1. 2019-03-17

    Docker.io's ugly power grab

    I recently spent a little while troubleshooting the battery life on my vintage ThinkPad x230 which is running Debian linux buster, as the power drain seemed to be mysteriously high. After poking around with the diagnostic tools, I was suprised to find according to powertop an ethernet device called nic:docker0 was consuming between 2-4W of power according to PowerTOP. This was occuring even with the docker service stopped or disabled and with docker network listing no networks.

    That's a lot of power! I was a bit confused as to why this is happening, and internet searches turned up a few other people noticing the same, but little practical discussion about it, occasionally suggesting that PowerTOP is reading false results. I'm not so sure. From my light testing, the power drain is real, but fortunately it's not too hard to stop it.

    Assuming you're not actively using docker, and you'd like to keep your battery consumption down, you can just disable the interface. On my debian laptop, this is as simple as running /sbin/ifconfig docker0 down. The interface goes away, the system power drain drops accordingly, and so far, I seem to be getting ~20% or so better battery life for unplugged usage, although I have not yet run any formal benchmarks.

    What even is docker0?

    So what is this mystery power hog? It's an ethernet bridge device. Docker is using it to join it's virtual container networks to your computer's usual networks, so you can network between them and the 'real world'. My assumption is that in the default configuration it's causing the physical network adapter in my laptop (which I almost never use, but I presume is GigE), to be somehow 'live', and it's drawing power even though it's not transmitting or receiving any packets or connected up to any wiring. Looks like the bridge gets setup when docker is installed, and the device subsequently isn't ever set 'down' when it isn't running.

    I assume, like most docker things, the default networking setup is configured to be the most broadly useful and trouble free, and tweaking is reserved for the expert. I am fine with this. Broadly speaking this would seem to be the docker ethos, and it's got them a long way. It's always worth remembering that the 'docker magic' involves a whole bunch of things running below the abstractions, and if you use it a lot it's probably worth learning up on how it fits together to avoid being suprised.

    I don't actually use docker very much, but I occasionally run a couple of things that want it, and it's a useful tool to have in the toolbox. Accordingly I am running the version packaged with debian buster, which reports itself as version 18.09.1. I have done no particular further configuration of the networking or docker service.

    My LXC doesn't seem to have the same issue.

    I do use lxc/lxd a lot and I have a similar bridge device configured for my lxc containers to use. This does not seem to consume any particular power even when in use with containers running. I have been actively using LXC for years it's an essential part of my developer workflow (I use it to sandbox everything for reproducible builds or service testing, run database servers, etc.), so although I think I'm using the out-of-the-box packaged lxc-net service now, I have most certainly spent a lot of time carefully setting up my lxc-bridging by hand in the past, and I may have inherited some of that customisation through to the present day. I don't actually think this is true, but I mention it in the interest of full and fair disclosure.

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  2. 2018-12-06

    selfie time again

    Apparently, old people need to wear glasses.

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  3. 2018-09-06

    Autographed copy, sailors

    Burt Reynolds gone, at 82. One of the greats. He was everywhere when I was a kid, and I've unironically loved him ever since. The stars were so much brighter way back then. RIP

    Everyone's going to justifiably point out Smokey & the Bandit, the Cannonballs, and the critically accepted opinion is that his best moments were Boogie Nights and Deliverance. Hard to argue with that. Unquestionably underrated as an actor, there's more variety in his career than you'd think. Some of it deliciously weird. I maintain he's worth watching in anything but I'll highlight three of my own favourite moments that are laced with an edge of something a little off-piste. One great, one fan service, and one trainwreck.

    • The End : Burt directs, wherein he attempts a knockabout slapstick in which he plays a terminally ill man institutionalized after trying to commit suicide. Some days, I count this as my favourite movie. Has Sally Field, and Dom DeLuise to make up the seventies Burt holy trinity.

    • His X Files episode: Yup, that's right. Long after everyone had stopped watching the X-Files, he gets a custom-written episode. He plays God, against agent Doggett. Doggett knows underappreciated too.

    • Mad Dog Time: A movie so questionable, Roger Ebert gave it zero stars. I was lucky to catch this bomb on it's tiny cinema run, and I loved how incomprehensibly strange it was. Gangster satire? Spoof Noir? Situationist Prank? Yellowism? I was enthralled.
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  8. 2018-05-16

    This is my working from home face

    riffs, yeah

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  9. 2018-04-14

    If I was in charge at Netflix, I would shake up my reboot of Lost in Space by making it actually be a suprise reboot of "Lost", in space.

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  10. 2018-04-13

    Strong personal branding requires strong personal merchandising.

