ORACLE 10g AWR报告设置总结

 

1：查看、修改AWR报告快照数据的采样间隔、保存策略

SQL> COL DBID FOR 999999999999

SQL> COL SNAP_INTERVAL FOR A26

SQL> COL RETENTION FOR A26

SQL> COL TOPNSQL FOR A10

SQL> select * from dba_hist_wr_control;

         DBID SNAP_INTERVAL              RETENTION                  TOPNSQL

------------- -------------------------- -------------------------- ----------

   3990839260 +00000 01:00:00.0          +00014 00:00:00.0          DEFAULT

SQL> 

SNAP_INTERVAL=+00000 01:00:00.0 表示采样间隔是1小时

RETENTION=+00014 00:00:00.0 表示采样数据保留期限是14天

如上所示，快照采样间隔为1小时一次，快照数据保留14天。修改AWR的快照采样间隔、保存配置，改为30分钟采集一次快照数据，快照数据库保留7天。如下所示：

SQL> COL DBID FOR 999999999999

SQL> COL SNAP_INTERVAL FOR A26

SQL> COL RETENTION FOR A26

SQL> select * from dba_hist_wr_control;

         DBID SNAP_INTERVAL              RETENTION                  TOPNSQL

------------- -------------------------- -------------------------- ----------

   3990839260 +00000 01:00:00.0          +00014 00:00:00.0          DEFAULT

SQL> exec dbms_workload_repository.modify_snapshot_settings(interval=>30,retention=>7*24*60);

PL/SQL procedure successfully completed.

SQL> select * from dba_hist_wr_control;

         DBID SNAP_INTERVAL              RETENTION                  TOPNSQL

------------- -------------------------- -------------------------- ----------

   3990839260 +00000 00:30:00.0          +00007 00:00:00.0          DEFAULT

SQL> 

 

2：手动创建快照（Snapshots）

 

数据库创建快照（Snapshots）一般是按Schedule定期创建的，默认一般一小时创建一个快照，只有当数据库出现问题的时候，你才需要手工创建一个快照。以获取那个时间段内的相关数据。

SQL> exec dbms_workload_repository.create_snapshot(); 

PL/SQL procedure successfully completed.

手工创建快照后，可以通过dba_hist_snapshot视图查看创建的快照信息。

 

3：手动删除快照（Snapshots）

--不指定DBID，默认当前实例DBID

SQL>  exec dbms_workload_repository.drop_snapshot_range(61263,61274);

PL/SQL procedure successfully completed.

--指定DBID

SQL> exec dbms_workload_repository.drop_snapshot_range(7417,7429,3990839260); 

PL/SQL procedure successfully completed.

4：创建基线（baseline）

一般来说当AWR自动维护快照时，如果定义过baseline，与baseline相关的快照不会被删除，即使是过期的快照，这样就相当于手动保留了一份统计数据的历史信息，DBA可以在适当的时间将其与现有的快照进行对比，以生成相关的统计报表

SQL> COL BASELINE_NAME FOR A32;

SQL> SELECT DBID,BASELINE_NAME,  START_SNAP_ID, END_SNAP_ID FROM DBA_HIST_BASELINE;

no rows selected

SQL> exec dbms_workload_repository.create_baseline(59806,59809,'20160726_07_11');

PL/SQL procedure successfully completed.

SQL> SELECT DBID,BASELINE_NAME,  START_SNAP_ID, END_SNAP_ID FROM DBA_HIST_BASELINE;

      DBID BASELINE_NAME                    START_SNAP_ID END_SNAP_ID

---------- -------------------------------- ------------- -----------

3990839260 20160726_07_11                           59806       59809

SQL> 

修改基线名称

BEGIN

  DBMS_WORKLOAD_REPOSITORY.rename_baseline(

    old_baseline_name => 'old_name',

    new_baseline_name => 'new_name');

END;

/

基线（baseline）是自Oracle 10g开始引入的，不过只包括了一些简单的基线功能，创建一个基线允许保留指定范围内的快照用于性能对比，与AWR保留策略无关，可以使用DBMS_WORKLOAD_REPOSITORY包来管理这个功能，在11g中，它被增强了。新增了许多功能。例如固定基线、移动窗口（Moving Window）基线等

 

