oracle Statspack从Oracle8.1.6被引入,马上成为DBA和Oracle专家用来诊断数据库性能的强有力工具。通过Statspack我们可以很容易的
介绍:
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Oracle Statspack从Oracle8.1.6被引入,马上成为DBA和Oracle专家用来诊断数据库性能的强有力工具。通过Statspack我们可以很容易的确定Oracle数据库的瓶颈所有,记录数据库性能状态,也可以使远程技术人员迅速了解的的数据库运行状况。所以,了解和使用Statspack对于DBA来说至关重要。
在Statspack发布之前,我们经常用来诊断数据库的工具是两个脚本utlbstat.sql和utlestat.sql。BSTAT/ESTAT是一个非常简单的性能诊断工具。UTLBSTAT获得开始时很多V$视图的快照,UTLESTST通过先前的快照和当前视图生成一个报表。实际上此报表相当于statspack的两个采样点。
Statspack通过连续的采样,能够给我们提供很重要的趋势分析数据,这是一个巨大的进步。
所以,能够使用Statspack的环境,就尽量不使用BSTAT/ESTAT方式来诊断数据库问题。
(Oracle816以前的版本使用Statspack,需要使用statscbps.sql脚本建立一个V$buffer_pool_statistics视图。可以到oracle网站上下载。)
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原理:
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1,运行oracle自带脚本,生成一系列的统计表。
2,生成快照,采样(运行statspack.snap可生成快照,一般通过自动任务生成快照)
3,,根据快照生成报告
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一,准备
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1,检查部分参数值
--job_queue_process:为了能够建立自动任务,执行数据收集,此参数必须大于0
alter system set job_queue_processess=6;
---timed_statistics,设置为true,使收集的时间信息存储在V$sessstats和V$sysstats等动态性能视图中,但会消耗资源,可以在使用Satspack之前设为true,采样过后,把该参数动态修改为false.
alter system set timed_statistics=true;
2,脚本
使用此功能,需要运行oracle自带脚本,在数据库中生成一系列的表和视图,用于收集各种信息。
脚本位于%oracle_home%\rdbms\admin目录下,oracle816下是一组以stat开头的文件,以后的版本是一组以sp开头的文件。
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二,安装
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1,以sysdba身份登录。
8i可以用internal用户登录:sqlplus internal
9i及以后版本,可以用sys用户以sysdba身份登录:sqlplus / as sysdba
(最好转到脚本所有目录%oracle_home%\rdbms\admin,便于执行脚本)
2,创建表空间,用于保存采样数据
create tablespace perfstat datafile 'e:\hs01\dat\perstat.ora'
size 100m
extent management local;
Statspack的报表数据还是相当占空间的,特别是在多次连续采样的情况下,所以不能太小,最小100M,否则创建对象会失败。
3,运行脚本,安装statspack
Oracle816:%oracle_home%\rdbms\admin\statscre.sql
816以后:%oracle_home%\rdbms\admin\spcreate.sql
--脚本会创建用户perfstat,需要指定此用户密码。
输入 perfstat_password 的值: perfstat
--需要输入用户perfstat使用的表空间:指定新建的表空间即可。
输入 default_tablespace 的值: perfstat
--需要指定用户perfstat使用的临时表空间。
输入 temporary_tablespace 的值: tmp10
--安装成功,可以看到如下信息:
Creating Package STATSPACK...
程序包已创建。
没有错误。
Creating Package Body STATSPACK...
程序包体已创建。
没有错误。
NOTE:
SPCPKG complete. Please check spcpkg.lis for any errors.
--查看错误信息
NT下:
host find "ORA-" *.LIS
host find "err-" *.LIS
Unix下:
grep ORA- *.lis
grep err *.lis
如果出现错误,可以运行脚本删除相关内容:@%oracle_home%\rdbms\admin\spdrop.sql
(注意:也要在sysdba下运行脚本删除相关对象)
然后再重新运行脚本安装。
这个安装过程创建了一系列的表,用于存入采样数据。
查看新建表:
select dt.table_name from dba_tables dt where dt.owner='PERFSTAT'
conn perfstat/perfstat
select table_name from user_tables;
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