Bug #9374

Don't use powers of 1000 for ISO size on the download page

Added by anonym 2015-05-12 09:36:43 . Updated 2016-01-27 13:33:46 .

Status:
Resolved
Priority:
Low
Assignee:
sajolida
Category:
Installation
Target version:
Tails_2.0
Start date:
2015-05-12
Due date:
% Done:

100%

Feature Branch:
web/9374-iso-size-units
Type of work:
End-user documentation
Blueprint:

Starter:
Affected tool:
Installation Assistant
Deliverable for:

Description

Since Feature #7417 we show the ISO image size on the download page, and it uses powers of 1000 and the unit “MB”, which is completely correct. But it risks confusing users, since reason lost this battle (at least so far) and an inconsistent use of the power vs unit is what users is likely to be exposed to. Here’s what I looked at to draw that conclusion:

  • Firefox shows the number in MiB:s but incorrectly uses the unit “MB”
  • Chromium/Google Chrome shows the number in MiB:s but incorrectly uses the unit “MB”
  • Windows 8.1’s explorer shows the number in MiB:s but incorrectly uses the unit “MB”
  • KDE’s Dolphin shows the number in MiB:s and correctly uses the unit “MiB”
  • GNOME’s Nautilus shows the number in MB:s and correctly uses the unit “MB”

So, showing the number in MiB:s but incorrectly using the unit “MB” is what most users will be exposed to, in particular when downloading the file. The difference becomes very noticeable given our ISO image size, e.g. for Tails 1.4 its 971 MB vs 926 MiB (in correct units!). With the current situation users may think they are downloading a Tails containing 45 “MB” worth of NSA backdoors, or whatever.

Subtasks

Related issues

Related to Tails - Feature #7417: Mention the ISO file size on the download page Resolved 2014-06-17
Related to Tails - Feature #15104: Favor consistency over accuracy when displaying ISO size (GB vs GiB) Resolved 2017-12-25
Blocks Tails - Feature #9438: Assistant: Automatically include the size of the ISO image in the router Resolved 2015-05-21

History

#1 Updated by anonym 2015-05-12 09:36:53

  • related to Feature #7417: Mention the ISO file size on the download page added

#2 Updated by intrigeri 2015-05-12 09:54:07

> * GNOME’s Nautilus shows the number in MB:s and correctly uses the unit “MB”

I should check if that’s the case in Ubuntu as well (https://wiki.ubuntu.com/UnitsPolicy suggests it should use powers of two).

#3 Updated by sajolida 2015-05-12 17:55:18

  • Assignee set to sajolida

#4 Updated by sajolida 2015-05-13 10:50:49

  • Assignee changed from sajolida to tchou

While working on this I checked that Nautilus was consistent with what we are proposing. But now I realize that Nautilus is in the minority here (showing numbers in MB).

Nautilus has been discussed this here https://bugzilla.gnome.org/show_bug.cgi?id=695146 and it seems like they’re not going to decide something really soon.

I’m actually more concerned about the number which is displayed than the correctness of the unit (seeing how many other project do that wrong). But I’m worried about the fact that we can’t find a number that works both in Firefox, Chromium, Windows, and Tails. (Apparently OS X does MB like Nautilus.)

So what about removing that indication and at least not generate more confusion from that?

Tchou, what do you think? As you were the one to propose this initially and we’re doing it again in our new design.

#5 Updated by BitingBird 2015-05-13 16:24:07

Could we say “the size is 971 MB (926 MiB)” so that users are confident if hey have either sizes showing?

#6 Updated by sajolida 2015-05-21 09:58:03

  • blocks Feature #9438: Assistant: Automatically include the size of the ISO image in the router added

#7 Updated by intrigeri 2015-05-22 17:19:24

> So what about removing that indication […]

I’m not sure I understand what this means exactly.

#8 Updated by sajolida 2015-05-26 13:08:43

Removing that indication, means stop displaying any ISO image size on the download page. If we don’t give that information, the unit can’t be wrong :)

#9 Updated by intrigeri 2015-05-26 15:12:14

> Removing that indication, means stop displaying any ISO image size on the download page. If we don’t give that information, the unit can’t be wrong :)

Perhaps stating something like “ca. 1GB” would achieve the initial goal (giving users an idea of the download size), and would not have the problems this ticket is about?

