Re: Enlighten me about jigdo ..
On Fri, 14 Nov 2003, Delian Krustev wrote:
> On Friday 14 November 2003 12:41, Richard Atterer wrote:
> > An rsync-based scheme (whose design inspired that of jigdo) was used in the
> > old days, the "pseudo image kit" (PIK). The use of rsync turned out to be
> > problematic (too much load on the server), so one of the aims of jigdo was
> > to get rid of rsync. All in all, the PIK worked well, but it didn't scale
> > to large numbers of parallel downloads.
> This is a big step backward. Debian has 300 mirrors and push mirroring
> already running. Loadbalancing should not be problematic in that case.
> If a particular server gets too busy it might limit the number of concurrent
> connections. Priority connections might also be considered(e.g. always
> allow connection from other mirrors while keep the regular downloaders number
> in certain amount). And the cpu power certainly gets cheaper faster than the
> bandwith ..
> Something more. It's proven to work. Look at the rsync servers at let's say
> mirrors.kernel.org or planetmirror.com.
The load that PIK caused was that it did an image that was close to the
official one (thus "pseudo image") that needed to be rsynced against the
real image. The issue was not the load on the debian mirrors but on the
debian iso mirrors that kept the real isos available for rsyncing. This
rsync ate a lot of cputime.
But the real issue is the one later on. Anyone can build "a debian cd",
but what people want is "the official debian cd" and that has to be an
exact copy of the officially generated and tested one.