instance caging – a sample

Instance caging was introduced in 11.2 and desinged to limit the cpu-usage of an instance.

This makes sence when you run several instances on one machine.

In the past, while one instance makes trouble in cpu usage, all others instance got problems as well 😦

Instance caging based on the oracle resource manager.

It makes no sense to throttle a instance permanent down – the system should be well balanced and this feature should be an emergency button.

here’s an example:

sql plan management – how to fix an execution plan

in the past stored outlines were used to fix execution plans
in 11g the next level to control execution plans is implemented
its possible to force the optimizer to use one or more execution plans for a statement, uncontrolled plan changes are disabled.

take a closer look at the following examples – test it!

enable, disable options in 11.2

Starting with 11.2 the installation procedure changed.
There is no more custom installation – all options will be installed.

To check which options are active run
select * from v$option order by parameter;

Stop all instances using this ORACLE_HOME !

cd $ORACLE_HOME/rdbms/lib
make -f ins_rdbms.mk part_on ioracle

SQL>  select * from v$option where upper(parameter) like ‘%PARTI%’;
PARAMETER                                        VALUE
—————————————- —————————————————————-
Partitioning                                           TRUE

make -f ins_rdbms.mk part_off ioracle

SQL>  select * from v$option where upper(parameter) like ‘%PARTI%’;
PARAMETER                                        VALUE
—————————————- —————————————————————-
Partitioning                                           FALSE

These options can be disabled or enabled

                             Enable      Disable
Partitioning                  part_on     part_off
Datamining                    dm_on       dm_off
OLAP                          olap_on     olap_off
Data Vault                    dv_on       dv_off
Real Application Testing      rat_on      rat_off

to disable ALL those options:

make -f ins_rdbms.mk part_off dm_off olap_off dv_off rat_off ioracle

Is it possible to deinstall/remove a specific component from already installed Oracle Database Home using OUI? (Doc ID 888934.1)