Histogram visualization

Latest Dynatrace

When to use histogram visualization

Use a histogram to visualize the distribution of numerical values.

Examples

Example 1

Histogram example

The histogram visualization above is based on the following query.

fetch spans
| filter span.kind == "server"
| filter duration < 1s
| summarize count(), by:{range(duration, 10ms)}

Example 2

Histogram example

The histogram visualization above is based on the following query of bizevents.

fetch bizevents
| filter event.type == "com.easytrade.trade-closed"
| filter direction == "longsell"
| filter amount <= 10000
| summarize count = count(), by:{range(amount, 300)}

Example 3

Histogram example

The histogram visualization above is based on the following query. This shows the distribution of risk scores for open security events.

fetch events
| filter event.kind == "SECURITY_EVENT"
| filter event.status == "OPEN"
| summarize count = count(), by:{range(vulnerability.risk.score, 0.5)}

Example 4

Histogram example

The histogram visualization above is based on the following query. This is a variation on the previous example that shows an additional split by the security event status.

fetch events
| filter event.kind == "SECURITY_EVENT"
| summarize count = count(), by:{range(vulnerability.risk.score, 0.5), event.status}

Title

Use this field to add a title. The edit box is displayed at the top of the options panel.

Title edit box

  • You can use emojis such as 😃 and 🌍 and ❤️.
  • You can use variables.

Example:

  1. Define variables called Status and Emoji in your dashboard.
  2. Set Title to Current $Emoji status is $Status.
  3. Set Status to Good.
  4. Set Emoji to 🌍.

The title will be displayed as Current 🌍 status is Good.

Visualization

If you aren't sure that you chose the right visualization, use the visualization selector to try different visualizations.

Data mapping

The data mapping section shows how a column of your result is mapped to the visualization.

For example, when working with DQL and a timeseries, in the result we have a column with a value array for each series (one row with that one cell of values). For a timeseries, this mapping is done fully automatically, but the data mapping shows you which underlying column is mapped.

The histogram is defined by an array of bins where each bin represents a continuous range of values. It has two key parameters:

  • Value: the count or frequency (value) that determines the height of individual bars
  • Range: determines the width (size) of individual bars

Histogram chart options

To learn about options quickly and decide what works best for you, turn options on and off and see the effect immediately on your chart. For example, does it look best with a label or without? Turn that option on and off and see for yourself.

Color palettes

You can select a color palette from the list under Color palettes.

Legend position

Select where to display the visualization legend:

  • Automatic—Dynatrace chooses an appropriate location
  • Hidden—no legend is displayed
  • Bottom—the legend is displayed along the bottom of the visualization
  • Right—the legend is displayed on the right side of the visualization

X-axis

Sets the scale of the X-axis:

  • Logarithmic
  • Linear

Min

The minimum value of the visualization's x-axis.

  • Auto—Dynatrace automatically selects a suitable minimum based on data (0 or min-value).
  • Min-value—The minimum is set to the minimum data value.
  • Custom—Displays an input field for you to enter a custom minimum value.

Max

The maximum value of the visualization's x-axis.

  • Auto—Dynatrace automatically selects a suitable maximum based on data (0 or max-value).
  • Max-value—The maximum is set to the maximum data value.
  • Custom—Displays an input field for you to enter a custom maximum value.

Label

Text to display as a label for the Y-axis.

Y-axis

Sets the scale of the Y-axis:

  • Logarithmic
  • Linear

Min

The minimum of the visualization range.

  • Auto—Dynatrace automatically selects a suitable minimum based on data (0 or min-value).
  • Min-value—The minimum is set to the minimum data value.
  • Custom—Displays an edit box for you to enter a custom minimum value.

Max

The maximum of the visualization range.

  • Auto—Dynatrace automatically selects a suitable maximum based on data (0 or max-value).
  • Max-value—The maximum is set to the maximum data value.
  • Custom—Displays an edit box for you to enter a custom maximum value.

Label

Text to display as a label for the Y-axis.

Query limits

Use the Query limits section to check and adjust the Grail query limits per notebook section or dashboard tile. These settings determine the maximum limits when fetching data. Exceeding any limit will generate a warning.

Dashboard sections and notebook tiles created in Dynatrace earlier than version 1.296 are not affected. Those existing tiles/sections will return the same results as before.

Read data limit (GB)

The limit in gigabytes for the amount of data that will be scanned during a read.

Record limit

The maximum number of result records that this query will return. Default: 1,000 records. To see more records, you need to increase the value of Record limit.

  • If your query has no limit, such as

    fetch logs

    the value of Record limit is applied. By default, you will see up to 1,000 records.

  • If your query also includes a limit, such as

    fetch logs
    | limit 2000

    the lower of the two values (either limit in your query, or Record limit in the web UI) is applied.

    In the example above, you would still see only 1,000 records unless you increased the value of Record limit.

Result size limit

The maximum number of result bytes that this query will return. For better performance with typical queries and smaller documents, the default is set to 1 MB.

Sampling (Logs and Spans only)

Results in the selection of a subset of Log or Span records.

Thresholds

Configure thresholds

To configure thresholds in a dashboard or notebook visualization

  1. Select to edit the visualization tile.

  2. Select Thresholds.

    • In Dashboards, select the Visualize tab in the side panel, and then select Thresholds.
    • In Notebooks, select Thresholds in the side panel.

