hi @ll ...
first, i'm an newbie in informix db's. i hope anyone of you can help me.
at the momentan we get a lot of db crashes nearly every day. now i've copied the online.log out of the informix/opt directory. i think the fault is from that lines on:

11:18:43 Assert Failed: No Exception Handler
11:18:43 IBM Informix Dynamic Server Version 9.30.UC7
11:18:43 Who: Session(0, @, 0, 0)
Thread(6, aio vp 1, 0, 8)
File: mtex.c Line: 431
11:18:43 Results: Exception Caught. Type: MT_EX_OS, Context: mem
11:18:43 Action: Please notify IBM Informix Technical Support.
11:18:43 stack trace for pid 689 written to /tmp/af.3eeeb03
11:18:43 See Also: /tmp/af.3eeeb03, shmem.3eeeb03.0
11:18:45 Assert Failed: No Exception Handler
11:18:45 IBM Informix Dynamic Server Version 9.30.UC7
11:18:45 Who: Session(0, @, 0, 0)
Thread(4, aio vp 0, 0, 6)
File: mtex.c Line: 431
11:18:45 Results: Exception Caught. Type: MT_EX_OS, Context: mem
11:18:45 Action: Please notify IBM Informix Technical Support.
11:18:45 stack trace for pid 685 written to /tmp/af.3eceb05
11:18:45 See Also: /tmp/af.3eceb05, shmem.3eceb05.0
11:18:46 Assert Failed: No Exception Handler
11:18:46 IBM Informix Dynamic Server Version 9.30.UC7
11:18:46 Who: Session(4031, informix@host26, 2620, 461044632)
Thread(4173, sqlexec, 1cba76c8, 1)
File: mtex.c Line: 431
11:18:46 Results: Exception Caught. Type: MT_EX_OS, Context: mem
11:18:46 Action: Please notify IBM Informix Technical Support.
11:18:46 stack trace for pid 680 written to /tmp/af.1435eb06
11:18:46 See Also: /tmp/af.1435eb06, shmem.1435eb06.0
11:18:48 Assert Failed: No Exception Handler
11:18:48 IBM Informix Dynamic Server Version 9.30.UC7
11:18:48 Who: Session(4431, informix@host48, 2764, 461041384)
Thread(4591, sqlexec, 1cb8c858, 3)
File: mtex.c Line: 431
11:18:48 Results: Exception Caught. Type: MT_EX_OS, Context: mem
11:18:48 Action: Please notify IBM Informix Technical Support.
11:18:48 stack trace for pid 682 written to /tmp/af.15d7eb07
11:18:48 See Also: /tmp/af.15d7eb07, shmem.15d7eb07.0
11:18:53 mtex.c, line 431, thread 6, proc id 689, No Exception Handler.
11:18:55 PANIC: Attempting to bring system down
11:18:55 semctl: errno = 22

does anybody knows something about that or has anybody an opinion?
this problem is very important.

with best regards and a lot of thanks
christian

I found this when looking for HDR info, it may be of some help.

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Q: Informix spontaneously goes offline. online.log contains lines like
Assert Failed: Internal Error - Segmentation Violation.

A: This is something you should report to Informix. You may trace the last executed SQL statement to reproduce the problem with the following procedure.


In online.log, look for a line like
Who: Session(<session id>, ...)
e.g.
Who: Session(14, informix@, 227885660)
<session id> is a numeric value indicating the session that executed the statement. In the example the session id is 14.
In online.log, look for a line like
See Also: <file1>, <file2>
e.g.
See Also: /tmp/af.91da2, shmem.91da2.0
<file1> will (also) contain the directory where both files reside (in the example: /tmp), <file2> is the Informix memory dump (in the example: shmem.91da2.0, also residing in /tmp).
Logged on as user 'informix', execute the following statement on the command prompt (NT: start Command Line Utilities).
onstat -g ses <session id> <file2>
e.g.
onstat -g ses 14 /tmp/shmem.91da2.0
The result will be the last executed statement.

---------------------------

Have you looked at the contents of the /tmp/af.15d7eb07 file?