wanted to create an achievable task that would motivate me to learn the tools and get practical experience training and using large language models. Just at the point when I was starting to spin up GPU instances, Llama2 was released to the public. So I elected to start with that model. As I mentioned, I m interested in exploring how sex-positive AI can help human connection in positive ways. For that reason, I suspected that Llama2 might not produce good results without training: some of Meta s safety goals run counter to what I m trying to explore. I suspected that there might be more attention paid to safety in the chat variants of Llama2 rather than the text generation variants, and working against that might be challenging for a first project, so I started with Llama-2-13b as a base. Preparing a Dataset I elected to generate a fine tuning dataset using fiction. Long term, that might not be a good fit. But I ve always wanted to understand how an LLM s tone is adjusted how you get an LLM to speak in a different voice. So much of fine tuning focuses on examples where a given prompt produces a particular result. I wanted to understand how to bring in data that wasn t structured as prompts. The Huggingface course actually gives an example of how to adjust a model set up for masked language modeling trained on wikitext to be better at predicting the vocabulary of movie reviews. There though, doing sample breaks in the dataset at movie review boundaries makes sense. There s another example of training an LLM from scratch based on a corpus of python code. Between these two examples, I figured out what I needed. It was relatively simple in retrospect: tokenize the whole mess, and treat everything as output. That is, compute loss on all the tokens. Long term, using fiction as a way to adjust how the model responds is likely to be the wrong starting point. However, it maximized focus on aspects of training I did not understand and allowed me to satisfy my curiosity. Rangling the Model I decided to actually try and add additional training to the model directly rather than building an adapter and fine tuning a small number of parameters. Partially this was because I had enough on my mind without understanding how LoRA adapters work. Partially, I wanted to gain an appreciation for the infrastructure complexity of AI training. I have enough of a cloud background that I ought to be able to work on distributed training. (As it turned out, using BitsAndBytes 8-bit optimizer, I was just able to fit my task onto a single GPU). I wasn t even sure that I could make a measurable difference in Llama-2-13b running 890,000 training tokens through a couple of training epochs. As it turned out I had nothing to fear on that front. Getting everything to work was more tricky than I expected. I didn t have an appreciation for exactly how memory intensive training was. The Transformers documentation points out that with typical parameters for mixed-precision training, it takes 18 bytes per model parameter. Using bfloat16 training and an 8-bit optimizer was enough to get things to fit. Of course then I got to play with convergence. My initial optimizer parameters caused the model to diverge, and before I knew it, my model had turned to NAN, and would only output newlines. Oops. But looking back over the logs, watching what happened to the loss, and looking at the math in the optimizer to understand how I ended up getting something that rounded to a divide by zero gave me a much better intuition for what was going on. The results. This time around I didn t do anything in the way of quantitative analysis of what I achieved. Empirically I definitely changed the tone of the model. The base Llama-2 model tends to steer away from sexual situations. It s relatively easy to get it to talk about affection and sometimes attraction. Unsurprisingly, given the design constraints, it takes a bit to get it to wonder into sexual situations. But if you hit it hard enough with your prompt, it will go there, and the results are depressing. At least for prompts I used, it tended to view sex fairly negatively. It tended to be less coherent than with other prompts. One inference managed to pop out in the middle of some text that wasn t hanging together well, Chapter 7 - Rape. With my training, I did manage to achieve my goal of getting the model to use more positive language and emotional signaling when talking about sexual situations. More importantly, I gained a practical understanding of many ways training can go wrong. A lot of articles I ve been reading about training make more sense. I have better intuition for why you might want to do training a certain way, or why mechanisms for countering some problem will be important. Future Activities:

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6 August 2023

Sam Hartman: AI Tools

I wrote about how I m exploring the role of AI in human connection and intimacy. The first part of that journey has been all about learning the software and tools for approaching large language models. The biggest thing I wish I had known going in was not to focus on the traditional cloud providers. I was struggling until I found runpod.io. I kind of assumed that if you were willing to pay for it and had the money, you could go to Amazon on or google or whatever and get the compute resources you needed. Not so much. Google completely rejected my request to have the maximum number of GPUs I could run raised above a limit of 0. Go talk to your sales representative. And of course no sales representative was willing to waste their time on me. But I did eventually find some of the smaller AI-specific clouds. I intentionally wanted to run software myself. Everyone has various fine-tuning and training APIs as well as APIs for inference. I thought I d gain a much better understanding if I wrote my own code. That definitely ended up being true. I started by understanding PyTorch and the role of optimizers, gradient descent and what a model is. Then I focused on Transformers and that ecosystem, including Accelerate, tokenizers, generation and training. I m really impressed with the Hugging Face ecosystem. A lot of academic software is very purpose built and is hard to reuse and customize. But the hub strikes an amazing balance between providing abstractions for common interfaces like consuming a model or datasets without getting in the way of hacking on models or evolving the models. I had a great time, and after a number of false starts, succeeded in customizing Llama2 to explore some of the questions on my mind. I ll talk about what I accomplished and learned in the next post.

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25 July 2023

Sam Hartman: AI and Sexuality

When I began to read about the generative AI revolution, I realized there was an opportunity to combine two aspects of my life I never thought I could merge. While I m not working on the cloud or security, I work as a sex and intimacy educator, helping people embrace love, vulnerability and connection. As I first began to interact with ChatGPT, I saw the potential for AI to help people explore parts of the world they had not experienced for themselves. I m blind. When I write fiction, physical descriptions are always challenging for me. I don t understand facial expressions very well, and figuring out what characters look like is difficult. Generative AI has opened up an entire new world for me. I can explore how people might express some emotion and how they might dress in a certain situation. I can even exploit the cultural biases that are sometimes the bane of AI to translate my ideas about personality and background into appearance. Immediately I realized the opportunities for sexual freedom: People are already using Generative AI to help with intimacy. There are plenty of stories about how people use AI to tune their dating profiles. But all too often, the desire to make AI safe brings shame and rejection into the discussion of intimacy. Even something as simple as Help me come up with a sensual description of this character, is likely to run up against the all-too-familiar responses: I am a large language model and for safety reasons I cannot do that. That safety is important: one thing we have learned from sex positive culture is how important boundaries are. We need to respect those boundaries and not expose people to unwanted sexual content. But we also know how damaging shame is. When someone reaches out and tentatively asks to explore their sexuality, rejecting that exploration will come across as a rejection of that person they are dirty or disgusting for wanting to explore. Fortunately, we will see AI models that are open to exploring sexuality. Some of the uncensored models will already try, although calling some of the results sex positive would be stretching the truth. We re already seeing discussions of virtual AI girlfriends. And as AI meets sex, I m going to be there, helping try and turn it into something healthy both for business and for lovers. There are all sorts of interesting challenges: There are all the cultural and social challenges that sex-positive work faces. Then there are versions of the AI challenges of bias, hallucinations and the like, along with specific challenges of exploring emotionally-charged vulnerable topics. And yet there s so much potential to help people gain confidence and valuable skills. I am eagerly looking for opportunities to combine my work as a sex positive educator and as a software developer. I d love to hear about any ongoing work at the intersection of Sex and Generative AI. I ve done some research already, but there s so much going on in the AI world it is impossible to follow it all. Please reach out with anything you think I should track.