  3. Select Add threshold.

  4. Define the thresholds. For each range:

    • Select a color to display for that range
    • Select the operator to define the threshold for that range
    • Enter a static value to compare (using the selected operator) with the returned value
    • Enter a label to associate with the defined range.
      • Labels apply only to charts with a Y axis, such as timeseries charts and the categorical bar chart.
      • Labels can't be defined for tables and the single value chart.

This example uses a bar chart, but the options apply to other visualizations.

  1. In Dashboards, create a dashboard.

  2. Select and, in the Snippets section of the menu, select Metrics > Chart top 10 hosts by CPU usage.

  3. In the section edit panel, select the Visualize tab and select Bar chart. (To simplify the examples, we hid the chart legend (see Legend in Bar chart options), but that makes no difference to thresholds.)

    Chart before adding thresholds

  4. Select Thresholds.

    Select "Thresholds"

  5. Select Add threshold.

    Select "Add threshold"

    An empty set of threshold fields is displayed.

    Empty thresholds settings

  6. Define the thresholds for the displayed metric. You can observe your changes in the Y axis of the chart.

    In this example, we define three ranges of CPU usage with corresponding colors and labels.

    Three ranges defined

    You can see the ranges displayed on the Y-axis and in the tooltip.

    Chart after adding thresholds: thresholds on Y-axis and in tooltip

To reset to defaults (discard threshold settings), select the trash can next to the item.

Edit thresholds

  1. Select to edit the visualization tile.

  2. Select Thresholds.

    • In Dashboards, select the Visualize tab in the side panel, and then select Thresholds.
    • In Notebooks, select Thresholds in the side panel.

  3. From this point, you can do the following (expand rows for details):

    To add thresholds (if the selected visualization supports additional thresholds), select Add threshold.

    Thresholds: add thresholds

    To turn off (hide) existing thresholds, use the switch. No settings are lost. You can turn them back on if you change your mind.

    Turn off thresholds

    To delete existing thresholds, select the trash can .

    Delete thresholds

    To change existing threshold settings, just edit the fields.

    Edit thresholds

    To add a range to existing thresholds, select Add range.

    Add thresholds range

    To delete a range from existing thresholds, select the delete button in that row.

    Delete thresholds range

Units and formats

To override the default units and formats in a dashboard or notebook visualization

  1. Select to edit the visualization tile.

  2. Select the Visualize tab.

  3. Select Units and formats.

  4. Select Override.

  5. Select Override

  6. In the dropdown list, select the item for which you want to add a unit override.

    This is a numeric column of the underlying DQL result, so it varies according to the query. For example:

    • A fetch events query returns events. The dropdown list here lets you select a numeric field (such as transfer_size) from the results.
    • A timeseries avg(dt.host.cpu.usage) query returns a single timeseries for avg(dt.host.cpu.usage). That timeseries is then the only selectable option in the list.

  7. Define the override.

    • Default unit: The base unit in which the values were captured. It's None if it was not included in the DQL result, or its automatically defined by the unit passed from the DQL result. This field doesn't lead to any conversion.
    • Displayed unit: Once you define a default unit, you can use Displayed unit for conversion. For example, if the DQL result defined your numeric value in the result as Bytes, Displayed unit now offers a suitable list of byte conversions such as Kilobyte and Megabyte. Unlike the Default unit, the Displayed unit is always a numeric conversion.
    • Decimals displays the default number of decimals (degree of precision) to display. To see it in action, change the Decimals selection and observe the change in the visualization.
    • Suffix displays the suffix to display after the unit. To see it in action, enter a string and observe the change in the visualization. When you don't find the unit you're looking for, you can use Suffix to display the desired unit.

  8. Turn on Abbreviate large numbers if you want to display large figures in abbreviated form. For example, 1053 becomes 1.1K.

To reset to defaults (discard override settings for the selected item), select the trash can next to the item.

This example uses a line chart, but the options apply to other visualizations.

  1. In Dashboards, create a dashboard.

  2. Select and, in the Snippets section of the menu, select Metrics > Chart average CPU across all hosts.

  3. In the section edit panel, select the Visualize tab and select Line chart.

  4. Select Units and formats.

    Select Units and formats

  5. Select Override.

    Select Add Override.

  6. In the dropdown list, select the metric for which you want to add an override. There's only one metric to select in this example.

  7. Define the override for the displayed metric. You can observe your changes in the Y-axis of the chart.

    • Default unit displays Percent (%), which is the default unit for the selected metric. Try a different setting, such as One to instead display the result as a fraction of 1.

    • Displayed unit displays Auto. You can change it to a different unit, such as One to instead display the result as a fraction of 1.

      Only linear and static conversions are supported. For example, you cannot convert Degree Celsius(°C) into Degree Fahrenheit(°F), or convert Usd(US$) into Eur(€).

    • Decimals displays the default number of decimal points (degree of precision) to display. To see it in action, change the Decimals selection and observe the change in the visualization.

      For example, change this:

      Decimals setting before

      To this:

      Decimals setting after

    • Suffix displays the optional suffix to display after the unit. To see it in action, enter a string and observe the change in the visualization.

To reset to defaults (discard override settings for the selected metric), select the trash can next to the metric.