Re: Any tricks to speedup nnimap?

[Eric Abrahamsen <eric@ericabrahamsen.net>]

Pankaj Jangid <pankaj.jangid@gmail.com> writes:

> Hi,
>
> I am using Gnus to read news and emails. News is fine. Whenever I open
> an unread article, it opens in a snap. Really fast. Some prefetch
> mechanism is at play. I haven't done anything to speed up news. This is
> default behaviour in my Emacs 26.3
>
> But when inside an nnimap group, it takes time to open an email. I press
> <RET> on any email then it connects to server to fetch. Is it possible
> to prefetch emails? I want the news like fast behaviour in reading
> emails.
>
> I have tried following things:
>
> ;; (1) globally
> (setq gnus-asynchronous t)
> (setq gnus-use-article-prefetch 30) ; this is default

Unfortunately, the nnimap backend doesn't support asynchronous calling,
so this won't work. I can't immediately think of why nnimap couldn't be
made asynchronous, but the work hasn't been done.

> ;; (2) under nnimap server section
> (nnimap-fetch-partial-articles t)

This will only have a noticeable effect if the email has a big
attachment or something on it. If it's just a plain text/HTML email, you
probably won't notice a speedup.

> These (above) two approaches aren't working on emails.
>
> I have read some articles that recommend "mbsync" and "dovecot". But
> that is a dependency on external tools. I would prefer native emacs
> approach if it is possible.

They aren't really external tools -- well, they're external to Emacs,
but Gnus will still behave the same as always. Essentially, going that
route is replicating an IMAP server on your local machine, and having
Gnus access that server rather than the remote one. That might sound
excessive, but actually it works quite well. It is very fast, and has
the advantage that you can still do everything you need to with your
email while you're offline.

Eric