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1 kilobyte is precisely 1000 bytes?

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Re: 1 kilobyte is precisely 1000 bytes?

#101

Post by snozolli »

cedilla wrote: post #20
nerdsniper wrote: post #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 Devic…

You've got it exactly the wrong way around. And that with such great confidence! There was always a confusion about whether a kilobyte was 1000 or 1024 bytes. Early diskettes always used 1000, only when the 8 bit home computer era started was the 1024 convention firmly established. Before that it made no sense to talk about kilo as 1024. Earlier computers measured space in records and words, and I guess you can see h…

only when the 8 bit home computer era started was the 1024 convention firmly established.

That's the microcomputer era that has defined the vast majority of our relationship with computers.

IMO, having lived through this era, the only people pushing 1,000 byte kilobytes were storage manufacturers, because it allows them to bump their numbers up.

https://www.latimes.com/archives/la-xpm-2007-nov-03-fi-seaga...

Re: 1 kilobyte is precisely 1000 bytes?

#102

Post by jijijijij »

Metric prefixing should only be used with the unit bit. There is no confusion there. I mean, if you would equate a bit with a certain voltage threshold, you could even argue about fractional bits.

Approximating metric prefixing with kibi, Mibi, Gibi... is confusing because it doesn't make sense semantically. There is nothing base-10-ish about it.

I propose some naming based on shift distance, derived from the latin iterativum. https://en.wikipedia.org/wiki/Latin_numerals#Adverbial_numer...

* 2^10, the kibibyte, is a deci (shifted) byte, or just a 'deci'

* 2^20, the mibibyte, is a vici (shifted) byte, or a 'vici'

* 2^30, the gibibyte, is a trici (shifted) byte, or a 'trici'

I mean, we really only need to think in bytes for memory addressing, right? The base doesn't matter much, if we were talking exabytes, does it?

Re: 1 kilobyte is precisely 1000 bytes?

#103

Post by waffletower »

The author decidedly has expert syndrome -- they deny both the history and rational behind memory units nomenclature. Memory measurements evolved utilizing binary organizational patterns used in computing architectures. While a proud French pedant might agree with the decimal normalization of memory units discussed, it aligns more closely to the metric system, and it may have benefits for laypeople, it fails to account for how memory is partitioned in historic and modern computing.

Re: 1 kilobyte is precisely 1000 bytes?

#104

Post by nayuki »

ValdikSS wrote: post #90
nayuki wrote: post #38

> 1 kilobyte is precisely 1000 bytes Agreed. For the naysayers out there, consider these problems: * You have 1 "MB" of RAM on a 1 MHz system bus which can transfer 1 byte per clock cycle. How many seconds does it take to read the entire memory? * You have 128 "GB" of RAM and you have an empty 128 GB SSD. Can you successfully hibernate the computer system by storing all of RAM on the SSD? * My camera shoots 6000×4000…

Well, you're joking, but the entire RAM industry still lists their chips in Gb (gigaBITS) to avoid confusion. 32 Gb ram chip = 4 GiB of RAM.

That's still wrong and you've solved nothing. 32 Gb = 32 000 000 000 bits = 4 000 000 000 bytes = 4 GB (real SI gigabytes).

If you think 32 Gb are binary gibibits, then you've disagreed with Ethernet (e.g. 2.5 Gb/s), Thunderbolt (e.g. 40 Gb/s), and other communication standards.

That's why I keep hammering on the same point: Creating context-dependent prefixes sows endless confusion. The only way to stop the confusion is to respect the real definitions.

Re: 1 kilobyte is precisely 1000 bytes?

#105

Post by BrandoElFollito »

nerdsniper wrote: post #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 Devic…

> Edit: I'm wrong. Older experience has corrected me - there has always been ambiguity "And that with such great confidence!", indeed.

Kudos for getting back. (and closing the tap of "you are wrong" comments :))

Re: 1 kilobyte is precisely 1000 bytes?

