Digital Experience Monitoring (DEM units)
In addition to the application and infrastructure monitoring provided by OneAgent, you may also require Dynatrace Synthetic Monitoring, Real User Monitoring, and Session Replay. These capabilities are consumed based on Digital Experience Monitoring units, otherwise known as DEM units.
The amount of DEM units you need depends on how many Synthetic monitors you want to run and how many user sessions you need to monitor. The table below explains the rate at which DEM units are consumed per each capability type and unit of measure.
|Unit of measure||Capability||Consumption per unit of measure|
Browser monitors, browser clickpaths
Real User Monitoring (Without Session Replay playback)
Real User Monitoring session captured with Session Replay
Real User Monitoring
Real User Monitoring
Third-party synthetic result
Third-party synthetic API ingestion
User sessions are charged per application, even if a session spans multiple applications from the same domain. Only user sessions from real users are counted in your consumption of user sessions. User sessions from synthetic users and "robots" aren't counted when calculating your monitoring consumption.
Once a user session has about 200 user actions, a new session is created and all subsequent user actions are included in the new user session. There is no extra charge for additional user sessions that Dynatrace creates following such session splits.
Data types for properties are weighed differently and affect billing, monitoring, as well as consumption. Short strings (fewer than 100 characters) and numeric (long strings, double, or dates) data types are counted as 1 property each. Long string data types are counted as 1 property per 100 characters.
Real User Monitoring
A single Real User Monitoring session (otherwise known as a "user session") is defined as a sequence of interactions between a user with a browser-based web application or a native iOS or Android mobile app within an interval and with at least two user actions. A user action is a mouse-button click, finger tap, or app start that triggers a web request (for example, a page load or a page-view navigation). Interactions that include only one user action are considered “bounced” and aren't counted. A user who interacts with more than one web application or app at the same time consumes one session for each of those web applications or apps, except when the interaction is considered “bounced”. Interactions with hybrid mobile apps, that for technical reasons include a web application and a mobile app will only be considered as a single session.
A billed session ends when the user session ends, or after 60 minutes of continuous interaction with the web application or mobile app.
If you've set up an annual RUM sessions quota, your usage will reset annually.
Real User Monitoring DEM consumption example
Say, for example, that a user has been interacting with a web application or mobile app for a period 4 continuous hours. From a license perspective, a session ends after 60 minutes of continuous interaction, after which a new session is resumed for the next 60 minutes. Therefore, a 4-hour session is the equivalent of 4 licensed sessions. Without Session Replay data, this session costs
4 * 0.25 = 1 DEM Unit. With Session Replay data, the session costs
4 * 1 = 4 DEM units.
Synthetic actions and requests
A browser monitor or browser clickpath “synthetic action” is an interaction with a synthetic browser that triggers a web request that includes a page load, navigation event, or action that triggers an XHR or Fetch request. Browser monitors perform a single synthetic interaction (for example, measuring the performance and availability of a single URL) and consume one synthetic action per execution. Clickpath monitors are sequences of pre-recorded synthetic actions. Clickpaths consume one action per each interaction that triggers a web request. Scroll downs, keystrokes, or clicks that don't trigger web requests aren't counted as actions.
An HTTP monitor consists of one or multiple HTTP(S) requests (for example, GET, POST, HEAD requests). Each request executed by an HTTP monitor equates to one synthetic request.
# Synthetic actions/requests consumed per monitor = (# Synthetic actions included in monitor) x (# Executions per hour) x (# Locations) x # Hours
XHR or Fetch requests that are made by a synthetic browser as the result of a user action like a page load, which isn't directly triggered by user input, don't result in user actions and therefore aren't counted. Such XHR and Fetch calls are considered child requests of synthetic actions.
Synthetic actions/requests calculation example
For example, a recorded browser clickpath that navigates through 2 pages and clicks 1 button that triggers an XHR or Fetch request consumes 3 synthetic actions. If such a synthetic monitor runs every 15 minutes from 2 locations for 1 day, the browser clickpath will consume 576 synthetic actions per day.
3 (synthetic actions) x 4 (monitor executions per hour) x 2 (locations) x 24 (hours per day) = 576 (synthetic actions)
For more details, see Synthetic Monitoring.
Digital Experience Monitoring overages optional
If you've arranged for Digital Experience Monitoring overages (meaning, your account allows you to exceed the maximum limit of DEM units), the units you consume as overage are counted just as with regular DEM Unit consumption; each additional overage session or synthetic test increases the amount of DEM units consumed by your account. To add or remove overages from your account, contact Dynatrace Sales.
Free tier of action and session properties
You can gain more information from a session or user action by configuring additional defined properties. We currently offer a free tier of 20 defined properties per application. As shown in the table, the DEM unit cost per session increases by 0.01 DEM units for each additional defined property.
For example, 100 sessions with 25 defined properties consume
100 * (25 - 20) * 0.01 = 5 DEM units for additional defined properties. The total DEM unit cost in this case is 30 DEM units (
5 DEM units (additional defined properties) + 25 DEM units (100 sessions; 1 session = 0.25 DEM units) = 30 DEM units.