关于Size of the Database Buffer Cache与Streams Pool

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Size of the Database Buffer Cache

Oraclesupports multiple block sizes in a database. The standard blocksize is used for the

SYSTEM

tablespace. You specifythe standard block size by setting the initialization parameter

DB_BLOCK_SIZE

. Legitimate values are from 2K to32K.Optionally, you can also set thesize for two additional buffer pools,

KEEP

and

RECYCLE

, by setting

DB_KEEP_CACHE_SIZE

and

DB_RECYCLE_CACHE_SIZE

. These threeparameters are independent of one another.See Also:"MultipleBuffer Pools" for more information about the

KEEP

and

RECYCLE

buffer poolsThe sizes and numbers of non-standard block size buffers arespecified by the following parameters:

DB_2K_CACHE_SIZE
DB_4K_CACHE_SIZE
DB_8K_CACHE_SIZE
DB_16K_CACHE_SIZE
DB_32K_CACHE_SIZE

Note:The

DB_

n

K_CACHE_SIZE

parameterscannot be used to size the cache for the standard block size. Ifthe value of

DB_BLOCK_SIZE

is nK, it isillegal to set

DB_

n

K_CACHE_SIZE

.The size of the cache for the standard block size is alwaysdetermined from the value of

DB_CACHE_SIZE

.