Oracle 参数 WORKAREA_SIZE_POLICY 官方解释，作用，如何配置最优化建议
本站中文解释
WORKAREA_SIZE_POLICY参数是用来控制系统作业空间（System Working Area）大小的参数。System Working Area影响sql执行过程中的性能。该参数一般取值选择manual，automatic，auto，或者adaptive。manual和auto参数是Oracle 11g之前使用的参数，只能静态设置大小，而automatic和adaptive参数则可动态改变空间大小以针对各种情景采用最佳策略。所以建议使用automatic或者adaptive参数，来指定System Working Area的大小。
正确的设置方法是：
Alter system set workarea_size_policy=automatic;
Alter system set workarea_size_policy=adaptive;
commit;
官方英文解释
WORKAREA_SIZE_POLICY specifies the policy for sizing work areas. This parameter controls the mode in which working areas are tuned.
| Property | Description |
|---|---|
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Parameter type |
String |
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Syntax |
|
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Default value |
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Modifiable |
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Modifiable in a PDB |
Yes |
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Basic |
No |
Values
You can specify the following values for WORKAREA_SIZE_POLICY:
-
AUTOWhen
AUTOis specified, work areas used by memory-intensive operators are sized automatically, based on the PGA memory used by the system, the target PGA memory set inPGA_AGGREGATE_TARGET, and the requirement of each individual operator. -
MANUALWhen
MANUALis specified, the sizing of work areas is manual and based on the values of the *_AREA_SIZEparameter corresponding to the operation (for example, a sort usesSORT_AREA_SIZE). SpecifyingMANUALmay result in sub-optimal performance and poor PGA memory utilization.
See Also:
Oracle Database
Performance Tuning Guide for additional information on setting this parameter
