Shared Memory Problems

Hi, We have been having strange problems with Informix. We are using Informix 7.2 DS UC and we are running SVR4 OS on an SMP5400 (5 processor, 1.4 TAKE 26) Unix box. System memory is 128MB. Could somebody help us out ? Problem List : ___________________________________________________________ #1.Online runs for about 3 hrs (roughly) and then the online.log says "shmat(ENOMEM) check system MAXMEM" We found out that Informix allocates about 8000 KB in Shared Memory when we start it up.This probably is because the Non Res. SegSize in the Shared Memory Parameters screen was set to 8000KB.We reduced this to 200KB. We also the changed the Add SegSize from 8192KB to 1024KB. After doing this Informix on startup allocated 200KB for Non Res. SegSize and then started dynamically allocating shared memory 1024KB at a time. This went on for about 10 new Shared Memory segments, after which again memory allocation failed and now it said check system SHMSEG value. What we do not understand is, Informix keeps adding new shared memory segments and after a while says check system MAXMEM ? This is irrespective of any configuration we try. At some point or the other memory allocation fails. Ours is a Stored Procedure Intensive application and the memory allocation fails more frequently when we execute some large stored procedures.Also, we noted addition of new shared memory segments are dependent on how often we use our stored procedures. Is there a parameter to allocate memory and tune the usage of these stored procedures ? Is there anything wrong with our configuration ? Do we need any extra Informix patch for the SVR4 version? Do we not have enough system resources out here ? Once Informix could not even shutdown properly when we got the above error message and it kept writing " 16:00:43 Assert Failed: Condition Failed (Bad memory pointer 0x0), In (mt_shm_free) 16:00:43 Who: Session(18, informix@msp6k550, 28739, 0) Thread(43, sqlexec, 0, 1) 16:00:43 Action: Please notify Informix Technical Support. 16:00:43 See Also: /tmp/af.2b1c41 " infinitely in the online.log. So we had to kill informix processes manually. ___________________________________________________________ #2.When we try to start up Informix after shutting down mostly it fails saying " 16:13:30 Event alarms enabled. ALARMPROG = '/opt/informix/log_full.sh' 16:13:31 DR: DRAUTO is 0 (Off) 16:13:31 listener-thread: err = -25572: Network driver cannot bind a name to the port. 16:13:31 Attempting to bring listener thread down 16:13:32 PANIC: Attempting to bring system down" We figured that the port was not freed when we shut Informix down and if we waited for sometime Informix gets started up again. If it is a transient condition why does Informix try to PANIC and bring the entire system down? ___________________________________________________________ #3. Whenever we issue a "system " command in a stored procedure and the system command fails the stored procedure raises an exception. The Informix documentation says the ISAM code contains the exit code of the system command executed but we found the ISAM code is always "-172". And finderr tells us that this is an Informix internal error. --COPY OF OUR MTUNE FILE * ident "$Id: mtune,v 1.50 96/01/31 14:28:08 grouper!cth Exp $" * * Copyright (c) 1990, 1991 UNIX System Laboratories, Inc. * Copyright (c) 1984, 1986, 1987, 1988, 1989, 1990 AT&T * All Rights Reserved * * THIS IS UNPUBLISHED PROPRIETARY SOURCE CODE OF * UNIX System Laboratories, Inc. * The copyright notice above does not evidence any * actual or intended publication of such source code. * * Copyright (c) 1987, 1988 Microsoft Corporation * All Rights Reserved * * This Module contains Proprietary Information of Microsoft * Corporation and should be treated as Confidential. * * Copyright (c) 1987, 1988 Microsoft Corporation * All Rights Reserved * * This Module contains Proprietary Information of Microsoft * Corporation and should be treated as Confidential. * *ident "@(#)master:mtune 1.3.5.7" * * Some of the parameters listed in this file are dynamically * configured by the system and hence changing those parameters * in this file does not affect the performance of the system. * They are listed here strictly for backward compatibility reasons. * Please refer to the System Administration Guide for more details. * * FORMAT... * NAME DEFAULT MIN MAX * * General Kernel Parameters ------------------ * TRACESZ 8192 4096 8192 NCPU 10 1 32 NCALL 60 30 32767 NFILE 150 100 800 NMOUNT 25 25 25 NPROC 400 50 2000 NREGION 210 210 350 NCLIST 120 1 400 MAXUP 60 15 32767 NOFILES 60 20 800 NHBUF 128 32 1024 NPBUF 20 20 400 NAUTOUP 60 0 1200 FDFLUSHR 1 1 1 BDFLUSHR 1 1 1 NSLEEPQ 59 41 1013 MAXPMEM 0 0 1048576 SHLBMAX 3 2 6 FLCKREC 300 100 2000 PUTBUFSZ 4000 2000 20000 MAXSLICE 100 25 100 ULIMIT 3072 2048 12288 SPTMAP 2000 1000 30000 PIOMAP 50 50 50 PIOMAXSZ 64 4 64 MAXMINOR 32768 255 0x3ffff NGROUPS_MAX 16 1 16 NBUF 100 100 3000 BUFHWM 0 0 32767 ARG_MAX 10240 1024 51200 RSTCHOWN 0 0 1 OEMREBOOT 0 0 1 * * File System Parameters --------------- * NINODE 512 100 1300 NS5INODE 500 100 3400 UFSNINODE 600 100 6200 NDQUOT 200 100 400 NRNODE 300 100 1300 S52KNBUF 100 100 400 S52KNHBUF 32 32 256 * * Paged Pipe Buffers Per Process ----------------- * NPBPERPROC -1 -1 5 * * Paging Parameters ----------------- * VHNDFRAC 16 8 32 AGEINTERVAL 9 2 100 MINPAGEFREE 25 25 50 GPGSLO 25 0 25 GPGSHI 40 1 40 GPGSMSK 0x00000420 0x00000420 0x00000420 MAXSC 1 1 1 MAXFC 1 1 1 MAXUMEM 2560 2560 32768 MINARMEM 35 25 40 MINASMEM 35 25 40 MINAKMEM 16 4 64 MINHIDUSTK 4 4 32 MINUSTKGAP 2 2 32 PAGES_UNLOCK 200 200 200 * * STREAMS Parameters ---------------- * NSTRPUSH 9 9 10 STRMSGSZ 0 0 32767 STRCTLSZ 1024 1024 1024 STRTHRESH 0 0 0x1000000 NLOG 10 3 16 NUMSP 32 5 50 NUMTIM 128 1 512 NUMTRW 64 1 512 NUMSAD 8 1 16 NSTRPHASH 64 16 512 NAUTOPUSH 32 32 32 * * Message Parameters --------------- MSGMAP 200 10 32767 MSGMAX 2048 512 32768 MSGMNB 0x8000 4096 0x80000 MSGMNI 50 2 32767 MSGSSZ 16 8 32767 MSGTQL 256 40 32767 MSGSEG 4096 1024 32767 * Semaphore Parameters ------------- SEMMAP 25 10 32767 SEMMNI 25 10 32767 SEMMNS 60 60 32767 SEMMNU 30 30 32767 SEMMSL 25 25 32767 SEMOPM 10 10 32767 SEMUME 10 10 32767 SEMVMX 32767 32767 32767 SEMAEM 16384 16384 16384 * * Shared Memory Parameters ---------- SHMMAX 524288 131072 2147483136 SHMMIN 1 1 1 SHMMNI 10 10 1000 SHMSEG 10 6 300 SHMALL 0x20000 256 0x80000