Configure cost and traffic control
- Latest Dynatrace
- How-to guide
- 3-min read
- Published May 07, 2026
After you activate Session Replay, all user sessions analyzed with RUM are also recorded with Session Replay. Around 100 kB of data is generated for every minute of a session and up to 1 MB or more is consumed by a fully recorded session. Because compression takes place on the client side, bandwidth consumption matches storage consumption—it's particularly advantageous for users on mobile devices with limited internet data or bandwidth. Session volume depends on a variety of factors, including the application size, session duration, and user interactivity with the application. You can limit the number of sessions recorded with Session Replay to reduce the volume of generated data. To do that, configure the cost and traffic control setting.
Adjust number of recorded sessions
To limit the number of sessions recorded with Session Replay
- Go to Web.
- Select the application that you want to configure.
- In the upper-right corner of the application overview page, select More (…) > Edit.
- From the application settings, select General settings > Enablement and cost control.
- Under Session Replay, enter the new value for Cost and traffic control.
Calculate number of recorded sessions
To determine the actual percentage of user sessions recorded with Session Replay, you should consider the cost and traffic control for RUM setting defined for your application, which is the overall percentage of user sessions to be analyzed with RUM.
Formula
Use the following formula to calculate the actual percentage of sessions recorded with Session Replay:
Actual percentage of sessions recorded with Session Replay = cost and traffic control for RUM × cost and traffic control for Session Replay.
Calculation example
| Parameter | Value |
|---|---|
Cost and traffic control for RUM | 50% |
Cost and traffic control for Session Replay | 20% |
Actual percentage of sessions recorded with Session Replay | 50% × 20% = 10% |
Total number of sessions | 2500 |
Number of sessions analyzed with RUM | 2500 × 50% = 1250 |
Number of sessions recorded with Session Replay | 2500 × 10% = 250 |
Sessions that span multiple applications
When you have several applications and a user switches from one application to another, Dynatrace creates only one user session, with all the user activity recorded in the context of that session. Such a session is attributed to all the applications that the user visited.
To determine whether a multi-application session should be recorded with Session Replay, Dynatrace uses the cost and traffic control configuration of the application that the user entered first.
For example, suppose that the cost and traffic for Session Replay is set to 1% for application A and 100% for application B. When the user first enters application A and then switches to application B, Dynatrace uses the 1% value to determine whether to record the session with Session Replay. This might result in a smaller or greater percentage of sessions recorded with Session Replay compared to the configured values of the cost and traffic control setting.
If a session spans an application for which Session Replay is deactivated, Session Replay data is missing for the part of the session recorded in that application.