Panels and Visualization
This domain assesses whether you can choose an appropriate visualization and configure panel and field options so the result is readable and truthful. Questions often hinge on standard options, overrides, thresholds, units and legend behavior.
Choosing the visualization
Use Time series for values over time, Stat for one or a few current values, Gauge for progress against a range, Bar gauge for comparing magnitudes, Table for multiple fields and precise reading, Pie chart for simple proportions, Heatmap for distribution over time, Histogram for value distribution, and Logs, Traces, Geomap, Canvas or Text for specialized content. The visualization should answer the question, not merely display the data.
Panel editor and field options
The panel editor groups work into Query, Transform, Alert and Panel options. Standard options include unit, min/max, decimals, display name, color scheme, thresholds, value mappings and overrides. Overrides can target fields by name, regex, type or query, and they take precedence over the base field options. Legend modes include table, list and hidden; legend calculations can show last, max, mean and other values. Tooltip modes control whether one series or all series are shown. Data links and panel links turn values into navigation.
Worked example
You need a CPU gauge that is green below 70%, yellow from 70% to 85%, and red above 85%. Set the unit to Percent (0-100), set min to 0 and max to 100, then add two thresholds: 70 and 85. Choose Absolute threshold mode so the numbers are percentages of the unit range. If you choose Percentage mode, thresholds are calculated relative to min/max; with 0-100 the result looks the same, but with min 20 and max 80 it would not. Keep the gauge's min/max explicit so the needle cannot imply a misleading range.
Traps that cost marks
- Leaving a gauge on automatic min/max and misrepresenting progress.
- Confusing absolute and percentage threshold modes.
- Expecting base field options to beat overrides; overrides win.
- Using a pie chart for many categories or for values that need precise comparison.
- Omitting units or decimals, making the panel ambiguous.