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Cake day: July 8th, 2023

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  • This is madness, but since this is a hobby project and not a production server, there is a way:

    • Shrink the filesystems on the existing disks to free up as much space as possible, and shrink their partitions.
    • Add a new partition to each of the three disks, and make a RAID5 volume from those partitions.
    • Move as many files as possible to the new RAID5 volume to free up space in the old filesystems.
    • Shrink the old filesystems/partitions again.
    • Expand each RAID component partition one at a time by removing it from the array, resizing it into the empty space, and re-adding it to the array, giving plenty of time for the array to rebuild.
    • Move files, shrink the old partitions, and expand the new array partitions as many times as needed until all the files are moved.

    This could take several days to accomplish, because of the RAID5 rebuild times. The less free space, the more iterations and the longer it will take.




  • I do tend to think of choices that way. The way I understand the human mind is as a rational optimizer of utility. The brain has to balance all manner of competing sensory and cognitive input, and the mind constantly seeks to maximize pleasure and/or relief from distress. (That’s what I mean by utility.) They say that all models are wrong, but some are useful, and this one proves very useful. Instead of dismissing people as disturbed or crazy, look for the pleasure or relief that their mind is optimizing for. Drug users destroying their lives by seeking the next fix do so because the pleasure and relief of the drug is greater than distress from alienating family and friends. This is why people have to hit rock bottom before they’ll kick the addition; it’s when the distress of ruining their lives overwhelms the lure of the drug. This model even helped me understand a friend with schizophrenia. Her decisions were quite rational, actually, but were based on distorted and false perceptions.

    Now this is funny, writing it out like this brought a mini-epiphany to me, a different model of what “free will” might mean. Our minds do have the freedom to change and react differently to different sensory and cognitive inputs. We’re not automatons fixed to a preset course of action. And it makes sense that way that even protozoans have some degree of free will. Intriguing!


  • I think about this a lot, about free will to make a choice in an otherwise-deterministic universe, and the thing that gets me is… yeah, it sort of makes sense if you consider the person making the decision like a black box. A decision comes out, and it seems free.

    But what goes on in the box? How can it possibly be free will? If I were making a choice to benefit myself, and I had perfect information about the options and the consequences, then wouldn’t everybody in my position make the same (objectively best) choice? If I make a non-optimal decision because I lack some information, then that’s not free will, that’s due to an external circumstance. If I make a non-optimal decision because I’m not of rational mind, then that’s not free will, that’s either an intrinsic quality of my mind, or due to external influences. If I chose to be intentionally non-rational to prove that I have free will, the idea of free will itself and the need to prove it would be the external influence driving me.

    If the choice was just one of just one of preference, then the preference is either one I was born with, or the product of outside influences. Maybe there’s somebody who can logic themselves into liking cauliflower au gratin without reference to subjective sensory experience, or cultural significance, and I just can’t imagine how?





  • Every food label, with very few exceptions, lists the contents in either grams or milliliters, in addition to ounces or fluid ounces. Every thermometer I’ve ever seen has both Fahrenheit and Celsius scales. We buy electricity in watts with metric currency. We measure the light output in lumens, and the common lightbulb sizes are measured in millimeters, but the wires that carry the electricity are measured by AWG. The parts on my bicycle and car all use metric measurements, except for tires. Tires are an unholy abomination with section width given in millimeters, the cross-section in a unitless ratio, and the rim diameter given in inches.

    Meh, what’re you gonna do? We switched to, or adopted, SI and metric where it made sense, but we have a lot of legacy systems.



  • You’re really missing out! In my opinion, PBR is the best of the “cheap and shitty” tier of mass-produced beer that rednecks and poor college students drink to get smashed. It’s not good, exactly, but somehow nostalgic to me for drinking around a campfire. The U.S. has plenty of mass-produced beer that’s still mediocre, but better than PBR, and some that’s even pretty decent. It’s in the craft breweries that you’ll find the really great American beer, though.


