Use the Metric Baselines page to:
Review or change the active baseline.
Manage adaptive thresholds for the active baseline.
Configure the moving window baseline.
Access the Manage Adaptive Thresholds page.
Access the Baseline Normalized Metrics page.
Access the Manage Static Metric Baselines page.
Access the Edit Settings page to change the AWR retention or collection period.
Enable or disable baselining for all defined baselines.
Only one baseline can be active at a time. The active baseline controls the automatic setting of metric thresholds.
Consider the following guidelines as you review the Metric Baselines page.
For either a moving or static baseline time period, Enterprise Manager computes statistics on all the metrics referenced by the baseline.
If you select the Moving Window option, the time period you define for this baseline, such as trailing 7 days, moves with the current time. The most recent 7-day period becomes the baseline period (or reference time) for all metric observations and comparisons today. Tomorrow this reference period drops the oldest day and picks up today.
The single integer for a moving period is the "rolling" interval width (the ending time is today, and the beginning time is today- n days) that calculates metric statistics for later comparisons. Enterprise Manager computes moving window statistics every day, rather than sampling.
The retention period default for the Moving Window option is Trailing 7 days. You can optionally add Trailing 21 days, Trailing 35 days, or Trailing 91 days by clicking the Change AWR Retention link at the top of the page. No other number other than these four is supported. If you increase the AWR retention, additional options become available in the Time Grouping drop-down list. For instance, if the default Trailing 7 Days is currently your only choice for a moving window baseline, the Time Grouping list provides you with five choices. If you then change the AWR retention to 35 days, two additional options become available: By Hour of Day, and By Day and Night per Day of Week.
If you select the Static Baseline option, the two dates for a static baseline period define the fixed interval that calculates metric statistics for later comparisons. Consequently, Enterprise Manager only computes static baseline statistics once, which is when the baseline is created.
Time grouping options available for a baseline depend on the size of the time period for the baseline, as shown in the following table:
|
Option |
Baseline Period |
|---|---|
| By Day and Night |
Creates 2 groups:
|
| By Weekdays and Weekend |
Creates 2 groups:
|
| By Day and Night, over Weekdays and Weekend |
Creates 4 groups:
|
| By Day of Week | Creates 7 daily groups. |
| By Day and Night, per Day of Week |
Creates 14 groups:
|
|
By Hour of Day |
Creates 24 hourly groups. |
| By Hour of Day, over Weekdays and Weekend |
Creates 48 groups:
|
| By Hour of Day, per Day of Week |
Creates 168 groups:
|
To view baseline normalized metrics, click the Baseline Normalized Metrics link in the Related Links section.
To manage and create static metric baselines, click the Manage Static Metric Baselines link in the Related Links section.
There are two situations in which you may want to disable baselining:
Baselining imposes additional data management (computation and storage) and baseline actions (jobs with potentially the same needs) on the server. Some environments may not be able to afford this cost.
If the performance characteristics are non-repeating and vary considerably, comparing against past times becomes increasingly less relevant for current measurements. This type of system is not well-suited for baselining.
To view how this baseline influences alerts, go to the Manage Adaptive Thresholds page. For each metric that has a setting in that page, Enterprise Manager automatically sets thresholds using the statistics calculated over the corresponding time group.
Related Topics
Enterprise Manager Information Roadmap
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