Customizing End Point Thresholds

The health of an end point is based on how many traces took longer to execute than the response time threshold.

By default, Spring Insight uses a response time threshold of 200ms. In the response time histogram, the upper limit of the y-axis is 4-times the threshold, or 800 ms by default. The time chunks of the y-axis are not evenly distributed, but rather, broken up in a way to show the distribution of the response times of the recent End Point traces.

If, for a given trace or subset of traces, you find that the default threshold is too high or too low, you can change it. For example, if you find that all your response times for the .*show.* methods are almost always below 100 ms, you might want to set this as the threshold. The histogram will then have a smaller range, and thus show more fine grained information. Similarly, if you have an end point in which the response times are always over 200 ms, the health of this end point will almost always show as frustrated. If you decide that it is acceptable if a threshold of 300ms is acceptable, then you can change it for this End Point so it will show as appropriately healthy.

In other words, if you change the response time threshold for an End Point, you change the criteria that Spring Insight uses to decide whether it is healthy or not.

The following graphic shows the health and response time histogram for an End Point whose threshold is the default (200ms):

Note the upper limit in the histogram of 800ms, and the satisfied range is under 200ms. A response time of over 200ms but under 800ms is tolerated, but over 800ms is frustrated, or unhealthy.

Note that all response times are under the default threshold so the End Point is healthy. If the response times are all significantly below the default threshold, it might be a good candidate to lower the threshold to get more fine-grained response time information.

To change the threshold for an End Point or set of End Points:

  1. From the main Spring Insight dashboard, click the Administration tab.

  2. Click End Point Threshold in the left pane.

  3. In the right pane, click New:

  4. In the Rule field, enter a regular expression that corresponds to the End Point or End Points for which you want to change the threshold. For example, if you want to specify all show methods, enter .*show.*:

  5. Enter the new threshold. As described above, the default Spring Insight threshold is 200 milliseconds.

  6. Click Save. The Matching End Points column automatically shows the number of End Points that match this rule; the number is a link. Click on this link to see the list of matching End Points.

  7. Click the Make Permanent to apply the change. The new rule appears in the table:

  8. If you have more than three rules, you can use the up and down arrow buttons to change the order in which Spring Insight applies the rules. Insight applies the rules from first in the list to last. The default rule (.*) should always be last.

  9. Browse to a trace that matches the rule. Note that the y-axis of the Response Time Histogram now has an upper limit of 4-times the new threshold. The health of the End Point is now satisfied when its response time is below the new threshold. In our example, the new threshold is 100 ms and so the upper limit is 400 ms: