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Joined 1 year ago
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Cake day: June 14th, 2023

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  • emerges from a brand you’ve probably never heard of

    Writing this on a Tuxedo Pulse 14 / gen 3 as we speak. Great little laptop. I’d wanted something with a few more pixels than my previous machine, and there’s a massive jump from bog-standard 1080p to extremely expensive 4K screens. Three megapixel screen at a premium-but-not-insane price, compiles code like a champion, makes an extremely competent job of 3D gaming, came with Linux and runs it all perfectly.

    “Tuxedo Linux”, which is their in-house distro, is Ubuntu + KDE Plasma. Seemed absolutely fine, although I replaced it with Arch btw since that’s more my style. Presumably they’re using Debian for the ARM support on this new one? This one runs pretty cold most of the time, but you definitely know that you’ve got a 54W processor in a very thin mobile device when you try eg. playing simulation games - it gets a bit warm on the knees. “Not x64” would be a deal-breaker for my work, but for most uses the added battery life would be more valuable than the inconvenience.




  • One of the things that got me to change my gaming desktop from Mint to Arch was the fact that you get the cutting-edge version of everything; kernel and amdgpu being the most important, but also getting the latest version of Lutris and things is nice too. Brought me from “usually about 50 fps outdoors in Elden Ring” to “usually about 60 fps” on the same machine.

    Makes sense for a gaming machine to only include the services you actually want, which Arch enables. Supports my hardware better too - my audio gear works perfectly in Pipewire but is ropey in ALSA, so rather than “install Mint -> install Pipewire -> remove ALSA -> hope ALSA is gone”, the sequence is “install Arch -> install Pipewire”, which make more sense.

    Other cutting-edge rolling release distros are available, of course, but once you learn Arch, it makes a lot of sense for gaming.


  • Yeah.

    There’s a couple of ways of looking at it; general purpose computers generally implement ‘soft’ real time functionality. It’s usually a requirement for music and video production; if you want to keep to a steady 60fps, then you need to update the screen and the audio buffer absolutely every 16 ms. To achieve that, the AV thread runs at a higher priority than any other thread. The real-time scheduler doesn’t let a lower-priority thread run until every higher-priority thread is finished. Normally that means worse performance overall, and in some cases can softlock the system - if the AV thread gets stuck in a loop, your computer won’t even respond to keyboard input.

    Soft real-time is appropriate for when no-one will die if a timeslot is missed. A video stutter won’t kill you. Hard real-time is for things like industrial control. If the anti-lock breaks in your car are meant to evaluate your wheels one hundred times a second, then taking 11 ms to evaluate that is a complete system failure, even if the answer is correct. Note that it doesn’t matter if it gets the right answer in 1 ms or 9 ms, as long as it never ever takes more than 10. Hard real-time performance does not mean good performance, it means predictable performance.

    When we program up PLCs in industrial settings, for our ‘critical sections’, we’ll processor interrupts, so that we know our code will absolutely run in time. We use specialised languages as well - no loops, no recursion - that don’t let you do things that can’t be checked for an upper time bound. Lots of finite state machines! But when we’re done, we know that we’ve got code that won’t miss a time slot in the next twenty years of operation.

    That does mean, ironically, that my old Amiga was a better music computer than my current desktop, despite being millions of times less powerful. OctaMED could take over the whole CPU whenever it liked. Whereas a modern desktop might always have to respond to a USB device or a hard drive, leading to a potential stutter at any time. Tiny probability, but not an acceptable one.


  • They’re bullshit generators, essentially - it doesn’t matter to them whether they generate something that’s ‘true’ or not, as long as it’s plausible. Depends what you intend to use them for - if you want a throw-away image for a powerpoint slide that will only be looked at once for a few seconds, they’re ideal. They generate shit code and boring, pointless stories, so couldn’t recommend them for that.

    If you’re a D&D GM that’s in need of quite a lot of ‘disposable’ material, they’re alright. Image of a bad guy that you can then work into the story? Great. Names for every single Gnomish villager? Great. Creating intricate and interesting lore that brings your world alive? No, they are not actually intelligent and cannot do that - that’s the part that you provide.

