Consult for Oracle Memory Config

Hi everybody,

I need the consult for Oracle memory config.

Server 2008 R2

Oracle Standard 11.2.0.1

The memory Server is 32GB

Currently my memory config is as follows:

SGA Usage:

PGA Usage

As you can see that:

SGA target is set fixed to 21GB and used 19GB

PGA target is set fixed to 6B and used 312 MB.

Memory Target is set fixed to 28GB

When I check the process oracle in task manager, it consumes 21GB Memory.

Check recommend memory_target

As you can see current memory_target is 26GB, and Oracle recommend I should change to 16GB so that performance is still the same and I can utilize my memory?