Re: standard apt/yum meta-data format

[Thiemo Seufer <ica2_ts@csv.ica.uni-stuttgart.de>]

Steinar H. Gunderson wrote:
> On Sat, Jul 03, 2004 at 01:43:29PM +0200, Bernd Eckenfels wrote:
> > Well, also the mirrors have less load, if they only need to load the
> > changes, and if they have to serve less data.
> 
> Not neccessarily -- don't assume that "fewer bytes" = "less load". There is a
> non-negligible per-transfer cost involved. (I agree with the other reply in
> this thread that one could store diffs, though, but then you have to make
> sure the clock on the client side is right etc.)

You can work around broken local clocks. Save also the date for the
mirror's Packages file in the index, let apt-get remember it as
last-successful-update, and use it for further updates. If there is
a difference between the index date and the local clock, and no
last-successful-update is available, fetch the full Packages file.

This way, broken systems will cause slightly higher load on the mirror
for their first update. Further updates will be optimized. We can even
completely avoid using the local clock if we want.


Thiemo