Oracle数据库诊断案例-redo log日志组处于高激活状态

平台:SunOS 5.8 Generic_108528-23 sun4u sparc SUNW,Ultra-Enterprise

数据库:8.1.5.0.0

症状:响应缓慢，应用请求已经无法返回

登陆数据库,发现redo日志组除current外都处于active状态

oracle:/oracle/oracle8>sqlplus "/ as sysdba"
SQL*Plus: Release 8.1.5.0.0 - Production on Thu Jun 23 18:56:06 2005
(c) Copyright 1999 Oracle Corporation.  All rights reserved.
Connected to:
Oracle8i Enterprise Edition Release 8.1.5.0.0 - Production
With the Partitioning and Java options
PL/SQL Release 8.1.5.0.0 - Production
SQL> select * from v$log;
    GROUP#    THREAD#  SEQUENCE#      BYTES    MEMBERS ARC STATUS           FIRST_CHANGE# FIRST_TIM
---------- ---------- ---------- ---------- ---------- --- ---------------- ------------- ---------
         1          1     520403   31457280          1 NO  ACTIVE              1.3861E+10 23-JUN-05
         2          1     520404   31457280          1 NO  ACTIVE              1.3861E+10 23-JUN-05
         3          1     520405   31457280          1 NO  ACTIVE              1.3861E+10 23-JUN-05
         4          1     520406   31457280          1 NO  CURRENT             1.3861E+10 23-JUN-05
         5          1     520398   31457280          1 NO  ACTIVE              1.3860E+10 23-JUN-05
         6          1     520399   31457280          1 NO  ACTIVE              1.3860E+10 23-JUN-05
         7          1     520400  104857600          1 NO  ACTIVE              1.3860E+10 23-JUN-05
         8          1     520401  104857600          1 NO  ACTIVE              1.3860E+10 23-JUN-05
         9          1     520402  104857600          1 NO  ACTIVE              1.3861E+10 23-JUN-05
9 rows selected.
SQL> /
    GROUP#    THREAD#  SEQUENCE#      BYTES    MEMBERS ARC STATUS           FIRST_CHANGE# FIRST_TIM
---------- ---------- ---------- ---------- ---------- --- ---------------- ------------- ---------
         1          1     520403   31457280          1 NO  ACTIVE              1.3861E+10 23-JUN-05
         2          1     520404   31457280          1 NO  ACTIVE              1.3861E+10 23-JUN-05
         3          1     520405   31457280          1 NO  ACTIVE              1.3861E+10 23-JUN-05
         4          1     520406   31457280          1 NO  CURRENT             1.3861E+10 23-JUN-05
         5          1     520398   31457280          1 NO  ACTIVE              1.3860E+10 23-JUN-05
         6          1     520399   31457280          1 NO  ACTIVE              1.3860E+10 23-JUN-05
         7          1     520400  104857600          1 NO  ACTIVE              1.3860E+10 23-JUN-05
         8          1     520401  104857600          1 NO  ACTIVE              1.3860E+10 23-JUN-05
         9          1     520402  104857600          1 NO  ACTIVE              1.3861E+10 23-JUN-05
9 rows selected.

如果日志都处于active状态，那么显然DBWR的写已经无法跟上log switch触发的检查点。