Impending Bottlenecks - Timed Statistics
Note: Available for Oracle 10.2 and later.
The Impending Bottleneck Predictions page contains a table of the categories of timed statistics that are likely to contribute to bottlenecks. Use the controls on this page to calculate and display potential bottlenecks in your Oracle database that in the future may affect database throughput and response time.
To open the Impending Bottleneck Predication page
| For categories of timed statistics | For a category of Wait Event |
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Set bottleneck criteria
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Control |
Description |
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Perform an analysis of... |
Select Real Data (your database) or Sample Data (to experiment with). Note: Spotlight takes some time (typically about 10 days) to collect enough data to make valid predictions on the future performance of your Oracle instance. In the meantime use the prepared sample data to learn more about Predictive Diagnostics and how it works. |
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Within the processing period... |
Select an activity period to use for your prediction. The more selective this is the better the prediction. Tip: To define new processing periods or redefine an existing processing period see Peak Processing Periods. |
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For all collected data or For data collected since... |
Click all or the date to open Impending Bottlenecks Oracle Job. If you select a start date in Data Analysis Options then this text reads For data collected since.... Note: The start date should be a date for which recorded data exists. For example, you cannot select a date later than today's date. Use this setting to ignore data that occurred before a specific time. |
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Predict forward until... |
Select an end date for the prediction. |
Predictions for impending bottlenecks.
Impending Bottleneck Predictions displays projected statistics for potential bottlenecks on the database. These statistics are based on the details of the timed statistics collected by Predictive Diagnostics according to criteria set.
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Column |
Description | ||||||||
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Bottleneck Prediction Image |
The image displayed here corresponds to the most relevant bottleneck prediction for the timed statistic in this row.
The type of image reflects the shape of the prediction chart in either the Total Time or Average Time sub-page, and indicates the trend for the statistic, either as an average value or a percentage of total wait time, depending on the statistic. The chart style does NOT necessarily indicate that a problem exists.
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Timed Statistic |
A category of the timed statistics that can signal bottlenecks. Tip: To list the individual statistics, click the row. From Impending Bottlenecks select Details. | ||||||||
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Avg Time Now |
The average time taken NOW for events in this category, measured in milliseconds. | ||||||||
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Avg Time Predicted |
The predicted average time taken for events in this category at the end-date, measured in milliseconds. | ||||||||
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% Total Time Now |
The total time taken NOW for events in this category, measured as a percentage of the total time taken for all events. | ||||||||
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% Total Time Predicted |
The predicted total time taken for events in this category at the Predict forward until... date, measured as a percentage of the total time taken for all events. | ||||||||
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Severity Now |
A measure of the severity of the bottleneck now (0 = no bottleneck, 100 = severe bottleneck). | ||||||||
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Severity Predicted |
A measure of the severity of the bottleneck at the end date. | ||||||||
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Statistic ID |
Every timed statistic category is assigned an identifying value. | ||||||||
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Total Time Now |
The total time taken NOW for events in this category, measured in milliseconds. | ||||||||
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Total Time Predicted |
The predicted total time taken for events in this category at the end-date, measured in milliseconds. | ||||||||
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Wait Rate Now |
The number of waits per second NOW for events in this category. | ||||||||
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Wait Rate Predicted |
The predicted number of waits per second at the Predict forward until... date for events in this category. |
The color of the image represents the predicted severity of the timed statistic at the end-date.
Notes:
- Not all columns are visible by default. Use the Column Organizer to view hidden columns. Show, Hide & Order Columns
- When the Spotlight application window is too small to show the tabs for all the sub-pages at the same time, Spotlight will indicate the hidden tabs with scroll arrows. Click a scroll arrow to display the hidden tabs.
Prediction details for selected bottlenecks
| Detail | Description |
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| Every row in the Impending Bottlenecks Predictions table represents a category of timed statistics for which Spotlight has collected bottleneck data. |
To view the list of all statistics in the category, click its row in the table and open the Details page. The Details page shows performance data for events that contribute to the bottleneck, and predicts how the performance will change in the future. The Details page is only one of the pages displayed when you click a row in the Impending Bottleneck Predictions table. The Waits, Total Time and Average Time pages provide additional information on bottlenecks in the form of charts and explanatory text and, where possible, provide links to further information on those bottlenecks. |
| Show Waiting Events for the category of timed statistic |
Right click a row and select Waiting Events. Spotlight opens the Spotlight on Oracle Activity | Waiting Events page with statistics in the category of the selected row. |
| Show Waiting Events for the timed statistic |
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| Change Spotlight Options for Predictive Diagnostics |
Right click a row and select Predictive Diagnostics Options. This opens Predictions General Configuration. |