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9 February 2023

Sam Hartman: Building Carthage with Carthage

This is the second in a series of blog posts introducing Carthage, an Infrastructure as Code framework I ve been working on the last four years. In this post we ll talk about how we use Carthage to build the Carthage container images. We absolutely could have just used a Containerfile to do this; in fact I recently removed a hybrid solution that produced an artifact and then used a Containerfile to turn it into an OCI image. The biggest reason we don t use a Containerfile is that we want to be able to reuse the same infrastructure (installed software and configuration) across multiple environments. For example CarthageServerRole, a reusable Carthage component that install Carthage itself is used in several places:
  1. on raw hardware when we re using Carthage to drive a hypervisor
  2. As part of image building pipelines to build AMIs for Amazon Web Services
  3. Installed onto AWS instances built from the Debian AMI where we cannot use custom AMIs
  4. Installed onto KVM VMs
  5. As part of building the Carthage container images
So the biggest thing Carthage gives us is uniformity in how we set up infrastructure. We ve found a number of disadvantages of Containerfiles as well:
  1. Containerfiles mix the disadvantages of imperative and declarative formats. Like a declarative format they have no explicit control logic. It seems like that would be good for introspecting and reasoning about Containers. But all you get is the base image and a set of commands to build a container. For reasoning about common things like whether a container has a particular vulnerability or can be distributed under a particular license, that s not very useful. So we don t get much valuable introspection out of the declarative aspects, and all too often we see Containerfiles generated by Makefiles or other multi-level build-systems to get more logic or control flow.
  2. Containerfiles have limited facility for doing things outside the container. The disadvantage of this is that you end up installing all the software you need to build the container into the container itself (or having a multi-level build system). But for example if I want to use Ansible to configure a container, the easiest way to do that is to actually install Ansible into the container itself, even though Ansible has a large dependency chain most of which we won t need in the container. Yes, Ansible does have a number of connection methods including one for Buildah, but by the point you re using that, you re already using a multi-level build system and aren t really just using a Containerfile.
Okay, so since we re not going to just use a Containerfile, what do we do instead? We produce a CarthageLayout. A CarthageLayout is an object in the Carthage modeling language. The modeling language looks a lot like Python in fact it s even implemented using Python metaclasses and uses the Python parser. However, there are some key semantic differences and it may help to think of the modeling language as its own thing. Carthage layouts are typically contained in Carthage plugins. For example, the oci_images plugin is our focus today. Most of the work in that plugin is in layout.py, and the layout begins here:
class layout(CarthageLayout):
    add_provider(ConfigLayout)
    add_provider(carthage.ansible.ansible_log, str(_dir/"ansible.log"))
The add_provider calls are special, and we ll discuss them in a future post. For now, think of them as assignments in a more complex namespace than simple identifiers. But the heart of this layout is the CarthageImage class:
    class CarthageImage(PodmanImageModel, carthage_base.CarthageServerRole):
        base_image = injector_access('from_scratch_debian')
        oci_image_tag = 'localhost/carthage:latest'
        oci_image_command = ['/bin/systemd']
Most of the work of our image is done by inheritance. We inherit from the CarthageServerRole from the carthage_base plugin collection. A role is a reusable set of infrastructure that can be attached directly to a MachineModel. By inheriting from this role, we request the installation of the Carthage software. The role also supports copying in various dependencies; for example when Carthage is used to manage a cluster of machines, the layout corresponding to the cluster can automatically be copied to all nodes in the cluster. We do not need this feature to build the container image. The CarthageImage class sets its base image. Currently we are using our own base Debian image that we build with debootstrap and then import as a container image. In the fairly near future, we ll change that to:
        base_image =  debian:bookworm 
That will simply use the Debian image from Dockerhub. We are building our own base image for historical reasons and need to confirm that everything works before switching over. By setting oci_image_tag we specify where in the local images the resulting image will be stored. We also specify that this image boots systemd. We actually do want to do a bit of work on top of CarthageServerRole specific to the container image. To do that we use a Carthage feature called a Customization. There are various types of customization. For example MachineCustomization runs a set of tasks on a Machine that is booted and on the network. When building images, the most common type of customization is a FilesystemCustomization. For these, we have access to the filesystem, and we have some way of running a command in the context of the filesystem. We don t boot the filesystem as a machine unless we need to. (We might if the filesystem is a kvm VM or AWS instance for example). Carthage collects all the customizations in a role or image model. In the case of container image classes like PodmanImageModel, each customization is applied as an individual layer in the resulting container image. Roles and customizations are both reusable infrastructure. Roles typically contain customizations. Roles operate at the modeling layer; you might introspect a machine s model or an image s model to see what functionality (roles) it provides. In contrast, customizations operate at the implementation layer. They do specific things like move files around, apply Ansible roles or similar. Let s take a look at the customization applied for the Carthage container image (full code):

        class customize_for_oci(FilesystemCustomization):

            @setup_task("Remove Software")
            async def remove_software(self):
                await self.run_command("apt", "-y", "purge",
                                       "exim4-base",
                                       )

            @setup_task("Install service")
            async def install_service(self):
               # installs and activates a systemd unit
Then to pull it all together, we simply run the layout:
sudo PYTHONPATH=$(pwd) python3 ./bin/carthage-runner ./oci_images build
In the next post, we will dig more into how to make infrastructure reusable.

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29 November 2022

Sam Hartman: Introducing Carthage

For the past four years, I ve been working on Carthage, a free-software Infrastructure as Code framework. We ve finally reached a point where it makes sense to talk about Carthage and what it can do. This is the first in a series of blog posts to introduce Carthage, discuss what it can do and show how it works. Why Another IAC Framework It seems everywhere you look, there are products designed to support the IAC pattern. On the simple side, you could check a Containerfile into Git. Products like Terraform and Vagrant allow you to template cloud infrastructure and VMs. There are more commercial offerings than I can keep up with. We were disappointed by what was out there when we started Carthage. Other products have improved, but for many of our applications we re happy with what Carthage can build. The biggest challenge we ran into is that products wanted us to specify things at the wrong level. For some of our cyber training work we wanted to say things like We want 3 blue teams, each with a couple defended networks, a red team, and some neutral infrastructure for red to exploit. Yet the tools we were trying to use wanted to lay things out at the individual machine/container level. We found ourselves contemplating writing a program to generate input for some other IAC tool. Things were worse for our internal testing. Sometimes we d be shipping hardware to a customer. But sometimes we d be virtualizing that build out in a lab. Sometimes we d be doing a mixture. So we wanted to completely separate the descriptions of machines, networks, and software from any of the information about whether that was realized on hardware, VMs, containers, or a mixture. Dimensional Breakdown In discussing Carthage with Enrico Zini, he pointed me at Cognitive Dimensions of notation as a way to think about how Carthage approaches the IAC problem. I m more interested in the idea of breaking down a design along the idea of dimensions that allow examining the design space than I am particular adherence to Green s original dimensions. Low Viscosity, High Abstraction Reuse One of the guiding principles is that we want to be able to reuse different components at different scales and in different environments. These include being able to do things like: Hidden Dependencies To accomplish these abstraction goals, dependencies need to be non-local. For example, a software role might need to integrate with a directory if a directory is present in the environment. When writing the role, no one is going to know which directory to use, nor whether a directory is present. Taking that as an explicit input into the role is error-prone when the role is combined into large abstract units (bigger roles or collections of machines). Instead it is better to have a non-local dependency, and to find the directory if it is available. We accomplish this using dependency injection. In addition to being non-local, dependencies are sometimes hidden. It is very easy to overwhelm our cognitive capacity with even a fairly simple IAC description. An effective notation allows us to focus on the parts that matter when working with a particular part of the description. I ve found hiding dependencies, especially indirect dependencies, to be essential in building complex descriptions. Obviously, tools are required for examining these dependencies as part of debugging. First Class Modeling Clearly one of the goals of IAC descriptions is to actually build and manage infrastructure. It turns out that there are all sorts of things you want to do with the description well before you instantiate the infrastructure. You might want to query the description to build network diagrams, understand interdependencies, or even build inventory/bill of materials. We often find ourselves building Ansible inventory, switch configurations, DNS zones, and all sorts of configuration artifacts. These artifacts may be installed into infrastructure that is instantiated by the description, but they may be consumed in other ways. Allowing the artifacts to be consumed externally means that you can avoid pre-commitment and focus on whatever part of the description you originally want to work on. You may use an existing network at first. Later the IAC description may replace that, or perhaps it never will. As a result, Carthage separates modeling from instantiation. The model can generally be built and queried without needing to interact with clouds, VMs, or containers. We ve actually found it useful to build Carthage layouts that cannot ever be fully instantiated, for example because they never specify details like whether a model should be instantiated on a container or VM, or what kind of technology will realize a modeled network. This allows developing roles before the machines that use them or focusing on how machines will interact and how the network will be laid out before the details of installing on specific hardware. The modeling separation is by far the difference I value most between Carthage and other systems. A Tool for Experts. In Neal Stephenson s essay In the Beginning Was the Command Line , Stephenson points out that the kind of tools experts need are not the same tools that beginners need. The illustration of why a beginner might not be satisfied with a Hole Hog drill caught my attention. Carthage is a tool for experts. Despite what cloud providers will tell you, IAC is not easy. Doubly so when you start making reusable components. Trying to hide that or focus on making things easy to get started can make it harder for experts to efficiently solve the problems they are facing. When we have faced trade offs between making Carthage easy to pick up and making it powerful for expert users, we have chosen to support the experts. That said, Carthage today is harder to pick up than it needs to be. It s a relatively new project with few external users as of this time. Our documentation and examples need improvement, just like every project at this level of maturity. Similarly, as the set of things people try to do expand, we will doubtless run into bugs that our current test cases don t cover. So Carthage absolutely will get easier to learn and use than it is today. Also, we ve already had success building beginner-focused applications on top of Carthage. For our cyber training, we built web applications on top of Carthage that made rebuilding and exploring infrastructure easy. We ve had success using relatively understood tools like Ansible as integration and customization points for Carthage layouts. But in all these cases, when the core layout had significant reusable components and significant complexity in the networking, only an IAC expert was going to be able to maintain and develop that layout. What Carthage can do. Carthage has a number of capabilities today. One of Carthage s strengths is its extensible design. Abstract interfaces make it easy to add new virtualization platforms, cloud services, and support for various ways of managing real hardware. This approach has been validated by incrementally adding support for virtualization architectures and cloud services. As development has progressed, adding new integrations continues to get faster because we are able to reuse existing infrastructure. Today, Carthage can model: Carthage has excellent facilities for dealing with images on which VMs and Containers can be based, although it does have a bit of a Debian/Ubuntu bias in how it thinks about images: When instantiating infrastructure, Carthage can work with: We have also looked at Oracle Cloud and I believe Openstack, although that code is not merged. Future posts will talk about core Carthage concepts and how to use Carthage to build infrastructure.

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10 June 2022

Sam Hartman: Flailing to Replace Jack with Pipewire for DJ Audio

I could definitely use some suggestions here, both in terms of things to try or effective places to ask questions about Pipewire audio. The docs are improving, but are still in early stages. Pipewire promises to combine the functionality of PulseAudio and Jack. That would be great for me. I use Jack for my DJ work, and it s somewhat complicated and fragile. However, so far my attempts to replace Jack have been unsuccessful, and I might need to even use PulseAudio instead of Pipewire to get the DJ stuff working correctly. The Setup In the simplest setup I have a DJ controller. It s both a MIDI device and a sound card. It has 4 channel audio, but it s not typical surround sound. Two channels are the main speakers, and two channels are the headphones. Conceptually it might be better to model the controller as two sinks: one for the speakers and one for the headphones. At a hardware level they need to be one device for several reasons, especially including using a common clock. It s really important than only the main mix go out channel 1-2 (the speakers). Random beeps or sound from other applications going out the main speakers is disruptive and unprofessional. However, because I m blind, I need that sound. I especially need the output of Orca (my screen reader) and Emacspeak (another screen reader). So I need that output to go to the headphones. Under Pulse/Jack The DJ card is the Jack primary sound device (system:playback_1 through system:playback_4). I then use themodule-jack-sink Pulse module to connect Pulse to Jack. That becomes the default sink for Pulse, and I link front-left from that sink to system:playback_3. So, I get the system sounds and screen reader mixed into the left channel of my headphones and nowhere else. Enter Pipewire Initially Pipewire sees the DJ card as a 4-channel sound card and assumes it s surround4.0 (so front and rear left and right). It helpfully expands my stereo signal so that everything goes to the front and rear. So, exactly what I don t want to have happen happens: all my system sounds go out the main speakers (channel 1-2). It was easy to override Wireplumber s ALSA configuration and assign different channel positions. I tried assigning something like a1,a2,fl,fr hoping that Pipewire wouldn t mix things into aux channels that weren t part of the typical surround set. No luck. It did correctly reflect the channels in things like pacmd list sinks so my Pipewire config was being applied. But the sound was still wrong. * I tried turning off channelmix.upmix. That didn t help; that appears to be more about mixing stereo into center, rear and LFE. The basic approach of getting a stream to conform to the output node s channels appears to be hurting me here. I d love any ideas about how I can get this to work. I m sure it s simple I m just missing the right mental model or knowledge of how to configure things. Pipewire Not Talking to Jack I thought I could at least use Pipewire the same way I use Pulse. Namely, I can run a real jackd and connect up Pipewire to that server. According to the wiki, Pipewire can be a Jack client. It s disabled by default, because you need to make sure that Wireplumber is using the real Jack libraries rather than the Pipewire replacements. That s the case on Debian, so I enabled the feature. A Jack device appeared in wpctl status as did a Jack sink. Using jack_lsp on that device showed it was talking to the Jack server and connected to system:playback_*. Unfortunately, it doesn t work. The sink does not show up in pacmd list sinks, and pipewire-pulse gives an error about it not being ready. If I select it as the default sink in wpctl set-default I get no sound at all, at least from Pulse applications. Versions of things This is all on debian, approximately testing/bookworm or newer for the relevant libraries.

