Off-and-on trying out an account over at @tal@oleo.cafe due to scraping bots bogging down lemmy.today to the point of near-unusability.

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Cake day: October 4th, 2023

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  • I don’t know about the Mac Bluetooth stack, but if these machines are both network-connected and active simultaneously, there’s software that will let one proxy to another over the network. In that scenario, you have the associated software installed on both machines, your keyboard/mouse/whatever connected to one machine, and then hit a key combination or similar to switch, which should be effectively instantaneous.

    searches

    It sounds like it’s called a “software KVM” or a “virtual KVM”. I won’t try to recommend one, as I haven’t used any, but it might be a way to avoid the delay that would work for you. One example, though:

    https://symless.com/synergy




  • I’m not particularly enamored of publicly-owned utilities, but one data point in their favor — Santa Clara uses their own power utility, and their rates are considerably lower than PG&E’s.

    https://en.wikipedia.org/wiki/Silicon_Valley_Power

    Silicon Valley Power (SVP) is a not-for-profit municipal electric utility owned and operated by the City of Santa Clara, California, United States. SVP provides electricity service to approximately 55,116 residential and business customers, including large corporations such as Intel, Applied Materials, Owens Corning and NVIDIA. SVP also owns and maintains a dark fiber network named SVP Fiber Enterprise.

    searches

    Well, this is SVP’s site, so not really an objective source, but I think it makes the point, and I’ve read about it elsewhere.

    https://www.siliconvalleypower.com/residents/rates-and-fees

    SVP D-1 average residential rate is $0.182/kWh.

    PG&E E-1 average residential rate is $0.422/kWh.

    $.18/kWh isn’t amazing by US standards, but it’s much closer to typical US rates than California as a whole is.




  • One of them, a top military officer, said the idea was to ensure that whoever was in the role had sufficient experience that they would be respected if they tried to push back on controversial National Rally proposals — including leaving NATO’s integrated command.

    I mean, I personally don’t think that that would be a great idea for France, but France already spent decades as a NATO member but outside NATO’s integrated command, and if it does so again, it’s probably not going to end the world.

    https://en.wikipedia.org/wiki/France_and_NATO

    In 1966, under De Gaulle’s leadership, France withdrew from NATO’s integrated military command. Nevertheless, cooperation agreements between French and NATO forces were quickly signed, reducing the practical impact of this withdrawal. This cooperation was reinforced under Presidents François Mitterrand and Jacques Chirac, and in 2009, President Nicolas Sarkozy reinstated France into NATO’s unified command.




  • Is this worth the effort?

    In terms of electricity cost?

    I wouldn’t do it myself.

    If you want to know whether it’s going to save money, you want to see how much power it uses — you can use a wattmeter, or look up the maximum amount on the device ratings to get an upper end. Look up how much you’re paying per kWh in electricity. Price the hardware. Put a price on your labor. Then you can get an estimate.

    My guess, without having any of those numbers, is that it probably isn’t.





  • Another thing to note about gaming keyboards is that they often advertise “n-key rollover” (the ability to have n simulataneous keys pressed at once — for many key combinations, typical keyboards will often only let you press two keys at once, excluding modifier keys). Although not generally tested here, I tried a “Razer DeathStalker Expert Gaming Keyboard” that advertises “Anti-ghosting capability for up to 10 simultaneous key presses”. The Razer gaming keyboard did not have this capability in a useful manner and many combinations of three keys didn’t work. Their advertising claim could, I suppose, technically true in that 3 in some cases could be “up to 10”, but like gaming keyboards claiming to have lower latency due to 1000 Hz polling, the claim is highly misleading at best.

    That being said, the real issue was keyboards that used matrix encoders, where all keys were represented in a matrix, addressed by one line going high on the X axis and one line going high on the Y axis. I understand that this is cheaper, and expect that it’s probably because this requires running fewer traces from the keys to the controller than doing one for each. It looks Something like:

    - X1 X2 X3
    Y1 “Q” “W” “E”
    Y2 “R” “T” “Y”
    Y3 “U” “I” “O”

    That’s just a 3x3 matrix, as an example. So if I press “Q” on my keyboard, the X1 and Y1 line will go high. If I keep it pressed and then additionally press the “W” key, the Y1 line, which is already high, will stay high. The X2 line will then also go high. The controller can detect the keypress, since a new line has gone high.

    If I keep both keys pressed and then additionally press the “R” key, then the X1 line is already high due to the “Q” key being down, and will stay high. The “Y2” line will go high. The controller can detect the keypress.

    However, if I then press the “T” key, it can’t be detected. Pressing it would normally send the X2 line and Y2 line high, but both are already high due to existing keys being pressed.

    In practice, keyboard manufacturers try to lay out their matrix to try to minimize these collisions, but there’s only so much they can do with a matrix encoder. They’ll also normally run independent lines for modifier keys.

    A controller using a matrix encoding can always detect at least two keys being simultaneously pressed, but may not be able to detect a third.