5: 删除基线（baseline）

首先查看基线设置,找到对应的baseline_name，然后删除，过程如下所示：

SQL>SELECT * FROM DBA_HIST_BASELINE;

SQL> COL BASELINE_NAME FOR A32;

SQL> SELECT DBID,BASELINE_NAME,  START_SNAP_ID, END_SNAP_ID FROM DBA_HIST_BASELINE;

      DBID BASELINE_NAME                    START_SNAP_ID END_SNAP_ID

---------- -------------------------------- ------------- -----------

2179993557 20110112                                 12980       13004

2179993557 20100616                                  7959        7968

2179993557 20100818                                  9461        9485

2179993557 20101020                                 10964       10988

2179993557 20110119                                 13148       13172

2179993557 20101222                                 12476       12500

2179993557 20100602                                  7624        7632

SQL> exec dbms_workload_repository.drop_baseline('20110112',true);

PL/SQL procedure successfully completed.

删除是如果指定了CASCADE参数为true，对应的snap也会被删除。

 

6: 查看快照记录信息

SELECT * FROM  DBA_HIST_SNAPSHOT ORDER BY 1 DESC ;

SELECT SNAP_ID, DBID, INSTANCE_NUMBER, STARTUP_TIME,

       BEGIN_INTERVAL_TIME, END_INTERVAL_TIME,

       FLUSH_ELAPSED, SNAP_LEVEL, ERROR_COUNT

FROM WRM$_SNAPSHOT

WHERE STATUS = 0;

SELECT * FROM SYS.WRH$_ACTIVE_SESSION_HISTORY

7：导出、导入AWR快照数据

SQL> @?/rdbms/admin/awrextr.sql

SQL> @?/rdbms/admin/awrload.sql

8：删除导入的AWR快照数据。

 

如果要删除导入的awr数据，可以使用下面脚本进行删除。

exec dbms_swrf_internal.unregister_database(dbid);

sql> exec dbms_swrf_internal.unregister_database(3990839260);

dbms_workload_repository：

可以删除本地和其他数据库的快照，可以选择不同的快照来进行删除。

dbms_swrf_internal：

只能对其他数据库的快照来进行操作，会把整个快照unregister掉。

9：生成各种类型的AWR报告

Generating Various Types of AWR Reports

AWR reports can be generated by running various SQL scripts to satisfy various requirements. Each report is available in HTML or TXT format:

·         awrrpt.sql

Displays various statistics for a range of snapshots Ids.

·         awrrpti.sql

Displays statistics for a range of snapshot Ids on a specified database and instance.

·         awrsqrpt.sql

Display statistics of a particular SQL statement for a range of snapshot Ids. Run

this report to inspect or debug the performance of a particular SQL statement.

·         awrsqrpi.sql

Displays statistics of a particular SQL statement for a range of snapshot Ids on a specified SQL.

·         awrddrpt.sql

Compares detailed performance attributes and configuration settings between two selected time periods.

·         awrddrpi.sql

Compares detailed performance attributes and configuration settings between two selected                time periods on a specific database and instance.

查看AWR报告里面某个具体SQL语句的执行计划

SQL> @?/rdbms/admin/awrsqrpt.sql

SQL> @?/rdbms/admin/awrsqrpi.sql

Workload Repository Views

The following workload repository views are available:

·         V$ACTIVE_SESSION_HISTORY - Displays the active session history (ASH) sampled every second.

·         V$METRIC - Displays metric information.

·         V$METRICNAME - Displays the metrics associated with each metric group.

·         V$METRIC_HISTORY - Displays historical metrics.

·         V$METRICGROUP - Displays all metrics groups.

·         DBA_HIST_ACTIVE_SESS_HISTORY - Displays the history contents of the active session history.

·         DBA_HIST_BASELINE - Displays baseline information.

·         DBA_HIST_DATABASE_INSTANCE - Displays database environment information.

·         DBA_HIST_SNAPSHOT - Displays snapshot information.

·         DBA_HIST_SQL_PLAN - Displays SQL execution plans.

·         DBA_HIST_WR_CONTROL - Displays AWR settings.

参考资料：

https://support.oracle.com/epmos/faces/DocumentDisplay?_afrLoop=518649661691529&id=748642.1&_afrWindowMode=0&_adf.ctrl-state=1gfse6hc1_4