Gnus fetches too many headers WAS: Re: Showing Complete Active Threads

[Tassilo Horn <heimdall@uni-koblenz.de>]

Rolleston <Nemo@nullsome.net> writes:

> It attempts to download every header it can from the news server. Try that
> on 'alt.test' and you'll begin to see why (setq gnus-fetch-old-headers t)
> is a bad idea. :)

Ok, I was able to reproduce this. I've set nntp-record-commands to t and
made `g' in Summary Buffer to fetch new articles which resulted in

     infko.general (3)

When I entered this Group Gnus started to fetch several megabytes and
the output in *nntp-log* was

,----[ *nntp-log* after entering infko.general with 3 new articles ]
| 20060309T121041.752 news.uni-koblenz.de GROUP infko.general
| 20060309T121041.926 news.uni-koblenz.de XOVER 1-61172
`----

This newsgroup has medium traffic and I enter it several times a day, so
all except the 3 new articles should have been available...

After the `g' I also had

      comp.emacs (1)

and entering this group resulted in

,----[ *nntp-log* after entering comp.emacs with 1 new article ]
| 20060309T121028.368 news.uni-koblenz.de GROUP comp.emacs
| 20060309T121028.372 news.uni-koblenz.de XOVER 54834-54834
`----

That looks quite ok to me.

So why does Gnus fetch all headers of infko.general but only the needed
headers for comp.emacs?

INFO: I use Gnus with gnus-agent and try to prevent loose threads with

        (setq gnus-fetch-old-headers 'some)

      But the 3 new articles in infko.general don't reference old
      articles which would require the fetching of all headers.

Regards,
Tassilo