User actions

A user action is an interaction with the web browser that involves a call to a web server, which can potentially have multiple nested calls.

User action types

A user action can be a page load, an XHR action or a custom action. The key difference among these action types is the way action duration is calculated and that for each type there are different metrics available.

Page load

A page load is an actual page loading in your browser. If you enter a URL in your browser and press enter, a page load occurs. During a page load, many resources are loaded, including images, HTML, and CSS.

The action duration in this case is the time required for the complete page load. More specifically, the start time of the user action begins with the W3C navigationStart time, if available. If not available, the start time begins when the Real User Monitoring JavaScript code is initialized in the browser. The end time is when the last onload handler has completed its task. The onload handler is an event handler in JavaScript that's used to call the execution of JavaScript after a page, frame, or image has completely loaded. If any XMLHttpRequests (see XHR actions below) are started by an onload handler, the user action ends when the XMLHttpRequest is complete.

speed index - navigation timings

Resource timing steps

The following measures are used to chart the duration of specific steps in the page loading process.

Measure Description Definition in terms of W3C specification
DNS Time spent or resolving domain names. window.performance.domainLookupEnd - window.performance.domainLookupStart
Connect Time spent establishing a socket connection from the browser to the web server. window.performance.connectEnd - window.performance.connectStart
SSL Time spent establishing a secure socket connection from the browser to the web server. window.performance.connectEnd - window.performance. secureConnectionStart
URL Redirection Time spent following HTTP redirects. window.performance.redirectEnd - window.performance.redirectStart
Request Time spent waiting for the first byte of the document response. window.performance.responseStart - window.performance.requestStart
Response Time spent downloading the document response. window.performance.responseEnd - window.performance.responseStart
Total Time between the response being delivered and the OnLoad event. window.performance.loadEventEnd - window.performance.domLoading

XHR action

Most modern applications, including single page applications, rely on a single page load that downloads the framework and initializes the page. After that, the DOM of the page is changed via JavaScript and all communication with the web server is done via XmlHttpRequest or via fetch().

Dynatrace continuously tracks user interactions with each page. If user interaction leads to XmlHttpRequests or fetch() calls, an XHR action is created. Dynatrace also detects if there are additional XHRs triggered in the callback of the initial XHR and so on. In this case, Dynatrace waits until all requests are finished. By monitoring the DOM, Dynatrace can also identify resources that were added in the callbacks. Dynatrace then waits until those resources have finished downloading before ending the action.

An XHR action starts with the user's click on a control on a web page. All metrics are calculated in relation to this point in time and are based on the initial XHR that triggers the user action.

Fetch API

The Fetch API provides an interface for fetching resources (including across the network). It is similar to XMLHttpRequest, but the API provides a more flexible feature set. The generic definitions of Request, Response and other network request objects in Fetch allow them to be used at any time they are needed, whether it’s for service workers, Cache API, or anything that handles or modifies requests and responses. Fetch also supports the Cross Origin Resource Sharing (CORS).

User actions based on the Fetch API appear in Dynatrace as XHR actions. You can configure Dynatrace to automatically detect and capture Fetch API request information.

Custom user actions

Rather than relying on default user action generation, you may want to fine-tune your Real User Monitoring by adding additional user actions directly into your application’s HTML. This can be useful if our automated user-action generation doesn’t catch specific actions or you want to introduce specific fine-grained timings into your application monitoring. For example, you could measure how long it takes to open a JavaScript-only drop-down menu, or measure the duration time of some JavaScript code. To define custom actions you can use the JavaScript API for Real User Monitoring.

User action naming rules

Many applications allow users to accomplish the same goal through different UI controls. When monitoring such applications, it can be difficult to differentiate between actions that have the same result and goal, but are executed using different parts of the application UI. Likewise, if the UI of an application is translated into multiple languages, the same application function or control may appear under varying names. With user action naming rules, Dynatrace can detect such subtle variations and intelligently group related user actions (i.e., user actions that achieve the same goal) into logical groups for monitoring.

Dynatrace automatically removes certain common sessionid tokens from user action names (for example, jsessionid for Java containers, the default sessionid for PHP, and CFID and CFTOKEN for ColdFusion). Nonetheless, there are numerous session ID variations that may be present in your environment. If Dynatrace doesn't automatically recognize and remove session IDs from certain user action names you encounter, you'll need to configure custom naming rules for those user actions.