  • Oh, hey, Jerboa is not so good about updating the Inbox tally…

    I was responding to your question about kW per hour, and I was going for the intuitive sense of why that’s not right. The more “it’s just so” reason is that the math just doesn’t work, since the word “per” signifies division. So if we discharge a battery at a rate of 100 watts for 3 hours, that’s 100W * 3 hours, or 300 Wh used. If we say 100 watts per hour for three hours, that’s 100W / 1 hour * 3 hours. The hours cancel, and the result is 300 watts, which is a rate.

    It’s totally confusing, I know, because people often use “watts” and “watt-hours” interchangeably, but they’re as different as speed and position.

    Anyway, the watt is a derived unit in SI, and it’s equivalent to kg·m2 / s3. The per-unit-time is hidden when you write it as a watt, but clearly there when you write it in terms of base units. Of course, the joule is kg·m2 / s2, so energy also has time in the denominator, and I guess could technically also be a rate, but understanding that is way above my pay grade. 😀




  • The 5¼" floppy disks consisted of the floppy disk coated in magnetic substrate, encased a plastic envelope. The drive mechanism would only have one read/write head, to read one side of the disk. Disk manufacturers would sell single-sided floppy disks, as well as double-sided floppy disks that you could physically flip over to store more data on the other side. The double-sided floppy disks were a lot more expensive. The only real difference between the two types, though, was that the manufacturers warrantied that the second side would work; to save production costs, the disks were otherwise mostly the same.

    The drives had a simple, mechanical write-protect sensor. If the edges of the plastic envelope were intact, putting a disk in the drive would block the sensor, and the drive wouldn’t allow writes. But, if there were a small notch cut in the edge, aligned with the sensor, the disk would not trigger the write-protect mode, and you could write to the disk.

    The single-sided disks had a notch cut in one edge of the envelope to allow writing to one side of the disk. But, if you cut a notch in the same spot on the opposite side of the envelope, you could disable write-protect mode on the flip side of the disk. A hole punch was the easiest way to make the notch. Voilà! You could store twice as much data on the same disk.


  • A watt is a derived unit for a rate of change, an amount of energy used in a unit of time, so P = E / t. A kW per hour would be a rate divided by time, or E / t^2, resulting in another rate.

    More colloquially, think of watts/power by analogy to another rate, that of speed. Moving at a speed of 100kph for 3 hours results in 300 speed-hours of distance. Saying 100 kilometers per hour per 3 hours sounds awkward, but is actually a weird way to say acceleration, a rate of change of speed. (And probably a hint to get your car serviced.)

    Anyway, the key is to think of a kilowatt as a rate, not a quantity.



  • I don’t know about theory, but the big practical advantage to ZigBee is that it works.

    Sorry, that’s a shitty thing to say. I’m salty because the only time I tried X10 was 25 years ago, and the experience was less than great. Unreliable switching, spurious commands, slow performance, etc. Sending signals over the power wires sounds great in theory, but in practice there are all sorts of pitfalls, like resistive versus inductive loads, bridging circuits to different legs of two-phase power, or conflicting commands on the wire.

    ZigBee has just worked for me, since it avoids all of the potential wiring issues. You just plug a device in, put it in pairing mode, and Home Assistant finds it, interrogates its capabilities, and adds it (by name) with the correct entities. No mucking about with addresses, or adding signal paths to the house wiring. As a mesh network, it’s quite robust, since most plugged-in devices act as repeaters.

    The downside of ZigBee, of course, is that it may not work well in WiFi-saturated environments, since it uses the same 2.4GHz frequency band.



  • For troubleshooting, start at the destination and work back. Run a packet trace on the target machine, and other machines on the WiFi network to see if any WoL packet comes through at all. If not, then look at the VM host.

    How does HAOS access the USB network adapter? By pass-thru, so it’s like a USB device connected to the VM, or through a bridge on the VM host? If it’s the latter, a Linux network bridge device is often configured not to pass broadcast packets by the firewall rules. (Things like Docker will enable firewall filtering.) Check that the bridge allows broadcast packets through. If it’s the former, the USB pass-thru, do a packet trace from HAOS to ensure that it’s actually sending the packet, I guess.