#106

Post by nayuki »

wvenable wrote: post #94
nayuki wrote: post #38

> 1 kilobyte is precisely 1000 bytes Agreed. For the naysayers out there, consider these problems: * You have 1 "MB" of RAM on a 1 MHz system bus which can transfer 1 byte per clock cycle. How many seconds does it take to read the entire memory? * You have 128 "GB" of RAM and you have an empty 128 GB SSD. Can you successfully hibernate the computer system by storing all of RAM on the SSD? * My camera shoots 6000×4000…

> The computer industry abused these definitions because 1000 is close to 1024, creating endless confusion. They didn't abuse the definitions. It's simply the result of dealing with pins, wires, and bits. For your problems, for example, you won't ever have a system with 1 "MB" of RAM where that's 1,000,000 bytes. The 8086 processor had 20 address lines, 2^20, that's 1,048,576 bytes for 1MB. SI units make no sense for…

> They didn't abuse the definitions.

Yes they did. Kilo- means 1000 in SI/metric. The computer industry decided, "Gee that looks awfully close to 1024. Let's sneakily make it mean 1024 in our context and sell our RAM that way".

> It's simply the result of dealing with pins, wires, and bits. For your problems, for example, you won't ever have a system with 1 "MB" of RAM where that's 1,000,000 bytes.

I'm not disputing that. I'm 100% on board with RAM being manufactured and operated in power-of-2 sizes. I have a problem with how these numbers are being marketed and communicated.

> SI units make no sense for computers.

Exactly! Therefore, use IEC 60027 prefixes like kibi-, because they are the ones that reflect the binary nature of computers. Only use SI if you genuinely respect SI definitions.

Re: 1 kilobyte is precisely 1000 bytes?

#107

Post by waffletower »

pjdesno wrote: post #79

I had a computer architecture prof (a reasonably accomplished one, too) who thought that all CS units should be binary, e.g. Gigabit Ethernet should be 931Mbit/s, not 1000MBit/s. I disagreed strongly - I think X-per-second should be decimal, to correspond to Hertz. But for quantity, binary seems better. (modern CS papers tend to use MiB, GiB etc. as abbreviations for the binary units) Fun fact - for a long time consu…

I can see a precision argument for binary represented frequencies. A systems programmer would value this. A musician would not.

Re: 1 kilobyte is precisely 1000 bytes?

#108

Post by jltsiren »

pif wrote: post #53
marssaxman wrote: post #47

Earlier quoted context omitted.

That is a prescriptivist way of thinking about language, which is useful if you enjoy feeling righteous about correctness, but not so helpful for understanding how communication actually works. In reality-reality, "kilobyte" may mean either "1000 bytes" or "1024 bytes", depending on who is saying it, whom they are saying it to, and what they are saying it about. You are free to intend only one meaning in your own com…

I understand the usual meaning, but I use the correct meaning when precision is required.

When precision is required, you either use kibibytes or define your kilobytes explicitly. Otherwise there is a real risk that the other party does not share your understanding of what a kilobyte should mean in that context. Then the numbers you use have at most one significant figure.

Re: 1 kilobyte is precisely 1000 bytes?

#110

Post by [deleted] »

card_zero wrote: post #59
Sophira wrote: post #30

Earlier quoted context omitted.

> Early diskettes always used 1000 Even worse, the 3.5" HD floppy disk format used a confusing combination of the two. Its true capacity (when formatted as FAT12) is 1,474,560 bytes. Divide that by 1024 and you get 1440KB; divide that by 1000 and you get the oft-quoted (and often printed on the disk itself) "1.44MB", which is inaccurate no matter how you look at it.

I'm not seeing evidence for a 1970s 1000-byte kilobyte. Wikipedia's floppy disk page mentions the IBM Diskette 1 at 242944 bytes (a multiple of 256), and then 5¼-inch disks at 368640 bytes and 1228800 bytes, both multiples of 1024. These are sector sizes. Nobody had a 1000-byte sector, I'll assert.

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