ITPub博客

首页 > Linux操作系统 > Linux操作系统 > Oracle TIMED_STATISTICS 参数 说明

Oracle TIMED_STATISTICS 参数 说明

原创 Linux操作系统 作者:roominess 时间:2012-02-01 16:43:42 0 删除 编辑

MOS上有关TIMED_STATISTICS参数说明:

Init.ora Parameter "TIMED_STATISTICS" Reference Note [ID 30824.1]

Health CheckAlert: Consider setting TIMED_STATISTICS and STATISTICS_LEVEL to recommendedlevels [ID 957433.1]

 

 

Version

Parameter

 

Type

Modifiable

11.1.0.7

timed_statistics

BOOLEAN

ALTER SESSION
ALTER SYSTEM (IMMEDIATE)

11.1.0.6

timed_statistics

BOOLEAN

ALTER SESSION
ALTER SYSTEM (IMMEDIATE)

10.2.0.4

timed_statistics

BOOLEAN

ALTER SESSION
ALTER SYSTEM (IMMEDIATE)

10.2.0.3

timed_statistics

BOOLEAN

ALTER SESSION
ALTER SYSTEM (IMMEDIATE)

10.1.0.5

timed_statistics

BOOLEAN

ALTER SESSION
ALTER SYSTEM (IMMEDIATE)

10.1.0.4

timed_statistics

BOOLEAN

ALTER SESSION
ALTER SYSTEM (IMMEDIATE)

9.2.0.8

timed_statistics

BOOLEAN

ALTER SESSION
ALTER SYSTEM (IMMEDIATE)

9.0.1.4

timed_statistics

BOOLEAN

ALTER SESSION
ALTER SYSTEM (IMMEDIATE)

8.1.7.4

timed_statistics

BOOLEAN

ALTER SESSION
ALTER SYSTEM (IMMEDIATE)

 

TIMED_STATISTICSspecifies whether or not statistics related to time are collected. It isimportant to set TIMED_STATISTICS=TRUE for obtaining timing information whichwill help in tuning the database.

--TIMED_STATISTICS 指定是否收集于时间相关的统计信息,当设置为TURE时会获取有关时间的更多信息,从而帮助我们来优化DB.

 

有如下三种方法来设置该参数:

(1)初始化参数

The parameter can be set in theinitialisation file e.g.

timed_statistics= TRUE

 

(2)system 级别:

This parameter can be set at system levele.g.

ALTER SYSTEM SETtimed_statistics = TRUE

 

(3)session 级别:

This parameter can be set at session levele.g.

   ALTER SESSION SET timed_statistics = TRUE

 

 

When TIMED_STATISTICS is enabled statistics are generated for the following:

(1)PARSE, EXEC and FETCH CPU costs intrace files

(2)V$WAITSTAT

(3)V$FILESTAT and V$TEMPSTAT

(4)V$SYSSTAT and V$SESSTAT timedstatistics

 

Statistics affected by enabling TIMED_STATISTICS include

CPU used when call started

CPU used by this session

parse time cpu

parse time elapsed

redo write time

session connect time

 

Wait times arerecorded in V$SESSION_EVENT, V$SYSTEM_EVENT and V$SESSION_WAIT irrespective ofthe setting of TIMED_STATISTICS (9.2.0)

 

关于该参数的默认值,在官网上有关TIMED_STATISTICS 参数的说明:

http://docs.oracle.com/cd/E11882_01/server.112/e25513/initparams255.htm#REFRN10218

 

If STATISTICS_LEVEL is set to TYPICAL or ALL,then true

If STATISTICS_LEVEL is set to BASIC,then false

 

如果STATISTICS_LEVEL 设置为TYPICAL或者ALL,那么TIMED_STATISTICS 则默认为true。 如果STATISTICS_LEVEL设置为BASIC,则TIMED_STATISTICS 默认为false。

 

MOS上对STATISTICS_LEVEL的说明:

STATISTICS_LEVELspecifies the level of collection for the database and operating systemstatistics. The Oracle Database collects these statistics for a variety ofreasons, including making self-management decisions. Setting theSTATISTICS_LEVEL parameter to BASIC disables the collection of many importantstatistics required by Oracle Database features and functionality.STATISTICS_LEVEL=ALL should only be set for diagnostic purposes as required.

 

有关该参数在之前整理的Blog里有说明:

Oracle Statistic 统计信息 小结

http://blog.csdn.net/tianlesoftware/article/details/4668723

来自 “ ITPUB博客 ” ,链接:http://blog.itpub.net/15880878/viewspace-715448/,如需转载,请注明出处,否则将追究法律责任。

请登录后发表评论 登录
全部评论

注册时间:2009-02-24

  • 博文量
    118
  • 访问量
    186659