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报警日志：
Errors in file /opt/app/oracle/admin/test/bdump/test_pmon_10433.trc:
ORA-00471: DBWR process terminated with error
Fri Jul 27 22:15:08 2012
PMON: terminating instance due to error 471
Fri Jul 27 22:15:08 2012
Errors in file /opt/app/oracle/admin/test/bdump/test_mman_10437.trc:
ORA-00471: DBWR process terminated with error
Fri Jul 27 22:15:08 2012
Errors in file /opt/app/oracle/admin/test/bdump/test_lgwr_10441.trc:
ORA-00471: DBWR process terminated with error
Fri Jul 27 22:15:08 2012
Errors in file /opt/app/oracle/admin/test/bdump/test_psp0_10435.trc:
trac文件：
/opt/app/oracle/admin/test/bdump/test_pmon_10433.trc
Oracle Database 10g Enterprise Edition Release 10.2.0.1.0 - Production
With the Partitioning, OLAP and Data Mining options
ORACLE_HOME = /opt/app/oracle/product/10g
System name:    Linux
Node name:      test
Release:        2.6.9-42.ELsmp
Version:        #1 SMP Wed Jul 12 23:27:17 EDT 2006
Machine:        i686
Instance name: test
Redo thread mounted by this instance: 1
Oracle process number: 2
Unix process pid: 10433, image: oracle@test (PMON)
*** 2012-07-27 22:15:08.296
*** SERVICE NAMESYS$BACKGROUND) 2012-07-27 22:15:08.130
*** SESSION ID170.1) 2012-07-27 22:15:08.130
Background process DBW0 found dead
Oracle pid = 5
OS pid (from detached process) = 10439
OS pid (from process state) = 10439
dtp = 0x200095d8, proc = 0x9f1cf81c
Dump of memory from 0x200095D8 to 0x20009604
200095D0                   0000002D 9F1CF81C          [-.......]