IBM Performance Management

Adjusting and comparing metrics over time

Some of the dashboard widgets show metrics that are based on a time range, and other widgets show only the most recent metrics. When a time selector is displayed in a dashboard's Status Overview tab, you can adjust the time range for the widgets whose values are derived from historical data samples. Adjust the time to show up to 1 day of historical data. For attributes that have up to one week of data collected and presented in a line chart, you can compare today's values with another day.

Procedure

  1. If the Application Performance Dashboard is not displayed, select it from the Performance menu.
  2. Navigate to a dashboard for which you want to adjust the time range or compare time spans and click the time selector. The initial setting is Last 4 Hours.
  3. Select one or more of the following options:
    • To change the time range displayed, select Last 4 hours, Last 12 hours, or Last 1 day.
    • To compare the time range displayed in a line chart with the metrics from a different day, select Compare to and select Yesterday or another day up to 1 week ago.
    • To have the time range applied to the dashboards of all defined applications in your monitored environment, select All Applications. Otherwise, leave the setting at Only This Application to apply the time range to only the current application (such as My Components). The Compare to selection is effective only for the current page.

Results

  • If you are viewing historical data without comparison, all dashboards in the current application (or all applications) are affected by the change.
  • If you are viewing a comparison, only line charts in the current page are affected. A line is drawn for each KPI to show the metrics from the chosen day. Some line charts are unavailable for comparison, as indicated by a watermark on the chart: No Comparison Available. This can happen with newer managed resources that have not yet collected at least 1 day of data.
  • Any widgets for which no historical data is collected continue to display the most recent values.
  • Data points are distributed along the full length of the chart for the selected time range. Time stamps are displayed on the axis label, starting with the earliest time stamp and ending with the most recent time stamp. Check the oldest data sample to confirm whether a partial range or the full range of historical data is displayed.
  • Data sent to the charts and tables is normalized to GMT (Greenwich Mean Time). The Timestamp axis prints time stamps based on the time zone of your browser. If your time zone uses Standard Time and Daylight Saving Time, the time stamp displayed during the transition hour is displaced by one hour. Consider, for example, that you are viewing a line chart in Spain and the time changes from 2:00 AM Standard Time to 3:00 AM Daylight Saving Time. The discrepancy between the GMT of the data and the local time of the time stamp results in the time stamps having a gap of one hour from 2:00 AM to 3:00 AM. If you are viewing the same chart in New Zealand during the switch from 3:00 AM Daylight Saving Time to 2:00 AM Standard Time, the time stamps from 2:00 AM to 3:00 AM are repeated.