Oracle 参数 OBJECT_CACHE_MAX_SIZE_PERCENT 官方解释,作用,如何配置最优化建议

本站中文解释

OBJECT_CACHE_MAX_SIZE_PERCENT参数用于控制元数据对象缓存大小占物理内存总量的比例,如表、索引、视图等,它默认值为0,且只在共享池模式有效。

设置该参数有以下两种方法:

1.使用 ALTER SYSTEM 命令修改 :

ALTER SYSTEM SET OBJECT_CACHE_MAX_SIZE_PERCENT=90;

2.修改$ORACLE_HOME/dbs/init.ora文件:

OBJECT_CACHE_MAX_SIZE_PERCENT=90

建议设置20-50之间,较低的值将保留足够的内存空间以存储足够的元数据对象,而较高的值可增加元数据读取性能,建议根据实际服务器情况进行调整。

官方英文解释

The object cache is a memory block on the client that allows applications to store entire objects and to navigate among them without round trips to the server. OBJECT_CACHE_MAX_SIZE_PERCENT specifies the percentage of the optimal cache size that the session object cache can grow past the optimal size.
Property Description

Parameter type

Integer

Default value

10

Modifiable

ALTER SESSION, ALTER SYSTEM ... DEFERRED

Modifiable in a PDB

Yes

Range of values

0 to operating system-dependent maximum

Basic

No

The maximum size is equal to the optimal size plus the product of this percentage and the optimal size. When the cache size exceeds this maximum size, the system will attempt to shrink the cache to the optimal size.

See Also:

  • “OBJECT_CACHE_OPTIMAL_SIZE” for a description of the object cache

  • Pro*C/C++ Programmer’s
    Guide
    and Oracle Call Interface
    Programmer’s Guide
    for information on precompiler use of the object cache


数据运维技术 » Oracle 参数 OBJECT_CACHE_MAX_SIZE_PERCENT 官方解释,作用,如何配置最优化建议