    I carry a badge

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  11. 2018-04-09

    New office, first day

    fancy shared workspace

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  14. 2018-03-29

    I am typing this onto a phone, on a station platform, squinting at the early morning light. It is damp on the ground. Many birds, still excited enough by the recent dawn, and cheered on by the imminent Spring, are loudly singing in their particular competitions.I have been awake since stupid o' clock. I am a commuter, I have a headache, and I have a back-ache, and I am tired.

    I have been doing this routine, or a near variation of it for the last seven or eight years. It's been very useful. I have been privileged enough to afford to maintain a whacking great family home, in a comfortable part of Kent, and shuttle back and forth to the big smoke, and taken my parts, minor and significant, in various start-up and scale-up companies, some doomed, some successful, almost all of them great fun, inside London's burgeoning 'tech scene'.

    As of today, I am done. Today is my last commute.

    Now on the train, speeding toward Cannon Street. By some miracle of kindness, this train, frequently delayed, often truncated, usually rammed to the gunwales with the pissed-off, the late, the drooling snorers, the dextrous make-up applicators, the slightly terrifying morning Stella drinkers, arrived on time, and half-empty, and I have a seat, with a half-table. Airline seating, but nobody is pinning me in with an arse much larger than the mean spirited seating budget. Somebody up there likes me.

    "When a man is tired of London, he's tired of life", as the hoary old paraphrased proverb would have it. I'm not tired of life. I don't even think I'm tired of London. I haven't finished exploring it yet. I would like to do a bit more life, and a bit less dull routine. Recently, it's all been feeling a bit repetitive, and formulaic, and stale, and not really me. It feels like the right time to make some changes.

    I suppose 2018 seems to be my year for quitting things, from the outside. Over here I'm less sure of that. Change can be healthy, and constructive. A chaos wizard binds disorder and fluid energies into tools of power, after all. I don't believe in mid-life crises. I do believe in making the most you can from out of what you have. That's how the magic works.

    We're bang in the middle of selling the house. Planning to move further out, to the coast. I shall miss London, but only in the way I missed it when I left before, twenty-five years ago, perhaps more. That was opening a chapter onto great and marvellous things. This time will also. I'm sure I will be back. Meanwhile, I'm saying goodbye, at least for now.

    Now just pulling in to London Bridge. I like the Shard. It wasn't even a thing when we first moved here. Scenes change, always. Exciting.

    Cannon Street. One last day in the office. That's the end of my first, and probably last, ever live-blogged commute. A great run. That could not have gone better. I call that a perfect ending.

    Laters!

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  15. 2018-03-24

    I stumbled across a reference to the RMS Mülheim, and ended up in a wiki-hole. This German cargo ship was wrecked at Land's End in 2003, in apparently bizarre circumstances.

    On investigation, it was discovered that the chief officer—who had been on watch at the time—had caught his trousers in the lever of his chair when trying to get up, causing him to fall and rendering him unconscious."

    This brings to mind those periodic surveys about accidents in the home, wherein you learn that something inauspicious, like the toothbrush, is a significant factor in a majority of domestic fatalities. When I looked into it a little more, I did notice that trousers are involved in a surprising number of domestic incidents. In this article from 2001, they get the blame for 6000 accidents a year.

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  17. 2018-03-06

    Project 'get off the main web and back onto the indieweb' has been a little bit derailed by 'life events', some of which I should probably blog more about, in the truest spirit of that community. I am still plugging away at it over here in the corner, quietly.

    /me waves

    In addition to refocusing on self-hosting, some of my other goals were to play better with the "fediverse", experiment with a couple of p2p alternative Internets, and do a few more real-life networking. So tonight there's an opportunity to combine a couple of those, as tonight I am attending the London Mastodon Meetup, in the guise of one of my many secret identities, '[email protected]'.

    I'm not sure that disappointed is quite the right word to use, but part of me thinks it's a shame that it isn't

    1. called a toot up
    2. happening in Tooting
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  18. 2018-03-06

    So far, the most personally visible effect of the upcoming UK GDPR data regulation is an uptick in "about GDPR" emails from financial orgs that all look a bit like phishing attempts :-/

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  19. 2018-03-05

    Happy 37th birthday, Sinclair ZX81!

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  20. 2018-03-04

    A few months ago, I hacked together a kano system to give the children an introduction to computers and what everyone seems to want to call 'coding'. I like the idea, and the style of the kano kit , but I was a little bit dubious about dropping a couple of hundred quid on a 'edutainment' project that might prove to be of little lasting interest. I'm not particularly hung up on the kids achieving productivity with the thing, but if I'm going to increase my pile of computery devices, I'd prefer to invest in things that are going to be useful.

