Re: nnimap backend performances ?

[Eric Abrahamsen <eric@ericabrahamsen.net>]

On 12/29/15 14:25 PM, myglc2 wrote:
> The following message is a courtesy copy of an article
> that has been posted to gmane.emacs.gnus.general as well.
>
> Eric Abrahamsen <eric@ericabrahamsen.net> writes:
>
>> My understanding is that the nnimap backend was re-written quite
>> significantly two or three years ago (?). At any rate, the people who
>> used the first iteration and were horrified now seem mostly happy with
>> the new version, YMMV. I used to use isync and local dovecot, now use
>> the direct connection, and it doesn't kill me. It isn't great (I'm in
>> China), but it doesn't kill me.
>>
>> eric
>
> So Eric, it sounds like you abandoned ...
>
> https://ericabrahamsen.net/tech/2014/oct/gnus-dovecot-lucene.html

(I didn't see this message show up on the mailing list, but I'm
responding to the list anyway, maybe I just missed it.)

No, I haven't abandoned that setup! Or rather, I've moved halfway away
from it, but I'm going back.

I recently switched my two main email accounts from Google Apps to
self-hosted, and for the moment I'm having Gnus talk directly to the
remote server for the new accounts.

Basically I deleted the two Google Apps accounts, but left the
corresponding imap accounts on my local Dovecot. I didn't want to move
all the old mail into the new accounts, because there's a lot of it.

That means I've got two "legacy" accounts for two addresses, which only
exist locally, and two "new" accounts for the same two addresses, which
only exist on my remote server. At some point I'll explain to my local
Dovecot that these are actually four separate imap stores, and start
syncing the two new accounts locally, as well.

For the time being the two "legacy" accounts are still working just fine
with the local Dovecot arrangement, and I should say are much easier to
search than the new remote accounts. I want to move back mostly because
the connections are still too slow/unstable for my taste. It's not Gnus'
fault.

> ... which I was following & hit the "plain" auth issue you discussed
> ~1yr ago on the isync list.

Ugh, I went through a dark period of confusion and despair for a bit
there, when I was trying to learn too many new things all at the same
time. In fact, I believe the problem was partially solved by upgrading
isync (see the later patch posted to that isync thread). I'm now using
1.3.0, what are you using?

I need to update the blog post: the ~/.mbsyncrc file syntax changed for
the 1.3 version. There's another possibly important difference:

1) /etc/dovecot/dovecot.conf: In the userdb clause, on the "args" line,
I've added at the end:

username_format=%u

2) /etc/dovecot/passwd: The lines that used to look like

eric@ericabrahamsen.net:{PLAIN}passwurd

Now look like

eric@ericabrahamsen.net:{PLAIN}passwurd:eric@ericabrahamsen.net

I think the crux of the problem is that _authentication account_ and
_user account_ are actually separate concerns. Either the previous
version of isync was doing it wrong, or my dovecot config had to be
fixed to separate the two things correctly, or maybe both.

To be honest I've forgotten how it works, a bit, and that's the main
reason I haven't synced my two new accounts to the local dovecot.

I'll try to do that this weekend, and update that blog post! In the
meantime, I hope something in here is helpful to you.

Eric