#10 Updated by tchou 2015-05-27 10:33:04

  • Assignee changed from tchou to sajolida
  • QA Check set to Ready for QA

Maybe we can have “ca. 1GB”, and a popover on hover (http://getbootstrap.com/javascript/#popovers-examples) with details.

#11 Updated by sajolida 2015-05-27 15:24:12

  • QA Check changed from Ready for QA to Dev Needed

I’m fine with saying “±1GB” (I didn’t know what ‘ca.’ means before asking Wikipedia).

So here is what I’ll do:

  • Try displaying both MB and MiB as BitingBird proposed and see how it looks.
  • Try displaying “±1GB”.
  • Try to implement a popover with ikiwiki toogle. As doing this with bootstrap is blocked by at least Feature #9314 and Feature #9216 and maybe a wider debate if we want to start usin bootstrap in other places then the Installation Assistant (which is the current compromise).

Marking this as “Dev Needed” now.

#12 Updated by anonym 2015-05-27 16:07:24

sajolida wrote:
> * Try displaying “±1GB”.

AFAIK (and Wikipedia too the meaning of “±” is not “approximately” but “positive or negative”, i.e. the Tails image is either 1GB or –1GB, whatever that means. Let’s not do that. :)

What about “Approx. 1GB”?

#13 Updated by BitingBird 2015-06-04 02:17:21

Today, a user specifically sent a whisperback report to thank us for adding the iso size. I think it’s useful and should not be removed :)

#14 Updated by sajolida 2015-06-25 03:20:49

  • Assignee deleted (sajolida)
  • QA Check changed from Dev Needed to Ready for QA
  • Feature Branch set to web/9374-iso-size-units

Ok, so I tried displaying both MB and MiB. Please, try to build that branch and see how it looks. Tell me if you like it. Otherwise I’ll fall back to saying “(about 1 GB)”.

#15 Updated by BitingBird 2015-06-25 06:59:35

  • Assignee set to BitingBird

I’ll try to review it in time for 1.4.1 but I don’t have much time those days.

#16 Updated by intrigeri 2015-06-28 02:09:16

  • Status changed from Confirmed to In Progress

#17 Updated by cypherpunks 2015-06-29 05:18:34

To me, a megabyte will be 2^20 until the day I die.

That said, why not list the file size in bytes instead? I like knowing the exact file size so I can check it before file verification.

#18 Updated by sajolida 2015-06-30 01:26:24

I agree with you, displaying bytes would remove the ambiguity on the multiplier (mega, mebi). But the problem here is not actually about being technical “right” (other we would put MiB and be done with it), but about matching what people will see in their operating system; and here stuff gets more complicated as anonym pointed out in the description of this ticket.

#19 Updated by cypherpunks 2015-06-30 10:43:10

Listing size in bytes is about precision. When I download something that has a slightly different size than it’s supposed to have, I know that something is wrong even before the file verification process.

A kilobyte is 1024 bytes. It doesn’t need a new name. Computer scientists have not has it wrong all along.

#20 Updated by intrigeri 2015-07-01 02:57:49

  • Type of work changed from Discuss to End-user documentation

#21 Updated by BitingBird 2015-07-02 06:16:42

  • Assignee changed from BitingBird to sajolida
  • QA Check changed from Ready for QA to Info Needed

You forgot to push the branch, so I can’t review :)

#22 Updated by sajolida 2015-07-03 00:55:50

> Listing size in bytes is about precision. When I download something
> that has a slightly different size than it’s supposed to have, I know
> that something is wrong even before the file verification process.

Right, listing size in bytes would be about “precision” but it’s not our
goal here. Our goal here is to provide a number that’s “good enough”
(not necessarily super precise) for people to:

  • Know if they will have enough space on their disk
  • Know whether the download was interrupted or not
  • Match the number they see in there file browser (on Linux, Windows, or
    MAC).

