Mail system Suggestions

[Bill Moran]

Mikhail Goriachev <mikhailg at webanoide.org> wrote:

> jan gestre wrote:
> > On 7/22/06, Dave <dmehler26 at woh.rr.com> wrote:
> >> Hi,
> >>     I would recommend dovecot. It's capable of both imap as well as pop if
> >> you later want to add that and can do encrypted versions of those
> >> protocols
> >> as well. Dovecot is also in my opinion much easier to configure and less
> >> resource intensive than other imap servers.
> >>     If i can be of any assistance let me know.
> >> Thanks.
> >> Dave.
> > 
> > i second it, dovecot works great, try it.
> 
> I'm not into starting a flaming session, but dovecot's indexing/caching
> capabilities are the only things that make it fast. Am I right? Well, it
> is also written in C. I came across a few posts[1][2], though they're
> old, saying that everything depends on e-mail clients as well.
> 
> I'm responsible for 2 courier-imap in production and about to start
> working on a new one. This and previous threads regarding dovecot caught
> my attention and it sounds interesting. However, what good is there
> having indexes on IMAP server and on local machine?
> 
> I realised that my Thunderbird keeps record of all my folders and their
> contents. So roughly I've got ~800MB of e-mails on IMAP and 12MB of
> indexes in Thunderbird's profile. Also, apparently Outlook 2003 caches
> absolutely everything. I've seen accounts with 2.9GB worth of e-mails on
> IMAP and generated outlook.pst as big as 950MB. Maybe dovecot's indexing
> features would be great in webmail environments?
> 
> Maybe I just got lost somewhere. Any input would be highly appreciated.

I don't know enought about Dovecot in particular to say whether or not
the speed is _purely_ the result of caching (and being written in C).

But I can state a couple of reasons why the server-side cache helps.
Keep in mind that IMAP is specifically designed as a clieng/server
protocol.  I generally have the same mailbox open from three computers:
my home, my work and my laptop.  When changes are made from one of these,
the other two need to get synchronized.  Like most people, I try to
keep my mails organized into folders that don't get too big, but I still
end up with 1000s of mails in each folder.

Dovecot keeping a cache/index on the server side allows Dovecot to quickly
provide information when the clients want to sync up.  When a mail client
is first started, it needs to do the equivalent of "send me a list of all
the emails in this folder".  If Dovecot needs to scan each and every message,
it can be pretty slow, but if it has an index maintained that it can more
or less just ship as is, that's much faster.  How often these types of
"overall sync" operations occur under normal usage, I don't know.

While I'm not an expert, I believe that Courier maintains indexes as well.

-- 
Bill Moran

You will give me the Ring freely?  In place of the Dark Lord you will set
up a Queen.  And I shall not be dark, but beautiful and terrible as the
Morning and the Night!  Fair as the Sea and the Sun and the Snow upon the
Mountain!  Dreadful as the Storm and the Lightning!  Stronger than the
foundations of the earth.  All shall love me and despair!

        Galadriel