Oracle 视图 V$MEMORY_TARGET_ADVICE 官方解释,作用,如何使用详细说明
本站中文解释
V$MEMORY_TARGET_ADVICE视图显示内存管理的建议参数设置,其中有两个列:
COMPONENT:实例参数组件名称
RECOMMENDATION:根据当前数据库调用推荐的内存参数值。
使用V$MEMORY_TARGET_ADVICE视图,用户可以查看实例参数(如sga_target和pga_aggreate_target)的建议值,以调整当前系统的内存管理。此外,用户可以根据此视图查看正在运行参数设置是否符合实际情况,如果不合适,可以根据它的建议值重新调整参数。
官方英文解释
V$MEMORY_TARGET_ADVICE
provides information about how the MEMORY_TARGET
parameter should be sized based on current sizing and satisfaction metrics.
Column | Datatype | Description |
---|---|---|
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If the If the value of the |
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A multiplier for the current memory size. Possible values are 0.25, 0.5, 0.75, 1, 1.5, 1.75, and 2. This multiplier times the current memory size equals the value of the |
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For current memory size ( |
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For a proposed memory size, ratio of estimated database time to current database time |
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Version number of this recommendation (this snapshot of the |
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The ID of the container to which the data pertains. Possible values include:
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Table 9-2 shows how the information provided in V$MEMORY_TARGET_ADVICE
could be used to improve performance. The data indicates that if current memory size is 380M, and you were to increase it to 760M (2x), the current workload would take 80525 units of DBtime as opposed to 115475 units of DBtime, which is a significant improvement in performance.
Table 9-2 Example of Using V$MEMORY_TARGET_ADVICE
MEMORY_SIZE | MEMORY_SIZE_FACTOR | ESTD_DB_TIME | ESTD_DB_TIME_FACTOR | VERSION |
---|---|---|---|---|
380 |
1 |
115475 |
1 |
3 |
95 |
.25 |
200500 |
1.7 |
3 |
190 |
.5 |
125600 |
1.1 |
3 |
760 |
2 |
80525 |
0.7 |
3 |
See Also:
“MEMORY_TARGET”