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Ubuntu Will Switch To Base-10 File Size Units In Future Release
CyberDragon777 writes "Ubuntu's future 10.10 operating system is going to make a small, but contentious change to how file sizes are represented. Like most other operating systems using binary prefixes, Ubuntu currently represents 1 kB (kilobyte) as 1024 bytes (base-2). But starting with 10.10, a switch to SI prefixes (base-10) will denote 1 kB as 1000 bytes, 1 MB as 1000 kB, 1 GB as 1000 MB, and so on."
HD manufacturers are presenting the sizes correctly. SI prefix = hard-defined base-10, it's just computer engineering and computer sciences that broke the established standard.
As long as they use the correct prefix, I don't really mind whether they use base 2 or 10 to display the numbers.
RAM sizes are naturally powers of 2 due to how the individual memory cells are addressed, so it makes sense for RAM capacity to always be listed in GiB.
Hard drives, on the other hand, have nothing that is fundamentally based on a power of 2. They arbitrarily use a sector size of 512 (or 4096) bytes, but everything else (number of heads, number of tracks, average number of sectors per track) has no power-of-2 connection. Therefore there's nothing wrong with reporting their size in SI notation.
The original shorthand of calling 1024 bytes a "K" was not too bad because it's only a 2.4% error. However the error gets worse as you go up each level, and by the time you're talking about a TB/TiB it's something that people actually care about.
I've used Ubuntu exclusively on my desktops for several years now. It's nice to know that I can always switch to another distro when they do something BAT SHIT INSANE like this: https://wiki.ubuntu.com/UnitsPolicy
Change the GUI window buttons from right to left? Meh. Change the way file sizes are read so that User X and User Y see different file sizes using the same filesystem, even potentially the same remotely mounted disk?
Now I have to draft a letter to our research department telling them to stay the hell away from Ubuntu because their data will potentially be wrong (unless they take pains to remember the kilo=/=kibi switch).
when the C64 came out with 64K No-ONE doubted it had 65536 Bytes of RAM. if it would came out now, there would be confusion, so the kibi-business introduced confusion. people who don't understand the difference between binary and decimal have no place in IT
Yes, I'm left. You have a problem with that?
I'm surprised by the majority here that is against this. What kind of nerds exactly are you?
SI prefixes are defined as base-10, period. Every other use is simply wrong.
Being consistently wrong for a very long time doesn't make it better, it is just proof of
an unwillingness to admit to a stupid initial mistake you didn't even make yourself.
As nerds, you're supposed to be better than that.
How can you be all for standards-compliance with browsers and rile against a much
stronger, decades-old ISO standard (which is based on a centuries old definition from the
beginning of the metric system - "kilo" has been 1000 for over 200 years)?
On the other hand, you are the same crowd regularly writing about "mbit/s" while meaning "Mbit/s",
thereby being off by just a tiny, unimportant, paltry factor of a billion.
Seriously, what's wrong with you?
-- an annoyed scientist
Other posters have pointed out that bits and bytes are not SI units, but they've not pointed out that we use 1024 because it's more useful. We use base 10 for physical quantities because it means that you can very easily do base-10 logarithms and most arithmetic on physical quantities is easier if you can do logarithms on the base that you use in your head.
Storage is always indexed by some binary quantity, so you need to do base-2 logarithms. You can trivially calculate how much space a 32-bit address space gives you: 2^32 bits, divide the 32 by 10 gives you 2^22 KB, 2^12 MB, 2^2 GB, 4GB. Try doing that with 1KB = 1000B in your head. You can easily tell how much space your 32-bit filesystem can store if it is addressing 512B blocks (the size of most hard disk blocks). 512 is 2^9, so it's 2^9 x 2^32 bytes. Add the exponents and you get 2^41 byes, or 2TB. What happens if we start using 4KB blocks instead? Well, 4 is 2^2, K means 2^10, so 2^12 x 2^32 = 2^44, or 16TB.
Redefining KB makes these calculations harder. The only kind of calculations it makes easier are things that involve bytes and some other SI units that use the SI prefixes in the same equation. About the only other SI quantity that you ever see in an equation with bytes is seconds and you almost never talk about kiloseconds or megaseconds...
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Actually, they are. This is most likely for the exact same reason as apple likely did it –reduced support costs. They don't need to deal with shit tons of people complaining that their 1000GB disk isn't 1000GB, it's only 931.3GB.
Along with of course the most obvious reason – it's *correct* that way.
And they accomplish this by measuring wrong? Great effing job!
Wrong? By who's standard, the SI standard, the ISO standard and the IEEE standard all agree on this point.
But there are many applications and areas which are not appropriate to shoehorn into the decimal system. Binary computer memory sizes are one such application. It is not appropriate to group base 2 numbers using a base 10 units.
I agree entirely. However, SI prefixes *are* in base 10, and just redefining them in specific contexts to mean something in base 2 is unnecessarily confusing. Kilo is accepted to mean thousand, and redefining it in specific contexts to mean 2^10 is just unreasonable. To use your phrase, it's not appropriate to shoehorn this system of decimal prefixes into describing a naturally binary system (which is precisely what happened in CS).
I understand it's how we've been doing things for decades, but why on earth are so many CS people arguing *against* decreasing ambiguity? I find the whole KiB thing to be a relatively elegant solution, which maintains the familiar letters so there's nothing new to learn, but makes it clear what units you're using. The only reason to resist it that I can see is just blind and unthinking resistance to change -- the exact same reason so many people resist the metric system and SI at all.
You seem to be arguing "if it ain't broke, don't fix it", but I think it is a little broke and we should fix it.