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Joined 2 years ago
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Cake day: February 1st, 2024

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  • Coming from Debian, it was…not expected. I understand how and why it happened, but the user experience was surprising.

    Debian keeps the previous kernel around, which makes perfect sense to me — in the event that a kernel update borks your system you can just load the previous one. This would probably only happen due to out of tree modules (looking at you, Nvidia…).


  • Coming from Debian, it was…not expected. I understand how and why it happened, but the user experience was surprising.

    Debian keeps the previous kernel around, which makes perfect sense to me — in the event that a kernel update borks your system you can just load the previous one. This would probably only happen due to out of tree modules (looking at you, Nvidia…).


  • qjkxbmwvz@startrek.websitetolinuxmemes@lemmy.worldWinblows
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    18 days ago

    Linux distros can still do…questionable things. In grad school I tried Arch for a bit, and I once was late to a video call because I had updated my kernel but did not reboot. Arch decided that because there was a new kernel installed, I didn’t need the modules for the old — but currently running! — kernel, so it removed them. So when I plugged in a webcam, the webcam module was nowhere to be found.

    But yeah…somehow, still not as bad as Windows updates.


  • Our Internet went out for a few hours today, so naturally my smart switches, lights, cameras, motion sensors, door sensors, and power monitoring… continued to work as of nothing was wrong.

    Home Assistant is great, and using local-only devices is awesome. If my smart home stops working it’s my own fault, not some 3rd party.



  • Aluminum foil is very common in physics labs. And a main use for it is “baking”! To get ultra high vacuum (UHV)* you generally need to “bake out” your chamber while you pump down. Foil is used same as with baking food — keep the heat in and evenly distributed on the chamber.

    Sadly, it’s usually not food grade aluminum foil, as that can contain oils, and oils and vacuum are generally a big no-no.

    *Just how good is UHV? Roughly: I live in San Francisco, which is ~7 miles by ~7 miles (~11km). Imagine you raise that by another 7 miles to make a cube. Now, evacuate every last molecule of gas out of it. Now take a family sedan’s trunk, fill it with 1 atmosphere of gas, and release that into the 7 mile cube. That’s roughly UHV pressure.





  • That’s…not really a cogent argument.

    Satellites connect to ground using radio/microwave (or even laser), all of which are electromagnetic radiation and travel at the speed of light (in vacuum).

    Light in a fiber travels much more slowly than in vacuum — light in fiber travels at around 67% the speed of light in vacuum (depends on the fiber). In contrast, signals through cat7 twisted pair (Ethernet) can be north of 75%, and coaxial cable can be north of 80% (even higher for air dielectric). Note that these are all carrying electromagnetic waves, they’re just a) not in free space and b) generally not optical frequency, so we don’t call them light, but they are still governed by the same equations and limitations.

    If you want to get signals from point A to point B fastest (lowest latency), you don’t use fiber, you probably use microwaves: https://arstechnica.com/information-technology/2016/11/private-microwave-networks-financial-hft/

    Finally, the reason fiber is so good is complicated, but has to do with the fact that “physics bandwidth” tends to care about fractional bandwidth (“delta frequency divided by frequency”), whereas “information bandwidth” cares about absolute bandwidth (“delta frequency”), all else being equal (looking at you, SNR). Fiber uses optical frequencies, which can be hundreds of THz — so a tiny fractional bandwidth is a huge absolute bandwidth.









  • I feel old…when I was learning how to run Linux I started with an old 386 (maybe 486?) my dad wasn’t using. I think it had 32MB RAM, which was fancy for those machines.

    We had dial up at the time, so only one machine could be on the Internet. So, I set up a modem on the x86, plugged into an Ethernet hub (switch?), and learned enough ipchains (this was before iptables) to share a connection. It also ran Samba, an AFP server, and probably FTP and HTTP (just for local access) — but it worked for filesharing.

    It could also run MP3 streaming software which amused me because the machine itself was too slow to decode MP3 (but that’s not necessary to stream).