I think that MB or MiB is precise enough to math the first two goals,
and that displaying the size in bytes fails to match the third goal.

#23 Updated by intrigeri 2015-07-03 01:00:35

  • Target version changed from Tails_1.4.1 to Tails_1.5

#24 Updated by sajolida 2015-07-03 01:16:13

  • Assignee changed from sajolida to BitingBird
  • QA Check changed from Info Needed to Ready for QA

Done now, sorry.

#25 Updated by BitingBird 2015-07-04 06:19:55

  • Assignee changed from BitingBird to sajolida
  • QA Check changed from Ready for QA to Pass

Looks good, please merge :)

#26 Updated by sajolida 2015-07-05 07:26:28

  • Status changed from In Progress to Resolved
  • % Done changed from 0 to 100

Applied in changeset commit:08a8de07b2e9684b7020423703a7708427ef344c.

#27 Updated by sajolida 2015-07-05 07:34:28

  • Status changed from Resolved to In Progress
  • % Done changed from 100 to 70
  • QA Check changed from Pass to Dev Needed

Actually, my CSS layout breaks with “1.4.1” which is longer then “1.4” so I merged this but then reverted my change (through a carefull —force). I need to work on this more … :(

#28 Updated by sajolida 2015-07-05 07:48:18

  • Status changed from In Progress to Resolved
  • Assignee deleted (sajolida)
  • QA Check deleted (Dev Needed)

In the end I fixed it straight away… sorry for the mess :(

#29 Updated by sajolida 2015-11-13 03:54:43

  • Status changed from Resolved to In Progress
  • Target version changed from Tails_1.5 to Tails_1.8

While working on the Installation Assistant we reviewed a bit this decision and will inline only the size in MiB and the “MiB” unit (as proposed in the title of this ticket). For several reasons:

  • It will be the duty of the browser extension or the BitTorrent client to check that the download was interrupted and the ISO is complete.
  • We displaying this indication in many more places where it’s cumbersome to have both units.
  • We don’t believe that this difference is meaningful for most users and is worth the confusion that it will create (“Why are they two different sizes?”).

If people still have strong opinions about that. We could try to display both sizes until the user testing sessions and report back any finding.

That’s ee0092e. I’ll remove the double indication from /inc and the release process once the assistant replaced the old download page.

#30 Updated by sajolida 2015-12-17 03:04:21

  • Assignee set to sajolida
  • Target version changed from Tails_1.8 to Tails_2.0

#31 Updated by sajolida 2015-12-17 03:04:49

  • Affected tool set to Installation Assistant

Assigning this to me as this should be dealt with while working on the installation assistant.

#32 Updated by sajolida 2016-01-05 22:31:57

  • Priority changed from Normal to Low

#33 Updated by sajolida 2016-01-16 17:42:00

  • Assignee changed from sajolida to anonym
  • QA Check set to Ready for QA

Done in 34c2940..2072609. This branch should be merged for the first release after the official release of the installation assistant (otherwise there will be some glitches on /download). So I suggest you merge it right before the release but not now.

#34 Updated by anonym 2016-01-22 14:46:37

  • Status changed from In Progress to Fix committed
  • % Done changed from 70 to 100

Applied in changeset commit:22094311b1ee8187b248e438504d47cf81630485.

#35 Updated by anonym 2016-01-22 14:48:33

  • Assignee deleted (anonym)
  • QA Check changed from Ready for QA to Pass

#36 Updated by sajolida 2016-01-22 15:12:28

  • Assignee: sajolida

#37 Updated by intrigeri 2016-01-23 12:27:29

sajolida, I’m not sure what you tried to do but it seems to have failed.

#38 Updated by sajolida 2016-01-24 14:52:23

  • Assignee set to sajolida

#39 Updated by anonym 2016-01-27 13:33:46

  • Status changed from Fix committed to Resolved

#40 Updated by sajolida 2017-12-26 00:07:29

  • related to Feature #15104: Favor consistency over accuracy when displaying ISO size (GB vs GiB) added