Oracle Automatic Memory parameter dependency

Oracle Automatic Memory parameter dependency

The database will only automatically optimize the size of the child components of SGA. The Automatic Optimization of PGA is irrelevant to whether or not to explicitly set the PAG. However, the overall SGA (SGA_TARGET) and PGA (PGA_AGGREGATE_TARGET) are not automatically optimized, that is, they do not automatically increase or contract. If neither SGA_TARGET nor PGA_AGGREGATE_TARGET is set, the current policy is used. PGA is automatically optimized and SGA is not automatically optimized. Parameters of some sub-components (SGA_TARGET) need to be explicitly set ).

If only MEMORY_MAX_TARGET is set, the default value of MEMORY_TARGET is 0 when the initialization text file is used for manual setting. The default Automatic Optimization behavior of SGA and PGA is 10g R2.

If SGA_MAX_SIZE is not set, when MEMORY_MAX_TARGET is set, SGA_MAX_SIZE is set to MEMORY_MAX_TARGET internally (irrelevant to whether SGA_TARGET is set ).
In the initialization parameter text file, if the line MEMORY_MAX_TARGET is omitted and contains the value of MEMORY_TARGET, the database automatically sets MEMORY_MAX_TARGET to the value of MEMORY_TARGET. If the line MEMORY_TARGET is omitted and contains the value of MEMORY_MAX_TARGET, the default value of MEMORY_TARGET is 0. If MEMORY_TARGET does not exceed the value of MEMORY_MAX_TARGET after startup, you can change it to a non-zero value dynamically.