Re: (gnus-summary-goto-article <message-id>) extremely slow for certain IMAP server

[Tassilo Horn <tassilo@member.fsf.org>]

On Monday 26 July 2010 21:27:13 David Engster wrote:

> > We've edebugged and profiled the gnus code, and the culprit is the
> > function `nnimap-request-article-part'.  When given a message-id instead
> > of an article number, that function will query the IMAP server with
> > `imap-search', and then emacs hangs 5 minutes till the server finally
> > responds.
> >
> > Ok, it's basically the server's fault, 
> 
> Yes. An IMAP server should be able to retrieve articles based on
> message-id's very quickly, since this is a pretty common task.

That's my impression, too.  But at least Sébastiens Courier server seems
to think otherwise.  Maybe it's only some config option the admins need
to enable, who knows...

> > but can't Gnus do any better?  Especially, the mapping message-id to
> > article number is also contained in the .overview file of the group,
> > but it seems that this file is not checked.
> 
> Yes. You could use nnimap-retrieve-headers-from-file and check if you
> find the MID there.

Hm, ok.  How do I get server for a given nnimap+Foo:some.group spec?
`gnus-group-server'?

> > Or can this call to `imap-search' somehow be omitted by optional
> > Gnus features like the gnus registry?
> 
> Probably, but currently the registry does not keep track of the
> article numbers, only of the groups. I guess this could easily be
> added, though?
> 
> But why don't you just save the article number together with the
> message-id in the link?

Because article numbers can change on editable backends, for examply by
moving mail back and forth to other groups.

Bye,
Tassilo