informix down

wubreeze

IDS, Version 9.21.UC3， Linux 8.0
前几天系统中一个卷/var出现I/O错误，导致系统down。不得不重启！然后灾难来了。

首先是两个表出现问题，删除后重建，导入数据，然后online.log中此两表的错误消失。

但是checkpoint的时间明显增加，原来是0秒，现在如下：

22:19:00  Fuzzy Checkpoint Completed:  duration was 4 seconds, 886 buffers not flushed.
22:19:00  Checkpoint loguniq 56843, logpos 0x7dd528

22:21:34  Fuzzy Checkpoint Completed:  duration was 5 seconds, 1127 buffers not flushed.
22:21:34  Checkpoint loguniq 56843, logpos 0x97b7b4

22:24:08  Fuzzy Checkpoint Completed:  duration was 4 seconds, 1318 buffers not flushed.
22:24:08  Checkpoint loguniq 56843, logpos 0xaf6230

22:26:45  Fuzzy Checkpoint Completed:  duration was 6 seconds, 1474 buffers not flushed.
22:26:45  Checkpoint loguniq 56843, logpos 0xc4c144

22:29:19  Fuzzy Checkpoint Completed:  duration was 5 seconds, 1607 buffers not flushed.
22:29:21  Checkpoint loguniq 56843, logpos 0xda67f0

而且每天都会down
online.log中相关信息如下：
20:36:22  Assert Failed: No Exception Handler
20:36:22  Informix Dynamic Server 2000 Version 9.21.UC3
20:36:22   Who: Session(2006, domain@www.onlinenic.com, 15396, 824585672)
                Thread(2132, sqlexec, 31236e98, 1)
                File: mtex.c Line: 405
20:36:22   Results: Exception Caught. Type: MT_EX_OS, Context: mem
20:36:22   Action: Please notify Informix Technical Support.
20:36:22  stack trace for pid 12888 written to /tmp/af.c3c1005
20:36:22   See Also: /tmp/af.c3c1005
20:36:24  mtex.c, line 405, thread 2132, proc id 12888, No Exception Handler.
20:36:24  invoke_alarm(): /bin/sh -c '/opt/informix/etc/log_full.sh 5 6 "Internal Subsystem failure: 'MT'" "mtex.c, line 405, thread 2132, proc id 12888, No Exception Handler." '
20:36:24  invoke_alarm(): mt_exec failed, status 256, errno 0
20:36:24  The Master Daemon Died
20:36:24  invoke_alarm(): /bin/sh -c '/opt/informix/etc/log_full.sh 5 6 "Internal Subsystem failure: 'MT'" "The Master Daemon Died" '
20:36:24  invoke_alarm(): mt_exec failed, status 256, errno 0
20:36:24  PANIC: Attempting to bring system down

每隔一小时左右，系统会
Dynamically allocated new virtual shared memory segment (size 4096KB)

这是怎么回事？急需帮忙