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1 kilobyte is precisely 1000 bytes?

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Re: 1 kilobyte is precisely 1000 bytes?

#2
The entire reason "storage vendors prefer" 1000-based kilobytes is so that they could misrepresent and over-market their storage capacities, getting that 24-bytes per-kb of expectation-vs-reality profit.

It's the same reason—for pure marketing purposes—that screens are measured diagonally.

Re: 1 kilobyte is precisely 1000 bytes?

#3
I'm suprised they didn't mention kibibyte. (Edit: they did) There are plenty of applications where power-of-2 alignment are useful or necessary. Not addressing that and just chastising everyone for using units wrong isn't particularly helpful. I guess we can just all switch to kibibytes, except the HDD manufacturers.

Re: 1 kilobyte is precisely 1000 bytes?

#4

I'm suprised they didn't mention kibibyte. (Edit: they did) There are plenty of applications where power-of-2 alignment are useful or necessary. Not addressing that and just chastising everyone for using units wrong isn't particularly helpful. I guess we can just all switch to kibibytes, except the HDD manufacturers.

It's at the end, in the "What are the standards units?" section.

Re: 1 kilobyte is precisely 1000 bytes?

#6

I'm suprised they didn't mention kibibyte. (Edit: they did) There are plenty of applications where power-of-2 alignment are useful or necessary. Not addressing that and just chastising everyone for using units wrong isn't particularly helpful. I guess we can just all switch to kibibytes, except the HDD manufacturers.

It's at the end, in the "What are the standards units?" section.

So it does. I guess I skimmed a little too hard.

Re: 1 kilobyte is precisely 1000 bytes?

#7

I'm suprised they didn't mention kibibyte. (Edit: they did) There are plenty of applications where power-of-2 alignment are useful or necessary. Not addressing that and just chastising everyone for using units wrong isn't particularly helpful. I guess we can just all switch to kibibytes, except the HDD manufacturers.

The second half of the article is entirely about kibibyte and the other IEC units.

Re: 1 kilobyte is precisely 1000 bytes?

#8
post #2

The entire reason "storage vendors prefer" 1000-based kilobytes is so that they could misrepresent and over-market their storage capacities, getting that 24-bytes per-kb of expectation-vs-reality profit. It's the same reason—for pure marketing purposes—that screens are measured diagonally.

Not sure about that, SSDs historically have followed base-2 sizes (think of it as a legacy from their memory-based origins). What does happen in SSDs is that you have overprovisioned models that hide a few % of their total size, so instead of a 128GB SSD you get a 120GB one, with 8GB "hidden" from you that the SSD uses to handle wear leveling and garbage collection algorithms to keep it performing nicely for a longer period of time.

Re: 1 kilobyte is precisely 1000 bytes?

#9
Final edit:

This ambiguity is documented at least back to 1984, by IBM, the pre-eminent computer company of the time.

In 1972 IBM started selling the IBM 3333 magnetic disk drive. This product catalog [0] from 1979 shows them marketing the corresponding disks as "100 million bytes" or "200 million bytes" (3336 mdl 1 and 3336 mdl 11, respectively). By 1984, those same disks were marketed in the "IBM Input/Output Device Summary"[1] (which was intended for a customer audience) as "100MB" and "200MB"

0: (PDF page 281) "IBM 3330 DISK STORAGE" http://electronicsandbooks.com/edt/manual/Hardware/I/IBM%20w...

1: (PDF page 38, labeled page 2-7, Fig 2-4) http://electronicsandbooks.com/edt/manual/Hardware/I/IBM%20w...

Also, hats off to http://electronicsandbooks.com/ for keeping such incredible records available for the internet to browse.

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Edit: The below is wrong. Older experience has corrected me - there has always been ambiguity (perhaps bifurcated between CPU/OS and storage domains). "And that with such great confidence!", indeed.

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The article presents wishful thinking. The wish is for "kilobyte" to have one meaning. For the majority of its existence, it had only one meaning - 1024 bytes. Now it has an ambiguous meaning. People wish for an unambiguous term for 1000 bits, however that word does not exist. People also might wish that others use kibibyte any time they reference 1024 bytes, but that is also wishful thinking.

The author's wishful thinking is falsely presented as fact.

I think kilobyte was the wrong word to ever use for 1024 bytes, and I'd love to go back in time to tell computer scientists that they needed to invent a new prefix to mean "1,024" / "2^10" of something, which kilo- never meant before kilobit / kilobyte were invented. Kibi- is fine, the phonetics sound slightly silly to native English speakers, but the 'bi' indicates binary and I think that's reasonable.

I'm just not going to fool myself with wishful thinking. If, in arrogance or self-righteousness, one simply assumes that every time they see "kilobyte" it means 1,000 bytes - then they will make many, many failures. We will always have to take care to verify whether "kilobyte" means 1,000 or 1,024 bytes before implementing something which relies on that for correctness.

Re: 1 kilobyte is precisely 1000 bytes?

#10
And a megabyte is depending on the context precisely 1000x1000=1,000,000 or 1024x1024=1,048,576 bytes*, except when you're talking about the classic 3.5 inch floppy disks, where "1.44 MB" stands for 1440x1024 bytes, or about 1.47 true MB or 1.41 MiB.

* Yeah, I read the article. Regardless of the IEC's noble attempt, in all my years of working with people and computers I've never heard anyone actually pronounce MiB (or write it out in full) as "mebibyte".

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