Oracle 11g Performance tuning optimization new features
author : Buleson Consulting
Automatic Memory Tuning
Automatic PGA tuning was introduced in Oracle 9i. Automatic SGA tuning was introduced in Oracle 10g. In 11g, all memory can be tuned automatically by setting one parameter. You literally tell Oracle how much memory it has and it determines how much to use for PGA, SGA and OS Processes. Maximum and minimum thresholds can be set. This is controlled by the Oracle 11g memory_target parameter.
Resource Manager
The 11g Resource Manager can manage I/O, not just CPU. You can set the priority associated with specific files, file types or ASM disk groups.
ADDM
The ADDM in 11g can give advice on the whole RAC (database level), not just at the instance level. Directives have been added to ADDM so it can ignore issues you are not concerned about. For example, if you know you need more memory and are sick of being told it, you can ask ADDM not to report those messages anymore
Faster sorting
Starting in 10gr2 we see an improved sort algorithm , Oracle10gRw introduced a new sort algorithm which is using less memory and CPU resources. A hidden parameter _newsort_enabled = { TRUE |FALSE } governs whether the new sort algorithm will be used.
AWR Baselines
The AWR baselines of 10g have been extended to allow automatic creation of baselines for use in other features. A rolling week baseline is created by default.
Adaptive Metric Baselines
Notification thresholds in 10g were based on a fixed point. In 11g, notification thresholds can be associated with a baseline, so the notification thresholds vary throughout the day in line with the baseline.
