1.发现多个ora_j0**进程

     可以发现进程重启非常频繁,大概1分钟重启一次，启动ora_j0**的个数为20个

[prmsvr2:/home/oraeye]ps -ef|grep ora_j0|grep -v grep
oracle 213120 1 0 11:01:55 - 0:00 ora_j019_prmdb2
oracle 282808 1 0 11:01:55 - 0:00 ora_j012_prmdb2
oracle 299178 1 0 11:01:54 - 0:00 ora_j004_prmdb2
oracle 434212 1 0 11:01:55 - 0:00 ora_j014_prmdb2
oracle 475238 1 0 11:01:54 - 0:00 ora_j011_prmdb2
oracle 487562 1 0 11:01:54 - 0:00 ora_j008_prmdb2
oracle 614612 1 0 11:01:55 - 0:00 ora_j017_prmdb2
oracle 717008 1 0 11:01:54 - 0:00 ora_j009_prmdb2
oracle 721012 1 0 11:01:54 - 0:00 ora_j006_prmdb2
oracle 749618 1 0 11:01:54 - 0:00 ora_j007_prmdb2
oracle 770268 1 0 11:01:54 - 0:00 ora_j005_prmdb2
oracle 811114 1 0 11:01:55 - 0:00 ora_j015_prmdb2
oracle 831550 1 0 11:01:55 - 0:00 ora_j016_prmdb2
oracle 847940 1 0 11:01:55 - 0:00 ora_j013_prmdb2
oracle 938076 1 0 11:01:54 - 0:00 ora_j010_prmdb2
oracle 942224 1 0 11:01:54 - 0:00 ora_j002_prmdb2
oracle 974968 1 0 11:01:55 - 0:00 ora_j018_prmdb2
oracle 434602 1 0 11:01:54 - 0:00 ora_j000_prmdb2
oracle 668104 1 0 11:01:54 - 0:00 ora_j003_prmdb2
oracle 983424 1 0 11:01:54 - 0:00 ora_j001_prmdb2 

[prmsvr2:/home/oraeye]ps -ef|grep ora_j0|grep -v grep
oracle 454676 1 1 11:02:56 - 0:00 ora_j012_prmdb2
oracle 696366 1 1 11:02:56 - 0:00 ora_j011_prmdb2
oracle 749628 1 1 11:02:56 - 0:00 ora_j019_prmdb2
oracle 770276 1 1 11:02:56 - 0:00 ora_j017_prmdb2
oracle 794824 1 1 11:02:56 - 0:00 ora_j010_prmdb2
oracle 827464 1 1 11:02:55 - 0:00 ora_j009_prmdb2
oracle 831560 1 1 11:02:56 - 0:00 ora_j016_prmdb2
oracle 847946 1 1 11:02:56 - 0:00 ora_j014_prmdb2
oracle 888972 1 1 11:02:55 - 0:00 ora_j007_prmdb2
oracle 934064 1 1 11:02:55 - 0:00 ora_j008_prmdb2
oracle 938080 1 1 11:02:56 - 0:00 ora_j013_prmdb2
oracle 942232 1 0 11:02:55 - 0:00 ora_j001_prmdb2
oracle 962760 1 1 11:02:55 - 0:00 ora_j006_prmdb2
oracle 434608 1 1 11:02:55 - 0:00 ora_j004_prmdb2
oracle 528810 1 2 11:02:56 - 0:00 ora_j015_prmdb2
oracle 549228 1 1 11:02:55 - 0:00 ora_j005_prmdb2
oracle 668112 1 1 11:02:55 - 0:00 ora_j003_prmdb2
oracle 709090 1 1 11:02:55 - 0:00 ora_j002_prmdb2
oracle 905720 1 2 11:02:56 - 0:00 ora_j018_prmdb2
oracle 971040 1 1 11:02:55 - 0:00 ora_j000_prmdb2 

[prmsvr2:/home/oraeye]ps -ef|grep ora_j0|grep -v grep |wc -l
      20

    2.其他参数

SQL> select * from v$version;

BANNER
----------------------------------------------------------------
Oracle9i Enterprise Edition Release 9.2.0.8.0 - 64bit Production
PL/SQL Release 9.2.0.8.0 - Production
CORE    9.2.0.8.0       Production
TNS for IBM/AIX RISC System/6000: Version 9.2.0.8.0 - Production
NLSRTL Version 9.2.0.8.0 - Production

SQL> show parameter job;

NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
job_queue_processes                  integer     20

