Oracle 视图 DBA_HIST_JAVA_POOL_ADVICE 官方解释，作用，如何使用详细说明
本站中文解释
Oracle视图DBA_HIST_JAVA_POOL_ADVICE提供一个快速方法，用于检查当前v$JAVA_POOL视图中JAVA POOL的告警建议和历史建议，以便数据库管理员可以快速识别出在JAVA POOL中可能存在性能问题的潜在原因。
使用DBA_HIST_JAVA_POOL_ADVICE可以跟踪下列信息：
（1）Java Pool大小建议和历史建议：
该视图能够确定JAVA POOL的历史建议和大小建议，从而帮助管理员了解JAVA POOL的性能有何变化，从而有助于他们进一步判断JAVA POOL是否有瓶颈。
（2）Java PoolMisses指标：
可以查看该指标统计值，以确定JAVA POOL是否有空间不足的情况，以及是否需要进行优化。
（3）Java Pool中空余字节的大小：
此视图还可以查看JAVA POOL中空余字节的大小，这有助于确定JAVA POOL是否有内存外流的问题，从而提高JAVA POOL的内存使用效率。
使用方式：
SQL>Select * from DBA_HIST_JAVA_POOL_ADVICE;
官方英文解释
DBA_HIST_JAVA_POOL_ADVICE displays historical information about estimated parse time in the Java pool for different pool sizes.
This view contains snapshots of V$JAVA_POOL_ADVICE.
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Unique snapshot ID |
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Database ID for the snapshot |
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Instance number for the snapshot |
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Java pool size for the estimate (in megabytes) |
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Size factor with respect to the current Java pool size |
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Estimated memory in use by the library cache (in megabytes) |
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Estimated number of library cache memory objects in the Java pool of the specified size |
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Estimated elapsed parse time saved (in seconds), owing to library cache memory objects being found in a Java pool of the specified size. This is the time that would have been spent in reloading the required objects in the Java pool had they been aged out due to insufficient amount of available free memory. |
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Estimated parse time saved factor with respect to the current Java pool size |
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Estimated elapsed time (in seconds) for parsing in a Java pool of the specified size. |
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Estimated load time factor with respect to the current Java pool size |
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Estimated number of times a library cache memory object was found in a Java pool of the specified size |
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The database ID of the PDB for the sampled session |
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T.he ID of the container that
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See Also:
“V$JAVA_POOL_ADVICE”
