*Databases can now have multiple block sizes.
1.Every database has a "standard" block size specified by db_block_size.
2.The SYSTEM and temporary tablespaces use the standard block size.
3.Application tablespaces can use other block sizes.
4.All partitions of a table or index must use the same block size.
5.The SGA has a separate buffer cache for each block size.
6.One nice use for this feature is transporting tablespaces between databases that use different block sizes.
*You can have Oracle self-tune PGA memory usage instead of setting sort_area_size, hash_area_size, bitmap_merge_area_size, and create_bitmap_area_size manually.
1.Set pga_aggregate_target to the total amount of physical memory available for use by all dedicated server processes.
2.Oracle will then self-tune the *_area_size parameters for all dedicated server connections.
You can still set the *_area_size parameters manually and omit pga_aggregate_target for manual tuning.
*Most parts of the SGA can be dynamically resized and have default sizes.
1.Set the sga_max_size parameter to specify the largest the SGA is allowed to be. This is static. If you don't set sga_max_size, it will default to the initial size of the SGA (meaning that you can dynamically shrink the SGA but not grow it).
2.Set db_cache_size to the size in bytes of the buffer cache for the standard block size. This replaces db_block_buffers, and will default to a setting based on sga_max_size if not specified.
3.Set db_Nk_cache_size to specify the sizes of the buffer caches for alternate block sizes.
4.db_cache_size, db_Nk_cache_size, shared_pool_size, and large_pool_size are all dynamic parameters, meaning you can alter their settings without shutting down the instance.
5.You can still set db_block_buffers and omit sga_max_size, but the SGA and buffer cache size will be static.
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