* org-gnus.el (org-gnus-nnimap-query-article-no-from-file): New
customization variable.
(org-gnus-nnimap-cached-article-number): New function.
(org-gnus-follow-link): Try to fetch cached article number of
message-id.
Some IMAP servers (e.g. Courier) are slow when searching for a message
by its message id header field. Because article numbers in IMAP
mailboxes are persistent UIDs, we can try to look up the UID of a IMAP
message in Gnus' cache for the mailbox in question and skip the slow
search on the server.
The problem with slow server was reported by Sébastien Vauban and the
patch is based on the work of Tassilo Horn.
The attached patch suppresses a compiler warning in org-gnus.el
* lisp/org-gnus.el:
Suppress compiler warning by declaring outside function
nnimap-retrieve-headers-from-file.
David Maus <dmaus@ictsoc.de> writes:
Hi David,
>>I'm trying to add a workaround to org-gnus.el which should save the
>>slowness of querying the IMAP server by looking up the article number
>>in the group's .overview file. But since I don't have nnimap groups,
>>we have to play some question & answer game. ;-)
>
>>Please apply this patch and set
>>`org-gnus-nnimap-query-article-no-from-file' to t.
>
> The patch does not work: It calls `nnimap-retrieve-headers-from-file'
> without the required arguments (group server)
Argh, stupid me! Here's a corrected patch.
--8<---------------cut here---------------start------------->8---
--8<---------------cut here---------------end--------------->8---
> and the headers are not fetched because
> `nnimap-retrieve-headers-from-file' looks for a NOV cache file, not
> .overview.
Aren't overview file and NOV file synonyms?
Hm, anyway. In the Gnus docs I've found this paragraph:
,----[ (info "(gnus)IMAP") ]
| `nnimap-nov-is-evil'
| Never generate or use a local NOV database. Defaults to the value
| of `gnus-agent'.
|
| Using a NOV database usually makes header fetching much faster,
| but it uses the `UID SEARCH UID' command, which is very slow on
| some servers (notably some versions of Courier). Since the Gnus
| Agent caches the information in the NOV database without using the
| slow command, this variable defaults to true if the Agent is in
| use, and false otherwise.
`----
So maybe we're trying to replace one slow command with another slow
command. Especially, the fact that Courier is explicitly mentioned is a
bit frustrating. Well, let's try it out and see if it helps a bit.
> Alas: I couldn't figure out how to enable NOV cache for my nnimap
> group. Setting `nnimap-nov-is-evil' to nil didn't help.
This variable defaults to the value of `gnus-agent', so I assume the
agent has to be enabled (which is default), and most probably the IMAP
server has to be agentized as well. That can be done in the server
buffer (`^' in *Group*), and then:
,----[ (info "(gnus)Server Agent Commands") ]
| `J a'
| Add the current server to the list of servers covered by the Gnus
| Agent (`gnus-agent-add-server').
`----
Bye,
Tassilo
Use `gnus-summary-article-header' function when in gnus-summary-mode.
This way the article doesn't get displayed unnecessarily. We don't use
this function in the gnus-article-mode because it is not reliable.
Thanks to Leo for this suggestion.
David Maus
Bastien Guerry
Noorul Islam
Tassilo Horn
Carsten Dominik