RUM Data | Page Load Time Breakdown

This document will help explain datapoints and graphs in the Page Load Time tab of a RUM report. This is a companion document for RUM, and is best used once you have generated a RUM snippet and are actively collecting data. 

For setup instructions, click here. 

Page Load Time Trend

The Page Load Time Trend measures page load compared against the number of page views for a URL or segment, and a baseline of the previous week's worth of data. 

First Byte 

First byte is the elapsed time between the browser making and receiving the first byte of the HTML response. 

First Paint 

First paint is the time elapsed before the browser first renders significant content on screen, and is similar in nature to Time to Interactive (TTI). The difference lies in interactivity. With first paint, the user is seeing meaningful content on screen. With TTI, the user can also interact with a page. 

It is common for First Paint and TTI metrics to be close or even similar, but TTI will always be greater than First Paint. 

Time To Interactive (TTI) and TTI Baseline

Time To Interactive (TTI) is the time elapsed before a page becomes fully interactive. TTI is the primary or key metric in RUM monitoring, and represents the elapsed time before a user is able to both see and fully interact with a website. 

A TTI baseline is used, representing the above metric averaged over the previous week’s worth of data.

Page Load Time Distribution

The Page Load Time distribution is a histogram depicting the distribution of users who are experiencing each level of the Apdex threshold defined for your check. The Y axis depicts the number of page views, while the X axis depicts page load time distribution up to the maximum recorded value. 

Apdex Graph

A graph visualizing which users fit into which Apdex category. Represented via either donut or bar graph. Hover over specific segments of data to see more details on each segment, or click a segment to add/remove it from the graph. 

Apdex and Aggregation

Apdex, being a general measure of user satisfaction, is best examined within a larger pool of data. We suggest adjusting date range to include more page view data.

Page Load Time Breakdown

The page load time breakdown is a bar graph that helps visualize the sequential components of page load, from initial connection through TTI and the loading of all assets. The date range selected is compared to a baseline.

Hover over a specific portion of each graph to review a detailed breakdown of metrics.

Each of these datapoints is described in detail below:

• Connection: This represents the time it takes to perform a DNS lookup, establish the connection and send the web page request.
• Server: This represents the time it takes the server to process the request and initiate a response.
• Transfer: This value represents the time it takes for the browser to download the web page's HTML.
• Client: This value represents the elapsed time for browser rendering and javascript processing. 
• Assets: This represents the time it takes for the browser to fully load the page with images, videos, and the execution of any Javascript.

See our Logic and Definitions document for more details.

Want to see our checks in action? Check out our YouTube Library for more!