SQL> select count(*) from DBA_JOBS_RUNNING;

  COUNT(*)
----------
         0

SQL> SELECT count(*) FROM v$session_wait where event=\'jobq slave wait\';

  COUNT(*)
----------
        20

SQL> col name for a32
SQL> col value for a24
SQL> col description for a70
SQL> select a.ksppinm name,b.ksppstvl value,a.ksppdesc description
  2    from x$ksppi a,x$ksppcv b
  3   where a.inst_id = USERENV (\'Instance\')
  4     and b.inst_id = USERENV (\'Instance\')
  5     and a.indx = b.indx
  6     and upper(a.ksppinm) LIKE upper(\'%¶m%\')
  7  order by name
  8  /
Enter value for param: _JOB_QUEUE_INTERVAL
old   6:    and upper(a.ksppinm) LIKE upper(\'%¶m%\')
new   6:    and upper(a.ksppinm) LIKE upper(\'%_JOB_QUEUE_INTERVAL%\')

NAME                             VALUE
-------------------------------- ------------------------
DESCRIPTION
----------------------------------------------------------------------
_job_queue_interval              5
Wakeup interval in seconds for job queue co-ordinator

    3.对cjq进程做10046

[prmsvr2:/oracle]ps -ef|grep cjq
  oracle  327870       1   0   Feb 10      - 770:39 ora_cjq0_prmdb2
  oracle  929872  794774   0 13:24:59  pts/2  0:00 grep cjq 

SQL> oradebug setospid 327870
Oracle pid: 19, Unix process pid: 327870, image: oracle@prmsvr2 (CJQ0)
SQL> oradebug unlimit
Statement processed.
SQL> oradebug event 10046 trace name context forever, level 12
Statement processed.
SQL>  oradebug event 10046 trace name context off;
Statement processed.
SQL> oradebug tracefile_name
/oracle/app/admin/prmdb/bdump/prmdb2_cjq0_327870.trc

    4.查看cjq的10046文件

     发现大量的process startup等待，而且两次批量运行之间的时间间隔在1分钟左右。

WAIT #0: nam=\'process startup\' ela= 59247 p1=74 p2=0 p3=0
WAIT #0: nam=\'process startup\' ela= 51486 p1=74 p2=1 p3=0
WAIT #0: nam=\'process startup\' ela= 51629 p1=74 p2=2 p3=0
WAIT #0: nam=\'process startup\' ela= 48205 p1=74 p2=3 p3=0
WAIT #0: nam=\'process startup\' ela= 47625 p1=74 p2=4 p3=0
WAIT #0: nam=\'process startup\' ela= 55945 p1=74 p2=5 p3=0
WAIT #0: nam=\'process startup\' ela= 47633 p1=74 p2=6 p3=0
WAIT #0: nam=\'process startup\' ela= 51809 p1=74 p2=7 p3=0
WAIT #0: nam=\'process startup\' ela= 57371 p1=74 p2=8 p3=0
WAIT #0: nam=\'process startup\' ela= 50249 p1=74 p2=9 p3=0
WAIT #0: nam=\'process startup\' ela= 51683 p1=74 p2=10 p3=0
WAIT #0: nam=\'process startup\' ela= 47933 p1=74 p2=11 p3=0
WAIT #0: nam=\'process startup\' ela= 47699 p1=74 p2=12 p3=0
WAIT #0: nam=\'process startup\' ela= 47800 p1=74 p2=13 p3=0
WAIT #0: nam=\'process startup\' ela= 47947 p1=74 p2=14 p3=0
WAIT #0: nam=\'process startup\' ela= 52071 p1=74 p2=15 p3=0
WAIT #0: nam=\'process startup\' ela= 47776 p1=74 p2=16 p3=0
WAIT #0: nam=\'process startup\' ela= 47764 p1=74 p2=17 p3=0
WAIT #0: nam=\'process startup\' ela= 47684 p1=74 p2=18 p3=0
WAIT #0: nam=\'process startup\' ela= 47790 p1=74 p2=19 p3=0

    通过O记的大力帮助,终于找出了该问题的原因:Bug 4339922: CJQ PROCESS WAKE UP JOB QUEUE PROCESSES EVERY 1 MINUTES.(THERE IS NO JOBS).因为9i的版本oracle不再提供新补丁支持,ora_j0**相关进程不停重启不太占用系统和数据库资源,在不能升级数据库的情况下,可以考虑设置job_queue_processes到一个合适值,然后忽略该问题。