On Mon, Aug 19, 2002 at 11:01:03AM -0400, Feiyu Xie wrote:
> We are using courier imap with Maildir as well, for security, speed, and
> *cough* NFS. I'd consider the Cyrus (which is basicly a Maildir with
> meta-data files for each user) if we don't use NFS for mail storage... Marc,
> could you tell us more about what kind of comparison/experience you had with
> MBX vs. Maildir? This will definitely help people out there...
Well, I had MBX break down in a reasonably sized organization (200 people)
with mailboxes going up to 100MB with 5-10k messages. Not small, but not out
of the ordinary either. You see that in ms exchange every day
uwimap at that stage became quite slow, and by design, expunging messages
from a 5-10k mesg mailbox is excruciatingly slow.
With maildir+ you only have to do one readdir to get a pointer to all the
messages, and the size of each of them.
Deleting one message in the middle is one unlink.
You can get all the new messages or all the read message with one readdir
Mark's paper on directory operations bogging down and being slowed down and
serialized by the kernel is just outdated.
FS that have directories in hashes or btrees can be looked up quite quickly,
and some can apparently support concurrent operations.
Unfortunately, I haven't had the time to setup a system where I can do a
real MBX vs Maildir comparison (it'd take a lot of time to do it fairly for
both sides, and you'd have to redo it with different filesystems)
My other big beef with MBX is that pretty much no mail client directly
supports it without going through an imap server. With Maildir, I can point
mutt at my Maildir directory, and just navigate it, or just use grep or
grepmail to find messages.
(granted, it's not MBX's fault, but if there is no tool support for it
outside of c-client, it's not very useful to me)
Marc
--
"A mouse is a device used to point at the xterm you want to type in" - A.S.R.
Microsoft is to operating systems & security ....
.... what McDonalds is to gourmet cooking
Home page: http://marc.merlins.org/ | Finger [EMAIL PROTECTED] for PGP key
