UX Time and Network Time metrics

As of the April 2017 release, Dynatrace Synthetic collects two new metrics that are reported in the Waterfall summary page and the Waterfall page:

  • UX Time – The user experience time: the total time for the step, from the DNS lookup for the first object downloaded to the last byte downloaded for the last object, including any client processing time.
  • Network Time – The total time for the step, from the DNS lookup for the first object downloaded to the last byte downloaded for the last object, excluding any client processing time.

The following figure illustrates how the waterfall charts UX Time and Network Time from the start of a page load (PS) through the end (PE).

At this time, UX Time and Network Time are only reported in the Waterfall summary page and Waterfall page. In earlier Dynatrace Portal releases, the Dynatrace Synthetic platform has reported a single Response Time metric. This metric is still used in Portal pages such as interactive charts, the Trend details page, and custom dashboard charts, and in alerts.

To understand how UX Time and Network Time relate to Response Time, it is important to understand how the test setting Include client (non-network) time in results works with test execution and how the setting affects collection of these metrics.

The Include client (non-network) time in results setting affects the Response Time value:

  • When the setting is disabled, Response Time is the total time for the step from the first object DNS lookup to the last byte downloaded for the last object, excluding any client processing time. This is the equivalent of the new Network Time metric.
  • When the setting is enabled, Response Time is the total time for the step from the first object DNS lookup to the last byte of the last object, including any client processing time. This is the equivalent of the new UX Time metric.

When Include client (non-network) time in results is disabled, UX Time is equal to 0 (zero).

When Include client (non-network) time in results is enabled, W3C metrics are collected during test execution. However, these metrics aren't used to calculate UX Time or Network Time.

We recommend that you run all tests with Include client (non-network) time in results enabled, so you can monitor both Network Time and UX Time, and so you can use W3C metrics to evaluate performance.