Orace SQL调优系列之ADDM报告简介

浅浅的花香味﹌ 2021-09-19 01:00 416阅读 0赞

我写的SQL调优专栏：https://blog.csdn.net/u014427391/article/category/8679315

整体分析调优工具

*  AWR：关注数据库的整体性能的报告；
 *  ASH：数据库中的等待事件与哪些SQL具体对应的报告；
 *  ADDM：oracle给出的一些建议
 *  AWRDD：Oracle针对不同时段的性能对比报告
 *  AWRSQRPT：oracle获取统计信息与执行计划

不同场景对应工具

局部分析调优工具：

*  explain plan for
 *  set autotrace on
 *  statistics\_level=all
 *  直接通过sql\_id获取
 *  10046 trace
 *  awrrpt.sql

整体性能工具要点

*  AWR关注点：load profile、efficiency percentages、top 5 time events、SQL Statistics、segment\_statistics
 *  ASH关注点：等待事件与sql完美结合
 *  ADDM：各种建议与对应SQL
 *  AWRDD：不同时期 load profile的比较、不同时期等待事件的比较、不同时期TOP SQL的比较
 *  AWRSQRPT：获取与关注点(统计信息与执行计划)

select output from table (dbms_workload_repository.awr_report_html(v_dbid,v_instance_number,v_min_snap_id,v_max_snap_id));

相关查询试图：

*  v$session (当前正在发生)
 *  v$session\_wait(当前正在等待)
 *  v$session\_wait\_history (会话最近的10次等待事件)
 *  v$active\_session\_history (内存中的ASH采集信息，理论为1小时)
 *  wrh$\_active\_session\_history (写入AWR库中的ASH信息，理论为1小时以上)
 *  dba\_hist\_active\_sess\_history (根据wrh$\_active\_session\_history生成的视图)

对于局部的，比如某个页面列表sql，我们可以使用Oracle的执行计划进行sql调优，但是对于整个系统来说，你可以知道哪些sql比较耗时？当然可以通过查Oracle的共享池得到，不过Oracle系统本身就提供了几种性能分析报告，比如AWR、ASH、ADDM、AWRDD等等报告，本博客介绍一下ADDM性能分析报告

> ADDM全称是Automatic Database Diagnostic Monitor，是Oracle一个实现性能自我诊断的最佳利器。它依赖于AWR，也就是说ADDM要诊断，必要要有诊断的依据。在Oracle中，这个诊断依据就是Oracle AWR，因为Oracle AWR会定期的收集整个数据库在运行期间的性能统计数据。

## 一、ADDM报告生成 ##

继之前AWR、ASH方面的博客之后，https://smilenicky.blog.csdn.net/article/details/89414432，https://smilenicky.blog.csdn.net/article/details/89419185，我再写一篇ADDM方面的博客：

### 1.1 工具选择 ###

对于Oracle数据库可以使用sqlplus或者plsql developer客户端软件  
**sqlplus 使用**  
可以使用sqlplus工具登录  
进入数据库

sqlplus / as sysdba

查看用户

show parameter db_name

用登录之后才可以使用  
**plsql developer使用**  
plsql developer也可以使用，登录之后，选择文件(File)->新建(New)->命令窗口(Command Window)  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9zbWlsZW5pY2t5LmJsb2cuY3Nkbi5uZXQ_size_16_color_FFFFFF_t_70]

### 1.2 自动创建快照 ###

开始压测后执行

exec DBMS_WORKLOAD_REPOSITORY.CREATE_SNAPSHOT ();

可以通过dba\_hist\_wr\_control查看当前的配置情况，当前awr为每1小时做一次数据快照，保留时间为8天。

select * from dba_hist_wr_control;

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9zbWlsZW5pY2t5LmJsb2cuY3Nkbi5uZXQ_size_16_color_FFFFFF_t_70 1]  
修改配置，每隔30分钟收集一次，保存1天

execute dbms_workload_repository.modify_snapshot_settings(interval=>30,retention=>14000);

关闭自动收集

SQL>exec dbms_workload_repository.modify_snapshot_settings (interval=>0,retention=>24*60);

### 1.3 手工创建快照 ###

除了自动创建快照，也可以手工创建快照

select dbms_workload_repository.create_snapshot() from dual;

### 1.4 ADDM报告生成 ###

对于sqlplus客户端的可以使用

@?/rdbms/admin/addmrpt.sql

对于plsql客户端，我用绝对路径去执行，@?的命令找不到文件  
这个要根据自己的Oracle安装路径去修改，例如：

@D:/oracle/product/11.1.0/db_1/RDBMS/ADMIN/addmrpt.sql

（1）快照开始id

Enter value for begin\_snap:418

要根据日志打印的快照id范围来填，所以我可以填写：418

（2）快照结束id

Enter value for end\_snap:420

要根据日志打印的快照id范围来填，所以我可以填写：420

（3）ADDM报告名称

Enter value for report\_name

填写ADDM报告的名称，我可以填写addm\_20190421.html，然后在打印的日志里有文件保存的路径：，比如：D:\\oracle\\product\\11.2.0\\dbhome\_1\\RDBMS\\ADMIN\\addm.html