    At the moment, huge amounts of venture capitalist money is making these things much cheaper than their true cost. Can only imagine the price of them is going to go up a lot when that runs out. You might not be able to afford the subscription, but you’ll be in good company soon.




  • I used to work with a Greek guy called Argyros Argyros - cool guy, but suspect he was an outlier. Named after his dad, so certainly some people are named that way. Icelandic for instance would traditionally use “Given Name” “Patronym from father” - Magnus Magnusson was quite famous in the UK; Björk Guðmundsdóttir might be the most famous internationally, but she’s not a “double”. There’s quite a few cultures - Hungarian, Chinese, Japanese, … - that write their names as “Family Name” “Given Name” as opposed to the other way around, if that’s what you mean?







  • Can confirm that this does work perfectly for Lutris, for upgrades at least. I’ve got my home directory on an NVMe drive and my games installed on a slower disk; as long as you don’t move or rename any of the partitions, it just keeps rocking along.

    My laptop and desktop have a different list of games installed, but because Lutris uses SQLite as its backing store, it’s not terribly easy to keep ‘some parts’ synchronised and others not. I’ve spent a bit of time getting all of the icons, banners, release dates, etc all correct and looking pretty, and it’s a shame that it’s tough to reuse. (Lutris does this automatically for Wine installs if you get the name ‘just right’ to start with, but not for all your other emulated stuff - all the DOS games and things.)


  • Not all of the light would have been wasted on the wall. If your wall is painted green, then the ‘rest of the rainbow’ (red, orange, yellow, blue, violet wavelengths) would be absorbed and converted into heat. Paint is quite rough on a microscopic level, and the green light reflected would be scattered in every direction.

    Things that have a colour do so because they reflect those frequencies. Mirrors reflect pretty much all frequencies of visible light with very little scattering - that’s the definition of the word, really.

    If you had a black feature wall behind your lamp, such that very little was reflected off it into the rest of the room, then with a mirror there would be about twice the photons illuminating the room. If your wall was pure brilliant white, much less of a difference. Your eyes don’t perceive ‘twice the photons’ as ‘twice as bright’ - they scale from absorbing thousands a second when fully dark-adjusted at night, to trillions per second at midday - but you might find it a bit easier to eg. read a book elsewhere in the room.

    Light output from the lamp doesn’t change, but depending on the colours of things in your room, the light output that is useful for seeing might do.


  • Really? If it’s a big enough treatment works to warrant a SCADA, then I doubt an automation engineer with the experience to set it all up would be asking this question, but here goes. You’ve a couple of obstacles:

    • every contract I’ve ever seen for industrial automation has either specified which control plane they want directly, or they’ll have a list of approved suppliers which you must use. Someone after you will have to maintain this. Those maintainers will only accept the things that they have been trained on. Those things are Windows PCs running Windows software. They will reject anything else. The people running network security on those machines will have a very short list of the acceptable operating systems for running SCADA systems. That list will be a couple of versions of Windows Server. They will also reject anything else.

    • that’s not nearly enough information to make a recommendation. Which PLCs? Allen Bradley, Siemens, Mitsubishi, …? I can’t think of a job I’ve ever been on where the local HMI hasn’t matched the PLCs. The SCADA software almost invariably matches the PLCs used in the main motor control centre, with perhaps a couple of oddball PLCs for proprietary panels and such like. Could maybe ask the supplier if they’ve a Linux alternative? Siemens will laugh at you and Mitsi won’t understand the question, but AB just might.

    Sorry - I’m a Linux evangelist, but I don’t think it’s a good fit for here. SCADA performance generally isn’t bad due to Windows Server - it’s fine, does what it’s intended to - but because eg. STEP 7 is an appallingly slow and bloated piece of software which would bring a mainframe to its knees. Which is bizarre - the over-the-wire protocol connecting the machines is generally a short binary blob described in the PLC configuration - these bits are the drive statuses, these bits are an int or a float for an instrument readout - and it shouldn’t be at all slow updating it all, but slow it is.