I have to admit - I still grind my teeth every time I see "dns propagation" used without a direct follow-up that it's a myth, you're looking at cascading cache expiry.
Propagation might be a useful way to visualise it, but doesn't match reality unless every cache is a warm cache.
DNS changes propagate. They just do-so in a pull, not push, way.
It’s accurate to say that a user is waiting for the change to propagate if they are sitting there clicking re-try as they wait for the cascading cache expirations to do their thing.
Yes! The idea of DNS records "propagating" gave me entirely the wrong mental model of DNS very early in my career. Granted, the confusion didn't last long because I read the cricket book soon after, but it was still pretty jarring.
Compelled speech is protected, fingerprints aren't.
Imagine it's 1926 and none of this tech is an issue yet. The police can fingerprint and photograph you at intake, they can't compel speech or violate the 5th.
That's exactly what's being applied here. It's not that the police can do more or less than they could in 1926, it's that your biometrics can do more than they did in 1926. They're just fingerprinting you / photographing you .. using your phone.
> with the context mostly being HDD manufacturers who want to inflate their drive sizes
This is a myth. The first IBM harddrive was 5,000,000 characters in 1956 - before bytes were even common usage. Drives have always been base10, it's not a conspiracy.
Drives are base10, lines are base10, clocks are base10, pretty much everything but RAM is base10. Base2 is the exception, not the rule.
It goes back way further than that. The first IBM harddrive was the IBM 350 for the IBM 305 RAMDAC. It was 5 million characters. Not bytes, bytes weren't "a thing" yet. 5,000,000 characters. The very first harddrive was base-10.
Here's my theory. In the beginning, everything was base10. Because humans.
Binary addressing made sense for RAM. Especially since it makes decoding address lines into chip selects (or slabs of core, or whatever) a piece of cake, having chips be a round number in binary made life easier for everyone.
Then early DOS systems (CP/M comes to mind particularly) mapped disk sectors to RAM regions, so to enable this shortcut, disk sectors became RAM-shaped. The 512-byte sector was born. File sizes can be written in bytes, but what actually matters is how many sectors they take up. So file sizing inherited this shortcut.
But these shortcuts never affected "real computers", only the hamstrung crap people were running at home.
So today we have multiple ecosystems. Some born out of real computers, some with a heavy DOS inheritance. Some of us were taught DOS's limitations as truth, and some of us weren't.
However it doesn't seem to be divided into sectors at all, more like each track is like a loop of magnetic tape. In that context it makes a bit more sense to use decimal units, measuring in bits per second like for serial comms.
Or maybe there were some extra characters used for ECC? 5 million / 100 / 100 = 500 characters per track, leaves 72 bits over for that purpose if the actual size was 512.
First floppy disks - also from IBM - had 128-byte sectors. IIRC, it was chosen because it was the smallest power of two that could store an 80-column line of text (made standard by IBM punched cards).
Disk controllers need to know how many bytes to read for each sector, and the easiest way to do this is by detecting overflow of an n-bit counter. Comparing with 80 or 100 would take more circuitry.
Almost all computers have used power-of-2 sized sectors. The alternative would involve wasted bits (e.g. you can't store as much information in 256 1000-byte units as 256 1024-byte units, so you lose address space) or have to write multiplies and divides and modulos in filesystem code running on machines that don't have opcodes for any of those.
You can get away with those on machines with 64 bit address spaces and TFLOPs of math capacity. You can't on anything older or smaller.
They almost always mean power of 10, unless you're discussing RAM, RAM addressing, or RAM pages. (or flash, which has inherited most of the same for most of the same reasons)
RAM had binary sizing for perfectly practical reasons. Nothing else did (until SSDs inherited RAM's architecture).
We apply it to all the wrong things mostly because the first home computers had nothing but RAM, so binary sizing was the only explanation that was ever needed. And 50 years later we're sticking to that story.
RAM having binary sizing is a perfectly good reason for hard drives having binary sized sectors (more efficient swap, memory maps, etc), which in turn justifies all of hard disks being sized in binary.
Literally every number in a computer is base-2, not just RAM addressing. Everything is ulimately bits, pins, and wires. The physical and logical interface between your oddly sized disk and your computer? Also some base-2.
Not everything is made from wires and transistors. And that's why these things are usually not measured in powers of 2:
- magnetic media
- optical media
- radio waves
- time
There's good reasons for having power-of-2 sectors (they need to get loaded into RAM), but there's really no compelling reason to have a power-of-2 number of sectors. If you can fit 397 sectors, only putting in 256 is wasteful.
Since everything ultimately ends up inside a base-2 computer across base-2 bus that even if these media aren't subject to the same considerations it still makes sense to measure them that way.
The choice would be effectively arbitrary, the number of actual bits or bytes is the same regardless of the multiplier that you use. But since it's for a computer, it makes sense to use units that are comparable (e.g. RAM and HD).
Buses and networking fit best with base 10 bits (not bytes) per second for reasons that are hopefully obvious. But I agree with you that everything else naturally lends itself to base 2.
Nope. The first home computers like the C64 had RAM and sectors on disc, which in case of the C64 means 256 bytes. And there it is again, the smaller base of 1024.
Just later, some marketing assholes thought they could better sell their hard drives when they lie about the size and weasel out of legal issues with redefining the units.
This was one of the "lessons learnt" from the XZ incident. One of the (many) steps they took to avoid scrutiny was modifications that existed in the real tarball but not the repo.
I do value the inconvenience. When I put an album on, I put an album on. I don't hit next, random, go wandering off down rabbitholes. I put the album on.
And I do see the cost as a feature, somewhat. It feels like I got something for my money, in a way that paying for a zip doesn't.
What you'll tend to notice with "willing participants" is that they're not looking for truth, they're looking for confirmation. No-one asks for proof when you tell them what they want to hear.
Propagation might be a useful way to visualise it, but doesn't match reality unless every cache is a warm cache.
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