ipc doors performance problem ?

[Yann Rouillard]

Hi,

Before switching authentication mechanism to shadow, I ran into some
random authentication problems on a Cyrus Imap/Pop + Sendmail +
Saslauthd setup.with:

saslauthd version 2.1.21
launched with option -a pam
OS: Solaris 9 release 9/04 

During the day, we had some random "generic failure: checkpass failed"
error messages in the logs.

I ran some test by launching the following script a bunch of time:

#!/bin/sh

while true; do
{
sleep 1
echo "USER test"
sleep 1
echo "PASS testpass"
sleep 1
echo "QUIT"
sleep 1
} | telnet localhost 110


The random authentication problems always appears with ipc doors + pam
authentication module.
Switching to ipc unix (with 5 workers) or to shadow authentication
solved the problem (but I suppose shadow is more efficient than pam so
maybe a more important workload would have been needed to trigger the
bug).

Is this a known problem ? The ipc doors system can't scale well to the
workload ?

Yann