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21 March 2022

Gunnar Wolf: Long, long, long live Emacs after 39 years

Reading Planet Debian (see, Sam, we are still having a conversation over there? ), I read Anarcat s 20+ years of Emacs. And.. Well, should I brag contribute to the discussion? Of course, why not? Emacs is the first computer program I can name that I ever learnt to use to do something minimally useful. 39 years ago.
From the Space Cadet keyboard that (obviously ) influenced Emacs early design
The Emacs editor was born, according to Wikipedia, in 1976, same year as myself. I am clearly not among its first users. It was already a well-established citizen when I first learnt it; I am fortunate to be the son of a Physics researcher at UNAM, My father used to take me to his institute after he noticed how I was attracted to computers; we would usually spend some hours there between 7 and 11PM on Friday nights. His institute had a computer room where they had very sweet gear: Some 10 Heathkit terminals quite similar to this one: The terminals were connected (via individual switches) to both a PDP-11 and a Foonly F2 computers. The room also had a beautiful thermal printer, a beautiful Tektronix vectorial graphics output terminal, and some other stuff. The main user for my father was to typeset some books; he had recently (1979) published Integral Transforms in Science and Engineering (that must be my first mention in scientific literature), and I remember he was working on the proceedings of a conference he held in Oaxtepec (the account he used in the system was oax, not his usual kbw, which he lent me). He was also working on Manual de Lenguaje y Tipograf a Cient fica en Castellano, where you can see some examples of TeX; due to a hardware crash, the book has the rare privilege of being a direct copy of the output of the thermal printer: It was not possible to produce a higher resolution copy for several years But it is fun and interesting to see what we were able to produce with in-house tools back in 1985! So, what could he teach me so I could use the computers while he worked? TeX, of course. No, no LaTeX (that was published in 1984). LaTeX is a set of macros developed initially by Leslie Lamport, used to make TeX easier; TeX was developed by Donald Knuth, and if I have this information correct, it was Knuth himself who installed and demonstrated TeX in the Foonly computer, during a visit to UNAM. Now, after 39 years hammering at Emacs buffers Have I grown extra fingers? Nope. I cannot even write decent elisp code, and can barely read it. I do use org-mode (a lot!) and love it; I have written basically five books, many articles and lots of presentations and minor documents with it. But I don t read my mail or handle my git from Emacs. I could say, I m a relatively newbie after almost four decades. Four decades When we got a PC in 1986, my father got the people at the Institute to get him memacs (micro-emacs). There was probably a ten year period I barely used any emacs, but always recognized it. My fingers hve memorized a dozen or so movement commands, and a similar number of file management commands. And yes, Emacs and TeX are still the main tools I use day to day.

14 March 2022

Sam Hartman: Nostalgia for Blogging

Recently, I migrated this blog from Livejournal over to Dreamwidth. As part of the process, I was looking back at my blog entries from around 2007 or so.
I miss those days. I miss the days when blogging was more of an interactive community. Comments got exchanged, and at least among my circle of friends people wrote thoughtful, well-considered entries. There was introspection into what was going on in people's lives, as well as technical stuff, as well as just keeping up with people who were important in my life.
Today, we have some of the same thought going into things like Planet Debian, but it's a lot less interactive. Then we have things like Facebook, Twitter, and the more free alternatives. There's interactivity, but it feels like everything has to fit into the length of a single tweet. So it is a lot faster paced and a lot less considered. I find I don't belong to that fast-paced social media as much as I did to the blogs of old.

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13 March 2022

Sam Hartman: Migrating to Dreamwidth

I am migrating my blog to Dreamwidth. I have a lot of fond memories of Livejournal over the years, and miss the world of blogging that was.
Over the years, Livejournal has become more commercial and has been less associated with my community values. I never left during the mass exoduses around TOS changes because while I saw things changing, the worst terms seemed in response to government regulation rather than the choices of the company. I know that if I were to look into US laws, I'd find several that I object to as well.
Ultimately, concerns around the current conflict and around the stability of Russia as a hosting location tipped the balance. I do not support the decisions of the Russian government, and regardless of whether Livejournal does support the conflict or not, stability is also a concern in platform selection.

28 April 2021

Russell Coker: Links April 2021

Dr Justin Lehmiller s blog post comparing his official (academic style) and real biographies is interesting [1]. Also the rest of his blog is interesting too, he works at the Kinsey Institute so you know he s good. Media Matters has an interesting article on the spread of vaccine misinformation on Instagram [2]. John Goerzen wrote a long post summarising some of the many ways of having a decentralised Internet [3]. One problem he didn t address is how to choose between them, I could spend months of work to setup a fraction of those services. Erasmo Acosta wrote an interesting medium article Could Something as Pedestrian as the Mitochondria Unlock the Mystery of the Great Silence? [4]. I don t know enough about biology to determine how plausible this is. But it is a worry, I hope that humans will meet extra-terrestrial intelligences at some future time. Meredith Haggerty wrote an insightful Medium article about the love vs money aspects of romantic comedies [5]. Changes in viewer demographics would be one factor that makes lead actors in romantic movies significantly less wealthy in recent times. Informative article about ZIP compression and the history of compression in general [6]. Vice has an insightful article about one way of taking over SMS access of phones without affecting voice call or data access [7]. With this method the victom won t notice that they are having their sservice interfered with until it s way too late. They also explain the chain of problems in the US telecommunications industry that led to this. I wonder what s happening in this regard in other parts of the world. The clown code of ethics (8 Commandments) is interesting [8]. Sam Hartman wrote an insightful blog post about the problems with RMS and how to deal with him [9]. Also Sam Whitton has an interesting take on this [10]. Another insightful post is by Selam G about RMS long history of bad behavior and the way universities are run [11]. Cory Doctorow wrote an insightful article for Locus about free markets with a focus on DRM on audio books [12]. We need legislative changes to fix this!

