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

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  • Especially after adding in all the power draw of the automation requires…

    What exactly is the incremental power draw for automation? My network gear and server (a little nuc) are sunk power costs as I self host other services.

    Idling, my home uses around 100W with the fridge off. One 10W light is an additional 10% of my power budget, and I have a lot more than one light in my house. I also pay about $0.40/kWh.


  • I can be a bit neurotic about turning off lights when I leave a room, so Home Assistant was a nice way to free up brain space for me. A few motion sensors here and there + some simple automations, and the lights mostly handle themselves. Zigbee sensors and Zigbee or Matter-over-WiFi bulbs, so everything is local. A free VPS+WireGuard setup means I can access them remotely should I need to, with TailScale as a backup.

    Cloud failures mean I can’t access remotely, but local control is unaffected—if my smart devices stop working it’s almost certainly my fault :)









  • It’s interesting that, with Python, the reference implementation is the implementation — yeah there’s Jython but really, Python means both the language and a particular interpreter.

    Many compiled languages aren’t this way at all — C compilers come from Intel, Microsoft, GNU, LLVM, among others. And even some scripting languages have this diversity — there are multiple JavaScript implementations, for example, and JS is…weird, yes, but afaik can be faster than Python in many cases.

    I don’t know what my point is exactly, but Python a) is sloooow, and b) doesn’t really have competition of interpreters. Which is interesting, at least, to me.







  • 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.