    I hacked together my own Kano

    Like so many recent consumer 'DIY' hardware kits, the kano systems are built over the super-popular Raspberry Pi single board computer system. The nice kano people provide downloads for their base system (which is built over linux), as well as all their educational software. So, you can fairly cheaply assemble a scratch-build system from parts, especially if you have most of the parts already lying around in your gigantic pile of computery devices, which of course, I mostly do. You just need a screen, a Pi, some input devices, and a suitably-sized SD card to flash an OS image to. (Use this app!)

    It all works fairly well. They bundle a collection of educational free software, including the usual suspects (Sonic Pi, Scratch), some slightly more suprising and fun inclusions (Minecraft Pi Edition), and their own 'Kano Blocks' programming system, a kind of scratch-like skin over maybe Python and JavaScript (I haven't really looked into it too much). Most of the value add comes with the user interface kano have used to tie all this together - it's got a nice colourful simplified desktop, and an onboarding script that uses a charming story-telling metaphor with an unfolding narrative (that starts out in a UNIX shell!) to nudge you into a 'learn to program' RPG style adventure. This takes the form of a Zelda style game that walks you through various scripted programming assignments, with a kind of quest structure. The backstory is sort of an updated spin on 'little computer people'. Overall it's quirky, charming, and seems to be quite engaging. Certainly, more appealing and welcoming to younger children than something like a bare Raspbian desktop with the various apps installed.

    I think designing user interfaces is really hard. I've done a bit of it myself. To my mind, it is at least as hard, perhaps harder, than writing computer software. On this front, despite a few rough edges, I've been really impressed with how well the Kano design caters to it's audience. By and large, it's pretty suitable for reading-age children to work with mostly unsupervised. (Pleasingly, there's no requirement for a network connection). That's quite a feat. It's not iPad-easy, but it's offering a significantly more freestyle, open-ended computer experience. I had a tiny bit of troubleshooting with WiFi drivers, and sound initially (hey, it's linux on the desktop after all). I expect these wouldn't present if you were using the official hardware kit. I would give a gentle recommendation of kano to anyone that was thinking of introducing a 6-8 year old child to 'computing' in a useful sense. Most of our interface struggles came from a less expected direction...

    Intuition

    Kano uses a tradtional desktop metaphor, which expects you to have a keyboard and a mouse/trackpad. It's straightforward adding these to a Pi. You can use any standard keyboard or mouse. Your options are USB type A, or Bluetooth. As you might expect, I have piles of these lying around. As it turns out, mostly these are Apple devices, because of historical reasons. These seem ideal. Apple! The fêted industrial design company. Really well built, attractive equipment. Attractive. Robust. World-beating, reliable Bluetooth stack. I had a small parts bin to choose from. Wireless and wired. Mice and trackpads. Aluminium and polycarbonate.

    They kind of worked as well as you'd expect. Except the children found them too confusing to use. It turns out, they're riddled with implied behaviour. Multitouch click behaviour for left and right clicks. Or completely invisible mouse 'buttons'. Weird icons for SHIFT, and TAB, and ENTER, and CAPS that are mostly subtle variations on the same symbol. Granted, I'm using the devices outside their expected context, but I was struck by the irony of how unintuitive all of this was, and also how unneccessary. I can appreciate that there's an aesthetic at play here. From a decorative perspective, there's a tasteful and consistent minimalism that ties it all together. I don't think it exhibits good design. I think it's just pseudy, pretentious, and fake.

    I like things to be pretty, and I value design. Both concepts are linked, but they ain't the same thing. Minimal interface design is a laudable goal. If you remove complexity from the interface medium, you remove boundaries, lower overheads, and make a system that's quicker, effective, and less taxing to use. If you do this, and you succeed in doing it well enough, there's an inherent beauty to any well considered tool, that sits somewhere beyond visual proportionality and materials. All these Apple peripherals fail to deliver much of this, sometimes quite badly. I was a bit surpised that I never noticed this so directly in the ten years or so I worked with these tools. But I was already an expert user, these flaws were a couple of layers lower than I was used to looking. Admittedly, some of the mice were pretty terrible, but I have famously always been more of a keyboard man.

    After a couple of months of rotating the devices, and patiently explaining that you press over here for this kind of click with this finger, and over there for the other purpose, with a different finger, and this kind of arrow is SHIFT, but that kind of arrow is CAPS LOCK, and scrolling happens this way, I caved and bought a Logitech K-400. It is battleship grey, and not particularly pretty. It uses a dongle for wireless, not bluetooth. The integrated touchpad works fine, and has two differentiated physical buttons. The SHIFT key is labelled with the word 'Shift'. It has been immediately popular, and I have not yet had to field a single question about how the keyboard or pointer works.

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