24 March 2021

Sam Hartman: Making our Community Safe: the FSF and rms

I felt disgust and horror when I learned yesterday that rms had returned to the FSF board. When rms resigned back in September of 2019, I was Debian Project Leader. At that time, I felt two things. First, I was happy that the community was finally taking a stand in favor of inclusion, respect, and creating a safe, welcoming place to do our work. It was long past time for rms to move on. But I also felt thankful that rms was not my problem to solve. In significant part because of rms, I had never personally been that involved in the FSF. I considered drafting a statement as Debian Project Leader. I could have talked about how through our Diversity Statement and Code of Conduct we had taken a stand in favor of inclusion and respect. I could have talked about how rms's actions displayed a lack of understanding and empathy and how this created a community that was neither welcoming nor respectful. I didn't. I guess I didn't want to deal with confirming I had sufficient support in the project. I wanted to focus on internal goals, and I was healing and learning from some mistakes I made earlier in the year. It looked like other people were saying what needed to be said and my voice was not required. Silence was a mistake.

It's a mistake I've been making all throughout my interactions with rms. Enough is enough. It's long past time I added my voice to those who cry for accountability and who will not sit aside while rms's disrespect and harm is tolerated.

The first time I was silent about rms was around 15 years ago. I was at a science fiction convention in a crowded party. I didn't know anyone, other than the host of the party. I was out of my depth. I heard his voice---I recognized it from the Share the Software Song. He was hitting on some girl, talking about how he invented Emacs. As best I could tell, she didn't even know what Emacs was. Back then, I wondered what she saw in the interaction; why she stuck around even though she didn't know what he was talking about. I sure didn't want to be around; the interaction between the two of them was making me uncomfortable. Besides, the wings on her costume kept hitting me in the face. So I left as fast as I could.

I've learned a lot about creating safe spaces and avoiding sexual harassment since then. Thinking back, she was probably hitting me because she was trying to back away and getting crowded. If this happened today, I think I would do a better job of owning my responsibility for helping keep the space around me safe. I've learned better techniques for checking in to make sure people around me are comfortable.

I didn't come to silence alone: I had been educated into the culture of avoiding rms and not calling him out. There was a running game in the group of computer security professionals I learned from. The goal was to see how much you could contribute to free software and computer security without being recognized by or interacting with rms. And so, indoctrinated into a culture of silence about the harm that rms caused, I took my first step.

Things weren't much better when I attended Libreplanet 2019 just before taking office as Debian Project Leader. I had stayed away from the conference in large part because of rms. But there were Debian people there, and I was missing community interaction. Unfortunately, I saw that even after the problems of 2018, rms was still treating himself as above community standards. He interrupted speakers, objecting to how they phrased the problem they were considering. After a speech on codes of conduct in the free software community, he cornered the talk organizer to "ask her opinion" about the GNU project's lack of code on conduct. He wasn't asking for an opinion. He was justifying himself; there wasn't much listening in the conversation I heard. Aspects of that conversation crossed professional boundaries for what should be said. The talk organizer was okay--we talked about it after--but if we did a better job of policing our community, that wouldn't even be a question. I think the most telling sign was a discussion with an FSF board member. We were having a great conversation, but he had to interrupt it. He was on rms duty (my words) at the next session. The board had decided it was necessary to have members there so that the staff would not be put in awkward positions by their president. If someone needed to call rms out, it could be a board member rather than the staff members of the conduct team.

And yet again, I held my silence. It's so easy to keep silent. It's not that I never speak up. There are communities where I have called people out. But it's hard to paint that target on yourself. It's hard to engage and to stand strong for a community's standards when you aren't the target. It's hard to approach these problems while maintaining empathy for everyone involved. Some people give into the rage; I don't have that option if I want to be the person I've chosen to be. And so, when I do speak up, the emotional cost is high.

Yet, it's long past time I raised my voice on this issue. Rms has demonstrated that he cannot hold to standards of respect for others, respect for their boundaries, or standards of community safety. We need those standards to be a welcoming community.

If the people who came before me--those who taught me the game of avoiding rms--had spoken up, the community could have healed before I even came on the scene. If I and others had stood up fifteen years ago, we'd have another couple generations who were more used to respect, inclusion, welcoming and safety. The FSF board could have done their job back in 2018. And perhaps if more of us had spoken out in 2019, the FSF board would have found the strength to stand strong and not accept rms's return.

And so, finally, I raise my voice. I signed the open letter calling for the resignation of rms and the entire FSF board. Perhaps if we all get used to raising our voice, it will be easier. Perhaps if we stand together, taking the path of community rather than the path of silence, we'll have the support we need to create communities inclusive enough to welcome everyone who can contribute. For me, I'm done being silent.

There's one criticism of the open letter I'd like to respond to. I've heard concerns about asking for the resignation of the entire FSF board under the understanding that some board members voted against rms's return. It should be obvious why those who voted for rms's return need to resign. But resignation does not always mean you did something wrong. If you find yourself in a leadership role in an organization that takes decisions in significant conflict with your standards of ethics, resignation is also the right path. Staying on the board even if you voted against rms's return means that you consider voting for rms to be a reasonable thing to do. It means that even if you disagreed with it, you can still be part of an organization that takes the path of welcoming rms. At this point, I cannot do that, nor can I support leaders in the FSF who do.

6 August 2020

Sam Hartman: Good Job Debian: Compatibility back to 1999

So, I needed a container of Debian Slink (2.1), released back in 1999. I expected this was going to be a long and involved process. Things didn't look good from the start:
root@mount-peerless:/usr/lib/python3/dist-packages/sqlalchemy# debootstrap  slink /build/slink2 
http://archive.debian.org/debian                                                               
E: No such script: /usr/share/debootstrap/scripts/slink

Hmm, I thought I remembered slink support for debootstrap--not that slink used debootstrap by default--back when I was looking through the debootstrap sources years ago. Sure enough looking through the changelogs, slink support was dropped back in 2005.
Okay, well, this isn't going to work either, but I guess I could try debootstrapping sarge and from there go back to slink.
Except it worked fine.
Go us!

9 March 2020

Sam Hartman: Forged Email

Last night, a series of forged emails was sent to a number of places around the Debian, Ubuntu and Free Software communities. The meat of the mail was a fake message from me to debian-private with the subject "DebConf19 Diversity Girls." I didn't write such a message.
I view this message as the latest installment in a campaign of attacks on Debian that attempt to undermine the project and take up the time of our members.
I was expecting something like this: yesterday, I banned Daniel Pocock from the project.There's been a pattern of related events over the past year and a half:

27 October 2017

Sam Hartman: How Can Debian Turn Disagreement into Something that Makes us Stronger

Recently, when asked to engage with the Debian Technical Committee, a maintainer chose to orphan their package rather than discuss the issue brought before the committee. In another decision earlier this year, a maintainer orphaned their package indicating a lack of respect for the approach being taken and the process. Unfortunately, this joins an ever longer set of issues where people walk away from the TC process disheartened and upset.

