Ubuntu Policy: prefixes for multiples of units

Thorsten Wilms t_w_ at freenet.de
Wed Sep 24 18:55:26 BST 2008

On Wed, 2008-09-24 at 18:26 +0100, Scott James Remnant wrote:

> Despite common belief, in general the industry (largely thanks to its
> marketing department) has actually settled on factors of powers of ten
> for these prefixes.  (What was an 80GB drive may now be sold as an 85GB
> drive.)
> In particular, the following multiples must always use powers of ten as
> their factor:
>  * Disk and partition sizes, space used and remaining.
>  * File sizes.
>  * Bandwidth and transfer rates.
>  * Data transfer totals.
> Since RAM manufactures still quote sizes using powers of two as their
> factor, the following multiples must also match:
>  * Available, used and free RAM and swap.
>  * Sizes of software and files in memory.

I as a somewhat technical inclined user would expect powers of 2 to be
used everywhere.

A naive user who doesn't know anything about this issue, will still
expect that KB, MB and so on always mean the same thing.

I think the cost of inconsistency once between info on hardware purchase
and what the system says is much less of an issue than continued
inconsistency within the system.

Oh, and the kibi/mebi thing will never catch on if OSes don't use it.
Chicken and egg.

Thorsten Wilms

thorwil's design for free software:

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