DB_BLOCK_BUFFERS

Property	Description
Parameter type	Integer
Default value	0
Modifiable	No
Range of values	50 to an operating system-specific maximum
Basic	No
Real Application Clusters	Multiple instances can have different values, and you can change the values as needed.

Note:

DB_BLOCK_BUFFERS cannot be combined with the dynamic DB_CACHE_SIZE parameter; combining these parameters in the same parameter file will produce an error.

DB_BLOCK_BUFFERS specifies the number of database buffers in the buffer cache. It is one of several parameters that contribute to the total memory requirements of the SGA of an instance.

This parameter, together with DB_BLOCK_SIZE, determines the total size of the buffer cache. Effective use of the buffer cache can greatly reduce the I/O load on the database. DB_BLOCK_SIZE can be specified only when the database is first created, so you use DB_BLOCK_BUFFERS to control the size of the buffer cache.

Note:

1. Related parameters: DB_BLOCK_LRU_LATCHES, DB_BLOCK_SIZE

2. Query for the current value of the parameter

select name, value, isdefault, isses_modifiable, issys_modifiable,

isinstance_modifiable, isdeprecated, description

from v$parameter where upper(name) = ‘DB_BLOCK_BUFFERS’;

NAME	VALUE	IS DEFAULT	ISSES_ MODIFIABLE	ISSYS_ MODIFIABLE	ISINSTANCE_ MODIFIABLE	IS DEPRECATED	DESCRIPTION
db_block_buffers	0	TRUE	FALSE	FALSE	FALSE	FALSE	Number of database blocks cached in memory

Oracle initializatoin parameters