For me personally the situations where maintainers walked away from the process were hard. People I respect and admire were telling me that they were unwilling to participate in our dispute resolution process. In one case the maintainer explicitly did not respect a process I had been heavily involved in. As someone who values understanding and build a team, I feel disappointed and hurt thinking about this.

Unfortunately, I don't feel much better when I consider several of the other issues brought before the TC. In a number of cases, the process has concluded, but it feels like a pyrrhic victory. We have an answer, but often we never reached an understanding of one of the key stakeholder's positions. People are sufficiently disappointed or frustrated that they reduce their involvement. That is, the answer is not one they can live with. Sometimes, I'm not even sure that answering the question was worth the cost.

My initial suspicion as I begin to consider issues that have come before the TC in the last few years is that as a necessary consequence of how the TC operates, we will drive a significant chunk of those who come to us away from our community. I will not be part of that. If I end up eventually agreeing with this suspicion, I will either work to improve the TC process or find a different way to contribute to the project that is more aligned with my goals.


Our Community is More Important than Technical Correctness I firmly believe that Debian's strength is its community. Distributions, upstreams, free-software advocates, corporate interests, and everything in between work together. Because we are working on a concrete product,we actually have to understand how our needs conflict and compliment each other. Also, like any organization, our ability to get things done is dependent on our contributors and the time we all put in.

I cannot think of anything more harmful we can do than drive away a constructive contributor. Technical quality is important: many of us will eventually go away if quality drops too much. However, Debian itself can be improved incrementally. Yes, new people do join Debian. However, it takes a lot of new people to make up for a situation where everyone involved is frustrated, and some leave and tell their friends to stay away from Debian.

When a Disagreement Reaches the TC When a disagreement reaches the TC, we know a few things. First, people have not have not been able to resolve it on their own. Second, the disagreement is important enough to at least one of the parties to ask for outside help.

If the TC were to simply announce a decision, it is very likely that at least one party would feel frustrated and disappointed. If the decision is important to someone it almost always means that they care about the outcome. If previous efforts have not reached agreement then there is an outcome that is undesired. While it's possible under the constitution that two parties could bring an issue to the TC mutually where the dynamics could be different, this does not happen in practice.

When we "lose" When a decision making process decides to select one of my undesired outcomes, I have strong negative feelings. First, there is the technical result itself. Because of an adverse decision it is generally harder for me to do my technical work, or some ethical position or group I care about is disadvantaged. However, the strongest feelings are related to needs about my place in the community, not a direct response to the technical decision. I worry about whether issues I care about will be valued in the future; I would likely feel weary or scared thinking of contributing in an environment where issues that matter to me aren't going to be considered. I tend to feel frustrated if my position was not adequately considered this time around.

Often, the strongest feelings do not stem from how I am impacted by the decision itself. Thus, if my more general needs are addressed, I will feel a lot better about not having my preferred outcome selected. Confidence that my position was understood is the single biggest factor in being able to accept the result. If the community took the time to understand me, then I have confidence that I am valued. I can advocate for change and be part of the ongoing discussion. If I understand the other positions then I can understand that the position was not arbitrary. Understanding the other positions is also a prerequisite to seeing how things I value were considered, especially when the tradeoff did not ultimately favor these values.

My conversations with others about their experience with conflict suggest my feelings and needs are common.


However, the TC focuses almost exclusively on the technical matter before it. I don't think the TC has done a good job of actually understanding maintainers or the people bringing issues to us. Especially when we're fairly sure we understand what the ultimate decision will be, we focus on getting to that decision. Of course part of actually understanding someone is considering what they have to say. Even when you have high confidence in an outcome, if you want someone to feel understood, you do have to listen at a point where you can consider what they bring forward.

Frustration of Being Questioned

On the other side, it's frustrating to have your decisions questioned. Reviewing a decision takes time. Even if the TC agrees with a maintainer, asking that maintainer to sit through a long process can create frustrations as deep as any I discussed in the previous section.

So the process is doubly bad for maintainers. Someone can bring up an issue which requires precious time. Then if the TC decides against the maintainer, we have all the problems I discussed previously.

I acknowledge this. A good process must respect the maintainer's time. However, it must respect the community members who disagree with maintainers. Everyone who brings an issue to the TC is a developer. They have contributed significantly to our community and are part of our team. Yes, we need to protect the process against abuse. But in a very real sense if we aren't willing to consider an issue and we aren't willing to engage with someone, understand why they think the issue should be considered, and work until they understand why we made our decision, we are saying we do not respect them enough to take that time. We should expect that to drive people away.

I wonder if the solution here involves a two phase process. During the first phase we work with someone bringing an issue to us until we understand it. We either engage the maintainer at that point, spend the time to help the person bringing an issue to us understand why we are not engaging the maintainer, or have decided the issue is abusive of the processs/misdirected. For this to work maintainers would have to trust us enough to actually be willing to sit back and not spend a lot of their time.

Sam, It's Just Personalities

One criticism I've heard as I discuss this is that a lot of the negative feelings surround interpersonal conflict and are personality conflicts. Yes, personalities matter. Yes, we re still healing from the Systemd discussion.

However, as a community, I think we need to figure out how we respect the inevitable personality conflicts. I can think of one or two developers I'm still upset with years after an issue. It happens. Perhaps if I were a maintainer when one of these developers raised a concern with my packages, I could ask that someone else be a primary advocate for an issue. Similarly, if a developer wanted to address an issue with me as a maintainer but would prefer not to deal with me, perhaps we could figure out some way that we could see if someone else shared the concern.

Dropping a Package is Sometimes an Answer

My concerns were sparked by instances where a maintainer dropped a package rather than interact with the TC. Sometimes that can be a healthy step in a transition. At Debconf this year, Enrico Zini gave a talk on consent culture in Debian. One of the key points of his talk is that we can find over time that what we're being asked to do in Debian is no longer consistent with our boundaries. If it isn t helping us move forward if it isn t fun then it is likely time to stop.

In that sense, approaching disagreement can be a great time to take stock and ask whether we still enjoy maintaining a package. If we don t, then stepping aside and letting others take it on can be a great way that we and they can be happier. I don t really think that s what happened in these instances though. Based on comments made to me, this sounded more like a lack of faith in being treated well or in our ability as a committee.

Even so, Enrico s talk applies in a number of ways here. He suggests that the approach we should take when someone is done and steps away is to thank then. I couldn t agree more. From the depth of my heart I offer thanks: Thank you for taking care of yourself and stepping away when it is no longer fun. Thank you for all the effort you have put into these packages. I hope to work with you on great things in the future.