SQL> @D:/oracle/product/11.2.0/dbhome_1/RDBMS/ADMIN/addmrpt.sql
    Current Instance
    ~~~~~~~~~~~~~~~~
          DBID DB_NAME      INST_ INST_NAME
    ---------- ------------ ----- ------------
    1525762377 ORCL             1 orcl
    Cannot SET TRIMSPOOL
    Cannot SET UNDERLINE
    Instances in this Workload Repository schema
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    DBBID        INSTT DBB_NAME     INSTT_NAME   HOST
    ------------ ----- ------------ ------------ ------------
    * 1525762377     1 ORCL         orcl         PC-201508171
                                                 906
    Using 1525762377 for database Id
    Using 1 for instance number
    PL/SQL procedure successfully completed
    dbid
    ---------
    1525762377
    inst_num
    ---------
    1
    PL/SQL procedure successfully completed
    inst_num
    ---------
    1
    dbid
    ---------
    1525762377
    max_snap_time
    ---------
    18/04/2019
    Specify the number of days of snapshots to choose from
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    Entering the number of days (n) will result in the most recent
    (n) days of snapshots being listed.  Pressing <return> without
    specifying a number lists all completed snapshots.
    Listing the last 3 days of Completed Snapshots 
    INST_NAME    DB_NAME       SNAP_ID SNAPDAT            LV
    ------------ ------------ -------- ------------------ --
    orcl         ORCL              417 16 Apr 2019 00:00   1
    orcl         ORCL              418 16 Apr 2019 19:48   1
    orcl         ORCL              419 16 Apr 2019 21:00   1
    orcl         ORCL              420 16 Apr 2019 22:00   1
    orcl         ORCL              421 16 Apr 2019 23:00   1
    orcl         ORCL              422 17 Apr 2019 21:20   1
    orcl         ORCL              423 17 Apr 2019 22:00   1
    orcl         ORCL              424 17 Apr 2019 23:00   1
    orcl         ORCL              425 18 Apr 2019 00:00   1
    orcl         ORCL              426 18 Apr 2019 21:26   1
    orcl         ORCL              427 18 Apr 2019 22:00   1
    11 rows selected
    dbid
    ---------
    1525762377
    inst_num
    ---------
    1
    max_snap_time
    ---------
    18/04/2019
    Specify the Begin and End Snapshot Ids
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    Begin Snapshot Id specified: 418
    End   Snapshot Id specified: 420
    PL/SQL procedure successfully completed
    bid
    ---------
    418
    eid
    ---------
    420
    PL/SQL procedure successfully completed
    inst_num
    ---------
    1
    dbid
    ---------
    1525762377
    bid
    ---------
    418
    eid
    ---------
    420
    Cannot SET TRIMSPOOL
    Cannot SET UNDERLINE
    Specify the Report Name
    ~~~~~~~~~~~~~~~~~~~~~~~
    The default report file name is addmrpt_1_418_420.txt.  To use this name,
    press <return> to continue, otherwise enter an alternative.
    Using the report name addm.html 
    Running the ADDM analysis on the specified pair of snapshots ...
    bid
    ---------
    418
    eid
    ---------
    420
    inst_num
    ---------
    1
    dbid
    ---------
    1525762377
    task_name
    ---------
    TASK_953
    Generating the ADDM report for this analysis ...
    Started spooling to D:\oracle\product\11.2.0\dbhome_1\RDBMS\ADMIN\addm.html
              ADDM Report for Task 'TASK_953'
              -------------------------------
    Analysis Period
    ---------------
    AWR snapshot range from 418 to 420.
    Time period starts at 16-APR-19 07.48.09 PM
    Time period ends at 16-APR-19 10.00.20 PM
    Analysis Target
    ---------------
    Database 'ORCL' with DB ID 1525762377.
    Database version 11.2.0.1.0.
    ADDM performed an analysis of instance orcl, numbered 1 and hosted at
    PC-201508171906.
    Activity During the Analysis Period
    -----------------------------------
    Total database time was 57 seconds.
    The average number of active sessions was .01.
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    There are no findings to report.
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
              Additional Information
              ----------------------
    Miscellaneous Information
    -------------------------
    There was no significant database activity to run the ADDM.
    The database's maintenance windows were active during 99% of the analysis
    period.
    task_name
    ---------
    TASK_953
    Stopped spooling to D:\oracle\product\11.2.0\dbhome_1\RDBMS\ADMIN\addm.html
    End of Report
    Report written to addm.html.

## 二、ADDM报告性能分析 ##

ADDM性能报告是从数据库的整体配置和局部SQL方面给出建议，阅读时候按FINDING1，FINDING2，…，的顺序阅读就好  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9zbWlsZW5pY2t5LmJsb2cuY3Nkbi5uZXQ_size_16_color_FFFFFF_t_70 2]

下面的图来自《收获，不止SQL优化》一书：  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9zbWlsZW5pY2t5LmJsb2cuY3Nkbi5uZXQ_size_16_color_FFFFFF_t_70 3]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9zbWlsZW5pY2t5LmJsb2cuY3Nkbi5uZXQ_size_16_color_FFFFFF_t_70]: /images/20210812/2a50a9a9c04e44b58e67b137c4666b86.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9zbWlsZW5pY2t5LmJsb2cuY3Nkbi5uZXQ_size_16_color_FFFFFF_t_70 1]: /images/20210812/21a2bf9c574244998e0cf9e1830b96d0.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9zbWlsZW5pY2t5LmJsb2cuY3Nkbi5uZXQ_size_16_color_FFFFFF_t_70 2]: /images/20210812/e8d13a5c2b08446895852aeeffa40558.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9zbWlsZW5pY2t5LmJsb2cuY3Nkbi5uZXQ_size_16_color_FFFFFF_t_70 3]: /images/20210812/94754a402fe042a9992cd858af032131.png