Database Reference
In-Depth Information
Figure 9-49.
Top Activity view through Real-Time ADDM
The top section appears very similar to Top Activity, but is actually sourced from ASH data.
To start the Real-Time ADDM analysis, you click the Start button, shown in Figure
9-50
.
Figure 9-50.
Real-Time ADDM analysis interface for EM12c
If the database is in a hung state, the status will be shown, notifying of the database's inability to accept connections.
Real-Time ADDM will proceed with verifying credentials, providing connection options to be used, and performing
hang analysis.
The report generated is displayed in six tab views, including the Progress tab, General Findings, Hardware Resources
(detailing any hardware issues that are discovered), Activity (providing analysis of database sessions), Hang Data
(providing information specific to the cause of the database hang), and Statistics (providing details on the analysis report).
The option to save or e-mail the results in HTML format is available at the upper-right corner of the Real-Time
ADDM interface.
ADDM Comparison Report
Often the administrator is faced with performance differences in two time periods, when none should occur. The ability
to perform a cause-to-effect analysis for two ADDM reports is available as part of the ADDM comparison report.
The ADDM comparison report is available by choosing Performance
➤
AWR
➤
Compare Period ADDM for any
database target. After clicking the link, you will be asked to submit information about the begin time and end time for
the timeline in question (see Figure
9-51
). In the lower section, you then choose a base period for comparison from
drop-down options that include the preceding time period, the previous day, or the previous week.
