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In a system, large online transaction processing (OLTP) jobs run during the daytime that require a large database buffer cache. In the night, the system supports batch jobs that require a higher value to be set for the large pool. You must simultaneously configure the memory components to accommodate the peak requirement.
What would you do to automate this configuration for the memory components with change in mode of working?
A. Set the SGA_TARGET initialization parameter to zero.
B. Set the PRE_PAGE_SGA initialization parameter to TRUE.
C. Set the MEMORY_MAX_TARGET initialization parameter to zero.
D. Set the SGA_TARGET initialization parameter to a nonzero value

因为白天需要大的 BUFFER CACHE,晚上需要大的 LARGE POOL,所以可以启动 ASMM 管理。启动 ASMM,需要:
1.除了 sga_target,sga_max_size,lock_sga,pre_page_sga 需要静态调整外,其他都可以动态调整
2.启用方法是需要将 sga_target 设置为非 0,同时将 statistics_level 设置为 typical 或者 all
3.如果使用了自动共享内存管理,下面这些缓存区就不需要在进行设置了,他们会自动设置为 0
i.db_cache_size
ii.shared_pool_size
iii.large_pool_size
iv.java_pool_size
v.streams_pool
4.尽管使用了 assm,还是可以设置缓存区大小的,设置后表示的是该缓存区的下限值,即 orale 任何时候该缓存区都应该不小于这个值,至少预留这么大的空间

原文地址:https://www.cnblogs.com/Babylon/p/7998854.html