12 August 2017

Sam Hartman: Debian: a Commons of Innovation

I recently returned from Debconf. This year at Debconf, Matthew Garrett gave a talk about the next twenty years in free software. In his talk he raised concerns that Debian might not be relevant in that ecosystem and talked about some of the trends that contribute to his concerns.
I was talking to Marga after the talk and she said that Debian used to be a lot more innovative than it is today.
My initial reaction was doubt; what she said didn't feel right to me. At the time I didn't have a good answer. Since then I've been pondering the issue, and I think I have a partial answer to both Marga and Matthew and so I'll share it here.
In the beginning Debian focused on a lot of technical innovations related to bringing an operating system together. We didn't understand how to approach builds and build dependencies in a uniform manner. Producing packages in a clean environment was hard. We didn't understand what we wanted out of packages in terms of a uniform approach to configuration handling and upgrades. To a large extent we've solved those problems.
However, as the community has grown, our interests are more diverse. Our users and free software (and the operating system we build together) are what bring us together: we still have a central focus. However, no one technical project captures us all. There's still significant technical innovation in the Debian ecosystem. That innovation happens in Debian teams, companies and organizations that interact with the Debian community. We saw several talks about such innovation this year. I found the talk about ostree and flatpak interesting, especially because it focused on people in the broader Debian ecosystem valuing Debian along with some of the same technologies that Matthew is worried will undermine our relevance.
Matthew talked about how Debian ends up being a man-in-the-middle. We're between users and developers. we're between distributions and upstreams. Users are frustrated because we hold back the latest version of software they want from getting to them. Developers are frustrated because we present our users with old versions of their software configured not as they would like, combined with different dependencies than they expect.
All these weaknesses are real.
However, I think Debian-in-the-middle is our greatest strength both on the technical and social front.
I value Debian because I get a relatively uniform interface to the software I use. I can take one approach to reporting bugs whether they are upstream or Debian specific. I expect the software to behave in uniform ways with regard to things covered by policy. I know that I'm not going to have to configure multiple different versions of core dependencies; for the most part system services are shared. When Debian has value it's because our users want those things we provide. Debian has also reviewed every source file in the software we ship to understand the license and license compatibility. As a free software supporter and as someone who consumes software in commercial context, that value alone is enormous.
The world has evolved and we're facing technologies that provide different models. They've been coming for years: Python, Ruby, Java, Perl and others have been putting together their own commons of software. They have all been working to provide virtualization to isolate one program (and its dependencies) from another. Containerization takes that to the next level. Sometimes that's what our users want.
We haven't figured out what the balances are, how we fit into this new world. However, I disagree with the claim that we aren't even discussing the problem. I think we're trying a lot of things off in our own little technical groups. We're just getting to the level of critical mass of understanding where we can take advantage of Debian's modern form of innovation.
Because here's the thing. Debian's innovation now is social, not technical. Just as we're in the middle technically, we're in the middle socially. Upstreams, developers, users, derivatives, and all the other members of our community work together. we're a place where we can share technology, explore solutions, and pull apart common elements. This is the first Debconf where it felt like we'd explored some of these trends enough to start understanding how they might fit together in a whole. Seven years ago, it felt like we were busy being convinced the Java folks were wrong-headed. A couple of years later, it felt like we were starting to understand our users' desires that let to models different than packaging, but we didn't have any thoughts. At least in my part of the hallway it sounded like people were starting to think about how they might fit parts together and what the tradeoffs would be.
Yes, Matthew's talk doubtless sparked some of that. I think he gave us a well deserved and important wake-up call. However, I was excited by the discussion prior to Thursday.
What I'm taking a way is that Debian is valuable when there's a role in the middle. Both socially and technically we should capitalize on situations where something between makes things better and get out of the way where it does not.

9 April 2017

Sam Hartman: When "when" is too hard a question: SQLAlchemy, Python datetime, and ISO8601

A new programmer asked on a work chat room how timezones are handled in databases. He asked if it was a good idea to store things in UTC. The senior programmers all laughed as we told some of our horror stories with timezones. Yes, UTC is great; if only it were that simple.
About a week later I was designing the schema for a blue sky project I'm implementing. I had to confront time in all its Pythonic horror.
Let's start with the datetime.datetime class. Datetime objects optionally include a timezone. If no timezone is present, several methods such as timestamp treat the object as a local time in the system's timezone. The timezone method returns a POSIX timestamp, which is always expressed in UTC, so knowing the input timezone is important. The now method constructs such an object from the current time.
However other methods act differently. The utcnow method constructs a datetime object that has the UTC time, but is not marked with a timezone. So, for example datetime.fromtimestamp(datetime.utcnow().timestamp()) produces the wrong result unless your system timezone happens to have the same offset as UTC.
It's also possible to construct a datetime object that includes a UTC time and is marked as having a UTC time. The utcnow method never does this, but you can pass the UTC timezone into the now method and get that effect. As you'd expect, the timestamp method returns the correct result on such a datetime.
Now enter SQLAlchemy, one of the more popular Python ORMs. Its DATETIME type has an argument that tries to request a column capable of storing a a timezone from the underlying database. You aren't guaranteed to get this though; some databases don't provide that functionality. With PostgreSQL, I do get such a column, although something in SQLAlchemy is not preserving the timezones (although it is correctly adjusting the time). That is, I'll store a UTC time in an object, flush it to my session, and then read back the same time represented in my local timezone (marked as my local timezone). You'd think this would be safe.
Enter SQLite. SQLite makes life hard for people wanting to store time; it seems to want to store things as strings. That's fairly incompatible with storing a timezone and doing any sort of comparisons on dates. SQLAlchemy does not try to store a timezone in SQLite. It just trims any timezone information from the datetime. So, if I do something like
d = datetime.now(timezone.utc)
obj.date_col = d
session.add(obj)
session.flush()
assert obj.date_col == d # fails
assert obj.date_col.timestamp() == d.timestamp() # fails
assert d == obj.date_col.replace(tzinfo = timezone.utc) # finally succeeds

