Database Reference
In-Depth Information
Chapter 4
Real-Time Analysis of
Irreproducible Problems
Dynamic performance views provide key information for real-time analysis of performance problems. Because there
are many such views, choosing the right ones and accessing them in the right order is of paramount importance to
efficiently pinpoint a performance problem. To choose the right dynamic performance views, you also have to ask
yourself one key question:
Do I have access to the features provided by the Diagnostics Pack and Tuning Pack options?
The question isn't technical at all. Nevertheless, answering it is necessary because you're allowed to use certain
dynamic performance views, and therefore database features (the key features for real-time analysis are
active
session history
and
real-time monitoring
), only when you have licensed the corresponding option. Be aware that the
Diagnostics Pack option is a prerequisite for the Tuning Pack option. And because all options aren't available with
Standard Edition, Enterprise Edition is a prerequisite as well. For detailed information about licensing, refer to the
Oracle Database Licensing Information
manual.
■
If you don't have the license for either the Diagnostics Pack option or the Tuning Pack option, from version 11.1
onward you should set the
control_management_pack_access
initialization parameter accordingly. In Enterprise Edition,
the default value is
diagnostic+tuning
. That means both options are enabled. Other valid values are
diagnostic
and
none
. The former enables only the Diagnostics Pack option, and the latter, which is the default value in Standard
Edition, disables both options. There are basically two advantages to setting the initialization parameter to the right value.
First, some features are disabled and, as a result, don't cause unnecessary overhead. Second, when using the
Enterprise Manager, the pages that require one of the two options can't be accessed, which means you don't break
your licensing agreement.
Tip
Independently of whether you're able to use the optional features or not, the steps you go through during an
analysis don't change. Let's discuss them with the help of an analysis roadmap.
