RCs for Everyone (was One (more) week slip of Fedora 11 Release)

[Seth Vidal]

On Mon, 1 Jun 2009, Chris Adams wrote:

> Once upon a time, Michael Cronenworth <mike at cchtml.com> said:
>> Sounds like the mirrors should use bitorrent? (then why not just let
>> users use bittorrent) This will be my last random thought today.
>
> Bittorrent is not some magic wand.  The problem is just the volume of
> bits that would have to be pushed out in a short period of time to be
> useful.  To generate 25G+ of data and try to distribute it in a timely
> fashion, Red Hat would have to dedicate large amounts of bandwidth for
> just that purpose.  The bits would have to get from the point the ISOs
> are generated to the public servers to at least some consumers (be they
> mirrors or end-users).
>
> Let's say you wanted to get 25G out (at least to the initial point of
> distribution) in 4 hours.  That's an average line rate of about 14
> megabits per second to distribute them to _one_ other site.  If you have
> just 10 other sites trying to get them simultaneously, you'll need a
> full OC-3 or a fractional gigabit ethernet link.
>
> Also, mirrors aren't going to use Bittorrent to fetch bits because AFAIK
> the automation is not available.  I have scripts wrapped around rsync to
> keep things in sync (and even that still needs some "hand holding" now
> and then).

And it is probably worth reading the analysis of mirrors and torrents 
written by John Hawley

  http://linuxsymposium.org/2008/ols-2008-Proceedings-V1.pdf page 173

-sv