ubuntuone-users team mailing list archive

[Natan Yellin <aantny@xxxxxxxxx>]

On Fri, Oct 2, 2009 at 2:32 PM, Steve Alexander <steve@xxxxxxxxxxxxx> wrote:

>
>  Yes, implementing a "Human" DCVS isn't easy. Dropbox, Apple's Time
>> Machine, and several other projects have all /tried/ to to do so, but as far
>> as I can tell they haven't succeeded. (It's gotten to the point where
>> Dropbox decided that it just wasn't worth keeping file-revisions and now
>> deletes revisions more than one month old. I haven't heard anyone complain,
>> so I doubt that the feature was at all popular.) Both Dropbox and Time
>> Machine remember small one-line edits that no one cares about. Its been
>> impossible to create a "Human" GUI for viewing revisions because there are
>> just too darn many revisions to be viewed.
>>
>
> I'm sure that Dropbox want to keep their user interfaces simple and
> intuitive, and this will be part of why their system works like this.
> There's an economic driver for this too, and I think this is very
> significant.
>
> Dropbox wants to sell 50GB of file storage at $10 per month.  That's a flat
> rate for a bunch of storage.
>
> They will be banking on most of their customers using only a fraction of
> the full amount of available storage, because Dropbox is a cloud-based
> service using Amazon S3, and so they will pay for only what users use, not
> the full amount they are offering to users.
>
> There's a problem with this approach if they are also offering to keep
> revisions indefinitely, or just remove revisions when the quota gets full.
>  The problem is, over time, most users will be using the full 50GB. part for
> "live" data and the rest for historical revisions.
>
> It costs Dropbox about the same amount to store a historical revision as it
> costs to store current revision of some files.  But the value to the user is
> totally different.  So, they will want keep only the most valuable
> revisions, and remove the rest.  I guess that's why they've come up with
> this particular policy of removing older revisions automatically.
>
Exactly. My point wasn't that it makes economic sense to keep all revisions
(it doesn't, as you pointed out) but rather that users don't even /want/ to
keep all revisions. However, by contrast, keeping specific revisions (marked
by users) is both cheep and useful.

You have a good point that it also makes sense to keep recent revisions.
People can use those in case they accidentally delete/change something they
need.

Natan