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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."
If you read closely, you'll see that the summary is kind of misleading. What canonical is actually doing is using SI prefixes for base-10 units, and IEC prefixes for base-2 units.
In other words, they will use 1kB for 1000 bytes and 1KiB for 1024 bytes. This is a good thing, it just means the UI should be consistent and you don't need to second-guess.
Hi there
Sorry, 512 or whatever base-2 sector size is not arbitrary - the disk controlling hardware / buffers / controllers / channels / etc and especially the transfer sizes, multipliers in headers, and so on are (still) base-2. If you ever do performance / capacity calculations or estimates for storage size, etc, you very fast find base-2 very handy.
The disk size error is not a big deal - there always is an overhead that changes by storage type, file system, fixed physical characteristics, key / data compression used, replication, whatever - so? The public (and I think many in IT) really don't know and/or have to know more than if they have enough or need more!
Because the context is a problem every time you mix computers and what you're doing on a computer. Let's say you record a CD, 16 bits/sample @ 44.1kHz. That's a bitrate of 16 * 44.1 = 705.6 kbit/s second right? If I want to send it over the LAN too? What if I need to allocate a memory buffer, is it still 705.6 kbit/s? And what if I want to store it to disk, do I need to allocate 705.6 kbit per second of music? Computers aren't not remotely consistent with themselves, a 100 Mbit LAN is 100,000,000 bits/second. Hard drives too but they're hardly the only ones, floppies weren't even consistent with themselves most being 1.44*1000*1024 bytes.
Things get confusing all the time because a 1 MB, 1 KHz (1024*1024*1000) bus is not equal to a 1 kB, 1MHz bus (1024*1000*1000) which is why everyone dealing with networks never used kilo = 1024. The 56k modem is 56,000 bits, ISDN is 64,000 bits and so on right up to SATA 6Gbit/s which is 6,000,000,000 Gbit/s (and even more confusing because it's in 8/10 bit encoding, but that's another story). So both inside and outside the machine we're switching between base 2 and base 10 all the time.
A particularly confusing item was codecs. Should they follow the "size" standard so a 128 kbit/s MP3 would take up 128 kbit/s, or the network standard so that a 128 kbit/s would take 128 kbit/s of network bandwidth? I think now most settled on k = 1000, that is to say if you encode a one second clip at 128 kbit/s it'll only take up 125 kbit on your disk. Confusing as fuck? Hell yeah. Let's just settle this and be done with it, with the i = base 2, without it base 10. Just forget the lame names, and let the prefixes do the talking. MB = megabyte, MiB = megabyte. That's what I'm doing at least.
Live today, because you never know what tomorrow brings
he kilo prefix is derived from the Greek word ("chilioi"), meaning thousand. It was originally adopted by Antoine Lavoisier and his group in 1795, and introduced into the metric system in France with its establishment in 1799.
So while "SI" wasn't around. It was already as established standard