[OpenAFS] mail spool on AFS
Mon, 26 Nov 2001 19:00:24 +0100
On Mon, Nov 26, 2001 at 12:39:47PM -0500, Craig_Everhart@transarc.com wrote:
> Excerpts from mail: 20-Nov-01 Re: [OpenAFS] mail spool on.. Patrick
> LoPresti@cag.lcs (1724*)
> > Too bad you did not take one more step; you could have invented
> > maildirs and avoided the need for any locks at all.
> > See http://cr.yp.to/proto/maildir.html, but my quick summary is as
> > follows:
> > A maildir is a directory hierarchy that looks like this:
> > maildir
> > maildir/tmp
> > maildir/new
> > To deliver a message, the MTA writes it as a new file under tmp, syncs
> > it, and renames it to put it under new. Clients look for messages in
> > new, not tmp, so they never see any message until it has been fully
> > written. This obviates the need for locks.
> Not a bad idea. But our solution, with locks, also prevents collisions
> between multiple simultaneous mail deliveries, as well as the occasional
> multiple simultaneous mail readers, not just single-threaded mail
> delivery vs. single-threaded mail reading.
This is also handled with maildir I think since the unique part of the
maildir filename is usually created using pid,time,hostname etc etc to
make it really unique. I have a maildir-based setup running over AFS
using courier+sqwebmail serving ~3000 users (and rising rapidly ;-).
The neat thing beeing that up to a point I should be able to add more
delivery/reader boxes if I run into performance issues.
What I would like to see is a javamail backend for maildir so I can use
all the nice javabased mail-clients I have found wo going the way over
imap. If anyone has this please drop me a line!