DATA_TRANSFER_CACHE_SIZE

DATA_TRANSFER_CACHE_SIZE sets the size of the data transfer cache (in bytes) used to receive data blocks (typically from a primary database in an Oracle Data Guard environment) for consumption by an instance during execution of an RMAN RECOVER ... NONLOGGED BLOCK command.

Property	Description
Parameter type	Big integer
Syntax	DATA_TRANSFER_CACHE_SIZE = integer [K | M | G]
Default value	If SGA_TARGET is set, then if DATA_TRANSFER_CACHE_SIZE is not specified, the default size of the data transfer cache is 0 (internally determined by Oracle AI Database). If SGA_TARGET is set and DATA_TRANSFER_CACHE_SIZE is specified, then the user-specified value indicates the minimum value for the data transfer cache. If SGA_TARGET is not set, the data transfer cache will not be available.
Modifiable	ALTER SYSTEM
Modifiable in a PDB	No
Range of values	0 - 512M, rounded up to the next granule size
Basic	No
Oracle RAC	Multiple instances can have different values.

This initialization parameter needs to be set only for databases that do not use Automatic Memory Management and that use the RMAN RECOVER ... NONLOGGED BLOCK command.