Ok, but according to exim's doc, MBX locking doesnt work over NFS..
Argh.. is there no format that doesnt have some major design flaw?!
I need to support a mixed environment - POP, IMAP, webmail.. I need to
be able to distribute load over multiple servers - which unless someone
has a better idea, means NFS.. I need speed and reliability. So far
nothing seems to fit that bill.
I've looked at Cyrus, but there doesnt seem to be any straightforward
documentation on how to set it up (eg, the installtion instructions say
among other things "Ok, now add a user (sic)".. WITHOUT ANY EXPLANATION
AS TO EXACTLY HOW TO DO THAT.
I beleive we are agreed that standard unix format is the 'lowest common
denominator', and has the worst performance in any situation..
Im about ready to write my own damn daemon, specify my own new format,
and include a 'deliver' like utility to provide delivery from MTA-land.
Too bad all Im good at coding in is bash.. ;)
Here's a question - is anyone familiar with the 'tenex' mailbox format
that Pine (and presumably c-client) uses?
The pine documentation says to create 'mail.txt' in your homedir, and
when pine starts up, it reads new mail out of your standard berk format
mailbox into this tenex format. I have my personal account on my
personal server set to use that, and it seems to work reasonably well.
(I use only pine, however - no pop or imap ever) I'm fairly certain
UW-imap supports that as well.. For distribution this would require both
/var/spool/mail and the home directories to be NFS mounted on all
relevant machines. I have no idea how well (if) the locking mechanism
works over NFS.
On Sat, 31 Mar 2001, Tom Samplonius wrote:
>
> On Fri, 30 Mar 2001, Michael J. Tubby B.Sc. G8TIC wrote:
>
> > I implemented Courier IMAP about 8-9 monts ago and have found it to be
> > excellent. Courier-IMAP beats WU-IMAPD every way you look at it....
> >
> > - Maildir is a much better format for storing messages (fast, efficient,
> > etc)
>
> Most people aren't aware that UW imapd (note: this is not WU!) supports
> more than the default UNIX bezerk format. The default UNIX format is very
> poor, and the uw-imapd supports it for backwards compatibility reasons
> only. The MBX format is recommended.
>
> Second, Maildir has performance weaknesses. The time to open a maildir
> is dependent on the number of messages in the mailbox. An MBX format
> mailbox containing 5000 messages will open faster than a maildir mailbox
> with 5000 messages in it. Cyrus imapd/popd mailboxes would open faster
> yet, because it keeps a header index, and the actual messages would not
> have to touched.
>
> Maildir handles selective message deletion better than MBX. Cyrus
> imapd/popd is just as good as Maildir. Though deleteing all messages
> (common for a POP server) is fastest on MBX.
>
> MBX uses storage more efficiently than Cyrus or MBX, as messages are
> packed together. It also uses less inodes.
>
> Implementing quotas on servers that don't have Unix users setup is
> rather slow on Maildir. MBX is very easy since you just stat() the
> mailbox file. Cyrus is also easy since its message index contains quota
> support. Maildir quota checks require totaling the size of the all
> messages in the mailbox. That is a very slow process, and gets slower as
> the number of messages increase.
>
>
> Tom
>
>
> --
> ## List details at http://www.exim.org/mailman/listinfo/exim-users Exim details at http://www.exim.org/ ##
>
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