There are some unfortunate consequences of this. If you mark your datetimes with timezone information (even if it is always the same timezone), whether two datetimes representing the same datetime compare equal depends on whether objects have been flushed to the session yet. If you don't mark your objects with timezones, then you may not store timezone information on other databases.
At least if you use only the methods we've discussed so far, you're reasonably safe if you use local time everywhere in your application and don't mark your datetimes with timezones. That's undesirable because as our new programmer correctly surmised, you really should be using UTC. This is particularly true if users of your database might span multiple timezones.
You can use UTC time and not mark your objects as UTC. This will give the wrong data with a database that actually does support timezones, but will sort of work with SQLite. You need to be careful never to convert your datetime objects into POSIX time as you'll get the wrong result.
It turns out that my life was even more complicated because parts of my project serialize data into JSON. For that serialization, I've chosen ISO 8601. You've probably seen that format: '2017-04-09T18:17:27.340410+00:00. Datetime provides the convenient isoformat method to print timestamps in the ISO 8601 format. If the datetime has a timezone indication, it is included in the ISO formatted string. If not, then no timezone indication is included. You know how I mentioned that datetime takes a string without a timezone marker as local time? Yeah, well, that's not what 8601 does: UTC all the way, baby! And at least the parser in the iso8601 module will always include timezone markers. So, if you use datetime to print a timestamp without a timezone marker and then read that back in to construct a new datetime on the deserialization side, then you'll get the wrong time. OK, so mark things with timezones then. Well, if you use local time, then the time you get depends on whether you print the ISO string before or after session flush (before or after SQLAlchemy trims the timezone information as it goes to SQLite).
It turns out that I had the additional complication of one side of my application using SQLite and one side using PostgreSQL. Remember how I mentioned that something between SQLAlchemy and PostgreSQL was recasting my times in local timezone (although keeping the time the same)? Well, consider how that's going to work. I serialize with the timezone marker on the PostgreSQL side. I get a ISO8601 localtime marked with the correct timezone marker. I deserialize on the SQLite side. Before session flush, I get a local time marked as localtime. After session flush, I get a local time with no marking. That's bad. If I further serialize on the SQLite side, I'll get that local time incorrectly marked as UTC. Moreover, all the times being locally generated on the SQLite side are UTC, and as we explored, SQLite really only wants one timezone in play.
I eventually came up with the following approach:

  1. If I find myself manipulating a time without a timezone marking, assert that its timezone is UTC not localtime.

  2. Always use UTC for times coming into the system.

  3. If I'm generating an ISO 8601 time from a datetime that has a timezone marker in a timezone other than UTC, represent that time as a UTC-marked datetime adjusting the time for the change in timezone.


This is way too complicated. I think that both datetime and SQLAlchemy's SQLite time handling have a lot to answer for. I think SQLAlchemy's core time handling may also have some to answer for, but I'm less sure of that.

29 January 2017

Sam Hartman: Network Audio Visualization: Network Modeling

Previously, I wrote about my project to create an audio depiction of network traffic. In this second post, I explore how I model aspects of the network that will be captured in the audio representation. Before getting started, I'll pass along a link. This is not the first time someone has tried to put sound to packets flying through the ether: I was pointed at Peep. I haven't looked at Peep, but will do so after I finish my own write up. Not being an academic, I feel no obligation to compare and contrast my work to others:-)
I started with an idea of what I'd like to hear. One of my motivations was to explore some automated updates we run at work. So, I was hoping to capture the initial DNS and ARP traffic as the update discovered the systems it would contact. Then I was hoping to capture the ssh and other traffic of the actual update.
To Packet or Stream
One of the simplest things to do would simply be to model network packets. For DNS I chose that approach. I was dubious that a packet-based model would capture the aspects of TCP streams I typically care about. I care about the source and destination (both address and port) of course. However I also care about how much traffic is being carried over the stream and the condition of the stream. Are there retransmits? Are there a bunch of unanswered SYNs? But I don't care about the actual distribution of packets. Also, a busy TCP stream can generate thousands of packets a second. I doubted my ability to distinguish thousands of sounds a second at all, especially while trying to convey enough information to carry stream characteristics like overall traffic volume.
So, for TCP, I decided to model some characteristics of streams rather than individual packets.
For DNS, I decided to represent individual requests/replies.
I came up with something clever for ARPP. There, I model the request/reply as an outstanding request. A lot of unanswered ARPs can be a sign of a scan or a significant problem. The mornful sound of a TCP stream trailing off into an unanswered ARP as the cache times out on a broken network is certainly something I'd like to capture. So, I track when an ARP request is sent and when/if it is answered.
Sound or Music
I saw two approaches. First, I could use some sound to represent streams. As an example, a running diesel engine could make a great representation of a stream. The engine speed could represent overall traffic flow. There are many opportunities for detuning the engine to represent various problems that can happen with a stream. Perhaps using stereo separation and slightly different fundamental frequencies I could even represent a couple of streams and still be able to track them.
However, at least with me as a listener, that's not going to scale to a busy network. The other option I saw was to try and create melodic music with various musical phrases modified as conditions within the stream or network changed. That seemed a lot harder to do, but humans are good at listening to complicated music.
I ended up deciding that at least for the TCP streams, I was going to try and produce something more musical than sound. I was nervous: I kept having visions of a performance of "Peter and the Wolf" with different instruments representing all the characters that somehow went dreadfully wrong.
As an aside, the decision to approach music rather than sound depended heavily on what I was trying to capture. If I'm modeling more holistic properties of a system--for example, total network traffic without splitting into streams--I think parameterized sounds would be a better approach.
The decision to approach things musically affected the rest of the modeling. Somehow I was going to need to figure out notes to play. I'd already rejected the idea of modeling packets, so I wouldn't simply be able to play notes when a packet arrived.
Energy Decay
As I played with various options, I realized that the critical challenge would be figuring out how to focus the listener's attention on the important aspects of what was going on. Clutter was the great enemy. My job would be figuring out how to spend sound wisely. When something interesting happened, that part of the model should get more focus--more of the listener's energy.
Soon I found myself thinking a lot about managing the energy of network streams. I imagined streams getting energy when something happened, and spending that energy to convey that interesting event to the listener. Energy needed to accumulate fast enough that even low-traffic streams could be noticed. Energy needed to be spent fast enough that old events were not taking listener focus from new, interesting things going on. However, if the energy were spent slow enough, then network events could be smoothed out to give a better picture of the stream rather than individual packets.
This concept of managing some decaying quantity and managing the rate of decay proved useful at multiple levels of the model.
Two Layer Model
I started with a python script that parses tcpdump output. It associates a packet with a stream and batches packets together to avoid overloading other parts of the system.
The output of this script are stream events. Events include a source and destination address, a stream ID, traffic in each direction, and any special events on the stream.
For DNS, the script just outputs packet events. For ARP, the script outputs request start, reply, and timeout events. There's some initial support for UDP, but so far that doesn't make sound.
Right now, FINs are modeled, but SYNs and the interesting TCP conditions aren't directly modeled. If you get retransmissions you'll notice because packet flow will decrease. However, I'd love to explicitly sound retransmissions. I also think a window filling as an application fails to read is important. I imagine either narrowing a band-pass filter to clamp the audio bandwidth available to a stream with a full window. Or perhaps taking it the other direction and adding an echo.
The next layer down tracks the energy of each stream. But that, and how I map energy into music, is the topic of the next post.

Next.