Flashduty RUM Performance Issue Diagnosis Guide

Overview

Optimizing pages helps identify the root causes of browser performance issues based on real user traffic data. Browser metrics, such as Core Web Vitals (CWV) and FlashDuty custom loading time metrics, are used to troubleshoot slow page loading. These metrics assess the complete page loading time from the user's perspective.

For deeper analysis, the optimization page provides detailed breakdowns of Core Web Vitals by user demographics (such as browser, region, and application version). You can leverage this information to track performance trends, understand which user groups are most affected, and optimize precisely.

Diagnosis and Optimization

You can navigate to the Optimization page, located under the Performance Monitoring menu, and select the metric you want to analyze. You can also access this feature by viewing the corresponding performance data in the analysis dashboard.

Metric Selection

After selecting a page and metric, you can begin to gain insights into performance data:

Click on a metric card to select the metric to analyze (currently supports LCP, FCP, INP)

Select a group in "Show Filter Breakdown"

Evaluate metrics at different percentiles, for example, p75 evaluation represents the 75th percentile value.

Data Viewing

You can view how the metric performs under different conditions by adjusting the data grouping method or modifying filter conditions, thereby advancing the diagnosis and optimization work.

Problem Diagnosis

First, troubleshoot resources and errors. In the problem diagnosis section, you can see resources and errors that users encounter on the page that may affect metric performance. For example, for Largest Contentful Paint (LCP), you can view resources loaded before LCP is triggered. Since LCP is a metric of the time required for the largest element to load on the page, you can diagnose issues from both resource loading and error resolution perspectives.

Optimize Resource Loading and Time Consumption

You can view resource loading in this view, focusing on optimizing resources that take longer to load.

You can also check which resources cause rendering issues under the "Blocking Resources" panel.

Resolve Errors

Focus on recurring errors that may cause problems, as these exceptions also affect page performance.

View Event Samples

If you cannot locate key information more accurately during the resource analysis phase, you can select appropriate event samples in the event sample block for more detailed context analysis.

The waterfall chart shows the timeline of events when the metric was captured. To view the context of the rest of the page activity, scroll down to the event line related to the event.
You can use the dropdown menu in the top left to select another sample event, and expand any event in the waterfall by clicking on it to view the side panel.
You can also select an appropriate set of events for problem analysis and diagnosis by filtering event types and various filter options.

Performance Optimize

Flashduty RUM Performance Issue Diagnosis Guide#

Overview#

Diagnosis and Optimization#

Metric Selection#

Data Viewing#

Problem Diagnosis#