    Matrix encoders aren’t really an issue when typing, but some games do require you to press more than two non-modifier keys at once. For example, it’s common to use the “WASD” keys for movement, and moving diagonal requires holding two of those. if someone is playing a game that requires pressing another key or two at once, those might collide.

    As I recall, USB sends the full state of the keyboard, not events specific to a button when a button is pressed. There are protocol-level restrictions on the number of “pressed keys” that can be pushed. That means that USB keyboards don’t support n-key rollover, and are why you’ll see some companies selling gaming keyboards with a PS/2 option — because that protocol does send state on a per-button basis. (It’s also why, for those of us that have used PS/2 keyboards and have experienced this, it’s possible to get a key on a PS/2 keyboard “stuck” down until it’s pressed again if the OS, for whatever reason, misses a key-up event.) USB gaming keyboards probably (hopefully) won’t actually advertise n-key rollover. But they can avoid using a matrix encoder, and in general, one really doesn’t need n-key rollover for playing games — just the ability to detect up to the USB limit. We only have ten fingers, and I don’t think that there are any games that require even something like six keys to be down at once.

    Obviously, in the case the author hit with the Razer keyboard, it wasn’t able to do that. I’m not sure what they’re doing (unless they’re simply completely fabricating their feature claim, which I assume that they wouldn’t). They might be using a larger matrix and sparsely-populating it, though I’m guessing there.


  • You can definitely feel 100 ms in input response time. That’s about what an analog modem’s latency would be. I can tell you, that’s very much noticeable on a telnet or ssh connection when you’re typing (though to be fair, what matters there is really round-trip time, so one should probably double that).

    On that note, if someone hasn’t run into it, mosh uses UDP and adaptive local echo to shave down network latency for terminal connections, and might be worth looking into if you often do remote work in a terminal over a WAN. It uses ssh to bootstrap auth (if you’re concerned about using less-widely-used thing what does network authentication, which I remember I was). I find that it makes things more pleasant, and also like some of its other features, like auto-reconnecting after an arbitrary length of time. One can just close a laptop and then reopen it a week later and the terminals function. Tmux and GNU screen can also do something similar — and in fact, I think that mosh and tmux are good packages to pair with each other — but they don’t do quite the same thing, as they require (a) manual re-establishment of connection and are (b) aimed at letting one reconnect from different clients. It also displays a notice in the terminal if there’s temporary network unavailability until it’s re-established communication, so the user isn’t simply staring at his screen wondering whether the software on the remote machine is being unresponsive or whether it’s a network issue.


  • tal@lemmy.todaytoProgramming@programming.devKeyboard latency
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    3 days ago

    That’s…actually a substantial amount more latency than I’d expected. Not exactly the same thing, but for perspective, while I haven’t played multiplayer competitive FPSes for many years, back when I did, the limit of what I could really “feel” when it came to network latency was around 10 milliseconds. The latency the keyboards are adding, if it’s as high as measured, is a really substantial amount of delay to be adding if you’re talking video games.

    considers

    Note that depending upon the keyswitch mechanism, the controller does need to debounce the thing to avoid duplicate keypresses. I’ve used a keyboard before with a controller that didn’t adequately debounce, and it was extremely obnoxious — occasionally would get duplicate keypresses, and I had to filter it out at the level of my computer.

    However, if you look at gamepad button latency, they also need to worry about bounce, and their latency is much lower:

    https://gamepadla.com/

    You can get gamepads with sub-2-millisecond latency on USB.

    EDIT: Note that one thing that I learned from following !ergomechkeyboards@lemmy.world is that there are some semi-standardized open-source firmwares for (fancy, expensive) microcontroller-based keyboards; I believe that QMK is popular. I don’t know how the latency on those microcontroller-based keyboards compare, but assuming that there aren’t any fundamental constraints imposed by the other hardware on the keyboard, it might be possible to shave some time off of that by tweaking the firmware.

    I believe that at least some keyswitch mechanisms become more prone to bouncing over time, but if so, it might be possible for a microcontroller to detect bounces and tune the wait time to the mechanism on a given keyboard to adapt to mechanism wear.


  • New, Subscribed

    New: There’s a limited enough amount of content presently being submitted in the areas that I’m interested in that I don’t feel the need to try to use votes to filter out things. It’s not impossible that I’d move to something that accounts for votes in the long run, but it’s not enough of a torrent yet.

    Subscribed: I don’t believe that trying to view All and then blacklisting everything that you don’t want scales well. People can add communities all the time, and inevitably — there’s a huge amount of stuff out there — a lot of it isn’t stuff that I’m going to be interested in. It’s like trying to blacklist the Internet — means a constant game of whack-a-mole. Also, “All” will only see communities that are either local to your home instance or where another user on your home instance has already subscribed to things, so especially on smaller instances, you may never see something that you’re interested in that someone does create. I follow !newcommunities@lemmy.world, !communitypromo@lemmy.ca and hit https://lemmyverse.net/communities occasionally to find new communities of interest.