[tpop3d-discuss] Tpop3d over NFS with Maildir: New mail files not immeditately seen?

Rich, WhidbeyNet NOC richs at whidbey.net
Thu, 21 Nov 2002 10:07:21 -0800


Hi Chris,

Thanks for the insight! Syncing the time on the mail NFS servers fixed
the problem, and I can't believe I didn't look at the 3 minute
difference between them. 

Rich
richs@whidbey.net

-----Original Message-----
From: Chris Lightfoot [mailto:chris@ex-parrot.com] 
Sent: Thursday, November 21, 2002 1:36 AM
To: Rich, WhidbeyNet NOC
Cc: tpop3d-discuss@lists.beasts.org
Subject: Re: [tpop3d-discuss] Tpop3d over NFS with Maildir: New mail
files not immeditately seen?


On Wed, Nov 20, 2002 at 05:38:48PM -0800, Rich, WhidbeyNet NOC wrote:
> Hi all,
> 
> We're testing Tpop3d 1.4.2 on a Solaris 8 machine, with standard 
> Maildirs, over NFS, using PAM for authentication. It works great so 
> far, except one problem.
> 
> When new mail arrives in "Maildir/new", either from Qmail, Exim or by 
> manually creating a file, it takes 3 minutes for Tpop3d to recognized 
> it. If you connect to Tpop3d within 3 minutes since the file was 
> created, it reports "You have no messages at all", or, shows however 
> many messages you had before the new mail arrived. Debug just shows:
> 
> maildir_new: scanned maildir /var/mail/username/Maildir (0 messages) 
> in 0.003s

> The problem also does not happen with qmail-pop3d in the same scenario

> (Solaris with Maildirs over NFS, using Qmail and Exim MTAs).

Hmm.

When tpop3d scans a maildir, it doesn't index messages
which were created after it started scanning it. I'm not
sure whether this check is necessary, in fact. A possible problem which
would give the behaviour you observe is if the machine running tpop3d
and the machine running the MDA have a clock difference of three
minutes, but other than that, I'm not sure I can see what's going on
here.

You could try removing the created-before check, with this
patch:

--- maildir.c   13 Nov 2002 20:08:59 -0000      1.13
+++ maildir.c   21 Nov 2002 09:35:46 -0000
@@ -83,7 +83,7 @@
         filename = xmalloc(strlen(subdir) + strlen(d->d_name) + 2);
         sprintf(filename, "%s/%s", subdir, d->d_name);
         if (!filename) return -1;
-        if (stat(filename, &st) == 0 && st.st_mtime < time) {
+        if (stat(filename, &st) == 0) { /* && st.st_mtime < time) { */
             /* These get sorted by mtime later. */
             struct indexpoint pt;
             maildir_make_indexpoint(&pt, filename, st.st_size,
st.st_mtime);


> This issue happens no matter what locking mechanism is 
> enabled/disabled in Tpop3d. Tpop doesn't try to lock Maildirs does it?

Nope.

-- 
``This then, was the apex of Soviet 1960's electronic...
  or at least electric, design-- a safety system that both
  causes, and worsens, disasters.'' (Ami Silberman, on Soviet moon
rockets)