The amount of memory specified in MEMORY_TARGET is allocated between the SGA and PGA
automatically; when MEMORY_TARGET is set, SGA_TARGET and PGA_AGGREGATE_TARGET
are set to zero and ignored.
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Chapter 8: Database Tuning 255
As the workload in the database changes, the database will alter the cache sizes to reflect the
needs of the application. For example, if there is a heavy batch-processing load at night and a
more intensive online transaction load during the day, the database may alter the cache sizes as
the load changes. These changes occur automatically, without DBA intervention. If you specify a
value for a pool in your initialization parameter file, Oracle will use that as the minimum value
for that pool.
NOTE
DBAs can create KEEP and RECYCLE pools in the buffer cache. KEEP
and RECYCLE pools are not affected by the dynamic cache resizing
and are not part of the DEFAULT buffer pool.
From within OEM, you can see if dynamic memory management is enabled by clicking the
Memory Parameters option; the Automatic Shared Memory Management button can be set to
???Enabled??? or ???Disabled.???
You may wish to selectively ???pin??? packages in the shared pool. Pinning packages in memory
immediately after starting the database will increase the likelihood that a large enough section of
contiguous free space is available in memory. As shown in the following listing, the KEEP procedure
of the DBMS_SHARED_POOL package designates the packages to pin in the shared pool:
execute DBMS_SHARED_POOL.
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