MEMORY_TARGET

MEMORY_TARGET and MEMORY_MAX_TARGET are two new parameters in Oracle database release 11g. These two parameters determine the use of Automatic Memory Management for an Oracle database. Oracle strongly recommends the use of Automatic Memory Management to manage the memory on your system. By setting these two parameters to non-zero values, Oracle enables Automatic Memory Management, and tunes to the target memory size, redistributing memory as needed between system global area (SGA) and the instance program global area (PGA). As a result, the following parameters are automatically sized:

SGA_TARGET

SGA_MAX_SIZE

DB_CACHE_SIZE

SHARED_POOL_SIZE

LARGE_POOL_SIZE

JAVA_POOL_SIZE

STREAMS_POOL_SIZE

PGA_AGGREGATE_TARGET

However, LOG_BUFFER is not affected by Automatic Memory Management, and still needs to be manually sized. Tuning LOG_BUFFER is discussed later in this section.

Since MEMORY_TARGET specifies the total memory size of SGA and PGA, it should be set to a relatively high value to achieve better performance. Oracle Hyperion Financial Management consolidation and reporting are memory-intensive tasks, and require abundant memory. Considering that 32-bit operating systems have limits on available address space (typically 2 GB or 3 GB), Oracle recommends this parameter to be set to at least 1.2 GB. Generally, higher values are associated with better Oracle database performance, so we would like to set this parameter as high as possible without running out of virtual address space.

Suggested setting: minimum 1.2GB, generally higher than 1.2GB (depending on the environment).

When determining the amount of memory to allocate to the Oracle 11g instance, review this section: How to Calculate the Number of Processes for Oracle Database Release 11g.