今天检查我的10g的数据库，发现其中两台的dmesg：
application bug: sqlplus(26693) has SIGCHLD set to SIG_IGN but calls wait().
(see the NOTES section of 'man 2 wait'). Workaround activated.

在metalink上查了半天：
提到这个BUG：
Bug 号 3985530
已归档 01-NOV-2004 已更新 10-NOV-2004
产品 SQL*Plus 产品版本  10.1.0.2
平台 Linux x86 平台版本 3.0
数据库版本 10.1.0.2 影响平台  Port-Specific
优先级 Severe Loss of Service 状态 Duplicate Bug. To Filer
基本 Bug 3662585 修复产品版本 无数据

问题陈述:

HOST COMMAND FROM SQL*PLUS OUTPUTS "SIGCHLD SET TO SIG_IGN BUT CALLS WAIT()"
--------------------------------------------------------------------------------

***
11/01/04 10:50 pm
***
TAR:
====
. .
PROBLEM:
==========
From SQL*Plus, when executing "host" command, next messages appear in messages (/var/log/messages) . 
------------------------------------------------------------------------ 
Nov2 13:41:17 jpdel1380 kernel:application bug: sqlplus(14197) has                                
SIGCHLD set to SIG_IGN but calls wait(). 
Nov2 13:41:17 jpdel1380 kernel:(see the NOTES section of 'man 2 wait').                                
Workaround activated. 
------------------------------------------------------------------------
. .
DIAGNOSTIC ANALYSIS: 
======================
We can reproduce this problem on only Linux platform and SQL*Plus 10.1.0.
And this problem doesn't reproduce on other platform or SQL*Plus version. .
Same problem is reported at BUG#3662585.
But this bug is not fixed by waiting for the fix of BUG#3801874.
BUG#3801874 is status 11 now and not fixed. . .
WORKAROUND: 
============
n/a
. .
RELATED BUGS: 
===============
BUG#3662585 . .
REPRODUCIBILITY: 
==================
this problem reproduces on only Linux and SQL*Plus 10.1.0. . .
TEST CASE: 
============
please execute next command from SQL*Plus .
SQL> host echo AAA
. .

这是在我的日志文件中出现的错误提示：
Mar 17 11:04:23 bj kernel: application bug: sqlplus(23819) has SIGCHLD set to SIG_IGN but calls wait().
Mar 17 11:04:23 bj kernel: (see the NOTES section of 'man 2 wait'). Workaround activated.

STACK TRACE: 
==============
n/a
. .
SUPPORTING INFORMATION: 
=========================
My ct keeps watching "/var/log/messages" and checking whether OS problem occures or not.
So unnecesary messages appearing in "/var/log/messages" is a problem for their system. . .
24 HOUR CONTACT INFORMATION FOR P1 BUGS: 
=========================================
n/a
. .
DIAL-IN INFORMATION: 
======================
n/a
. .
IMPACT DATE: 
============
n/a
*** 11/02/04 08:55 pm ***
*** 11/10/04 04:25 pm *** (CHG: Sta->36 G/P->P)
.

没有相应的补丁可以下载，察看/var/log/messages文件，产生的问题基本都是由于热备份和crontab每天执行的一个调度任务导致的，跟前台的应用没什么关系，暂时还没有影响，关注有没有对应的补丁出现。