Suggestions (how to choose mirrors)

[Roberto Ragusa]

Matt Domsch wrote:
> Fedora has 244 public mirrors listed at the moment, and hundreds more
> private mirrors.  We have no way, nor really any desire, to know in
> real time the load and network capacity of any connection between
> each mirror and each specific user.  Perhaps Akamai does, but that's
> not a service we pay for.

Just an idea: instead of (or in addition to) "blind" planning,
based on net topology, geography, declared bandwith etc.,
yum could use an exploration approach:

1) choose a few good mirrors candidate
2) download one file from each of them (first file from
first mirror, second file from second mirror, ....)
3) gather speed statistics
4) reevaluate best mirrors according to statistics for the
remaining files

If the downloads are sorted by increasing size, you basically
use the small ones to sample the mirrors and make a good choice
for the big ones at the end of the list.

(doing many downloads in parallel would be the real plus,
so the slow and ugly mirror taking 1 minute for the 40kB file
will complete while the good mirrors are serving you the
kernel and openoffice.org)

This would also be automatically optimal for local mirrors.

Note that this is almost how P2P sharing works (just missing
the sub-file granularity).

-- 
   Roberto Ragusa    mail at robertoragusa.it