The main purpose here is to show that hard drive makers are not trying to scam anybody with the way they measure sizes. They have done it the same way since at least 1980. What happened is that programmers foolishly applied a technical limitation of RAM sizing to the measurement of all capacity values, possibly starting in 1984.
Pointing out: OSX and Ubuntu both display base-10 units in their default GUI, and this is correct.
My question: Can anyone demonstrate a time when magnetic storage media was ever sold with the measurements used by RAM (base-2)?
According to the wikipedia linked below, the first operating system to screw up and use base-2 on hard drive storage was the Macintosh OS, in 1984. They were 'improving' the experience by using abbreviations, rather than the typical listing of exact amounts down to the byte, like MS-DOS.
This is the divergence between base-2 and base-10 as capacities grow:
This is from: http://en.wikipedia.org/wiki/Binary_prefix#Inconsistent_use_of_units
A bunch of background rambling:
Kilobyte(KB) = 1000 bytes. Kibibyte(KiB) = 1024.
Yes, this is what the ISO/IEC 80000 standard has done to try to permanently fix this confusion.
For any readers who don't know, RAM is sold in base-2 units because RAM, at least originally, had to connect to an address bus that directly activates the memory cells that are going to be read. This required some kind of segmentation by address-lines, hence a requirement that any unit of RAM be a power of 2 size.
In the 1960s, computer designers knew using K/k was a bad idea since it already meant 1000(or Kelvin), but every other symbol idea seemed worse, and so K came into use for 1024 bytes of RAM, as it was convenient and the extra 24 bytes were no big deal, particularly when some computers were lucky to have 4K. This corruption of meaning then fanned out, growing larger as the power of 2 diverges from base-10.
After everybody was 'educated' about what a kilobyte of RAM was(without explaining why), certain people, particularly OS and app programmers, proceded to use the RAM definition everywhere else.
But there is no evidence it was being used by storage vendors, and especially not in network capacities.(kilobit,megabit,gigabit per second are all base-10, as well as frequencies Mhz/Ghz)
Storage has typically been addressed through LBA (block numbers) or a physical address (cluster/head/sector) method, which does not imply a base-2 limitation. The only concession was to eventually use a 512-byte sector as the standard. Before that, sector sizes could vary greatly without a base-2 connection.
The Apple Lisa/Mac floppy was called 400K or 800K. The PC 1.44MB floppy was 1,440K, a strange mix of base-2 and base-10, and of course unformatted media was sometimes advertised as 2.0MB, meaning who knows what. Probably 2,000,000 bytes, since the '2M' floppy format was able to get 2019328 stuffed onto one.
The Apple Lisa ProFile Hard Drive (only $3499 for 5MB in Sep 1981, with 10MB available!) used a Seagate ST-506 internally(Seagate first shipped in 1980). This drive has 256-byte sectors, and lists an unformatted capacity of 6.38/12.76MB, or 5.0/10.0MB formatted. Formatted in this case likely means low-level formatted. Using the spec sheet, this means they presented the following bytes of storage to the file system: 5,013,504, or 10,027,008 bytes. Nowhere do you see any relation to base-2, except in the sector-size. The spec for it is here: http://bitsavers.informatik.uni-stuttgart.de/pdf/seagate/ST412_OEMmanual_Apr82.pdf
If you read that spec and think anybody was playing a marketing game with numbers, you're nuts. But if you do think it is a game, then Apple and Seagate were already ripping people off to the tune of 229,000 bytes on a 5MB drive. or 4.5%. Or $157.45.
On the bright side, if RAM ever starts being measured in base-10, your 64GiB of RAM will now be 68.7GB. But your 4TB hard drive will still be 4TB.
Pointing out: OSX and Ubuntu both display base-10 units in their default GUI, and this is correct.
My question: Can anyone demonstrate a time when magnetic storage media was ever sold with the measurements used by RAM (base-2)?
According to the wikipedia linked below, the first operating system to screw up and use base-2 on hard drive storage was the Macintosh OS, in 1984. They were 'improving' the experience by using abbreviations, rather than the typical listing of exact amounts down to the byte, like MS-DOS.
This is the divergence between base-2 and base-10 as capacities grow:
A bunch of background rambling:
Kilobyte(KB) = 1000 bytes. Kibibyte(KiB) = 1024.
Yes, this is what the ISO/IEC 80000 standard has done to try to permanently fix this confusion.
For any readers who don't know, RAM is sold in base-2 units because RAM, at least originally, had to connect to an address bus that directly activates the memory cells that are going to be read. This required some kind of segmentation by address-lines, hence a requirement that any unit of RAM be a power of 2 size.
In the 1960s, computer designers knew using K/k was a bad idea since it already meant 1000(or Kelvin), but every other symbol idea seemed worse, and so K came into use for 1024 bytes of RAM, as it was convenient and the extra 24 bytes were no big deal, particularly when some computers were lucky to have 4K. This corruption of meaning then fanned out, growing larger as the power of 2 diverges from base-10.
After everybody was 'educated' about what a kilobyte of RAM was(without explaining why), certain people, particularly OS and app programmers, proceded to use the RAM definition everywhere else.
But there is no evidence it was being used by storage vendors, and especially not in network capacities.(kilobit,megabit,gigabit per second are all base-10, as well as frequencies Mhz/Ghz)
Storage has typically been addressed through LBA (block numbers) or a physical address (cluster/head/sector) method, which does not imply a base-2 limitation. The only concession was to eventually use a 512-byte sector as the standard. Before that, sector sizes could vary greatly without a base-2 connection.
The Apple Lisa/Mac floppy was called 400K or 800K. The PC 1.44MB floppy was 1,440K, a strange mix of base-2 and base-10, and of course unformatted media was sometimes advertised as 2.0MB, meaning who knows what. Probably 2,000,000 bytes, since the '2M' floppy format was able to get 2019328 stuffed onto one.
The Apple Lisa ProFile Hard Drive (only $3499 for 5MB in Sep 1981, with 10MB available!) used a Seagate ST-506 internally(Seagate first shipped in 1980). This drive has 256-byte sectors, and lists an unformatted capacity of 6.38/12.76MB, or 5.0/10.0MB formatted. Formatted in this case likely means low-level formatted. Using the spec sheet, this means they presented the following bytes of storage to the file system: 5,013,504, or 10,027,008 bytes. Nowhere do you see any relation to base-2, except in the sector-size. The spec for it is here: http://bitsavers.informatik.uni-stuttgart.de/pdf/seagate/ST412_OEMmanual_Apr82.pdf
If you read that spec and think anybody was playing a marketing game with numbers, you're nuts. But if you do think it is a game, then Apple and Seagate were already ripping people off to the tune of 229,000 bytes on a 5MB drive. or 4.5%. Or $157.45.
On the bright side, if RAM ever starts being measured in base-10, your 64GiB of RAM will now be 68.7GB. But your 4TB hard drive will still be 4TB.
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