New performance features in Oracle 11gR2
Now, let's take a look at the new performance tuning features in Oracle 11g R2.
In-Memory Parallel Execution
In-Memory Parallel Execution utilizes aggregated memory in a system to optimize database query performance by reducing or eliminating physical I/O required for parallel operations. Oracle will automatically make a decision as to whether or not an accessed database object, which is using parallel execution, will benefit from being placed into the SGA buffer cache. For Oracle RAC, fragments of the object are mapped into each of the buffer caches on the active instances. These mappings allow Oracle to determine which buffer cache to access specific parts or partitions of the object to respond a granted SQL query. As a result of this new functionality, large parallel operations for RAC are optimized and physical I/O utilization is greatly reduced, as the parallel operation can now be performed in memory.
To use the In-Memory Parallel Execution, you...