aix7.1下随机产生僵尸进程，但又会很快消失

那位大虾遇到过oracle11gR2的RAC的grid用户随机产生僵尸进程后又消失了,两个节点都会出现这种情况，不知道是什么原因
我的系统是aix7.1+oracle11gr2_RAC
bash-4.2# oslevel -s
7100-02-02-1316
bash-4.2# su - oracle1
$ sqlplus /  as  sysdba;

SQL*Plus: Release 11.2.0.1.0 Production on Thu Jan 9 14:42:14 2014

Copyright (c) 1982, 2009, Oracle.  All rights reserved.


Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - 64bit Production
With the Partitioning, Real Application Clusters, Automatic Storage Management, OLAP,
Data Mining and Real Application Testing options

SQL>            
bash-4.2# ps -ef|grep defunct
    root 20709526 18088134   0 14:28:08  pts/1  0:00 grep defunct
bash-4.2# ps -ef|grep defunct
    grid 16711856        1   5                  0:00
    grid 20709530        1   5                  0:00
    grid 16712056        1   5                  0:00
    grid 16908662        1   3                  0:00
    root 18154364 18088134   0 14:28:10  pts/1  0:00 grep defunct
bash-4.2# ps -ef|grep defunct
    root 16908664 18088134   0 14:28:13  pts/1  0:00 grep defunct
bash-4.2# ps -ef|grep defunct
    root 18285360 18088134   0 14:28:14  pts/1  0:00 grep defunct收起