trace_analysis_without_better_context_framing.md

Trace events analysis

{
\"width\": 600,
\"height\": 400,
\"timeline\": {
\t\"min\": 3375003509,
\t\"max\": 3375288.8310000002,
\t\"range\": 3375288.8310000002
},
\"searchEvent\": {
\t\"pid\": 34224,
\t\"tid\": 31544,
\t\"min\": 3375003509,
\t\"max\": 3375288831,
\t\"range\": 3375288831
}
}

The selected callframe is a Function call originating from a Next.js framework chunk. This function call is executed as a microtask, triggered by a user click event. It represents a significant portion of the work performed in response to the click.

Execution Context:

• Ancestors: This Function call is part of a chain initiated by a user Task which led to an Event: click. The click event handler (v8.callFunction) then queued microtasks (Run microtasks), one of which is this selected Function call.
• Descendants: The selected Function call spawns two main branches. One branch involves a series of anonymous functions and calls related to styling (css, renderRule, _renderStyleToClassNames) and DOM property retrieval (getPropertyValue) which triggers Recalculate style. The other branch (oK -> oQ -> ...) shows a highly repetitive pattern involving removeChild calls, which also trigger Recalculate style. Both branches include calls that eventually lead to setTimeout, suggesting deferred work, likely related to analytics or other asynchronous tasks.

Performance Quantification:

• The selected Function call took 148.9ms to execute, with 23.6ms spent directly within the function itself.
• This callframe accounts for almost the entire duration of the Run microtasks phase (148.9ms out of 149.9ms) and represents a substantial part of the total Event: click duration (148.9ms out of 257.8ms).
• Potential bottlenecks are evident in its descendants:
  • A significant portion (50.4ms) is spent in a path involving CSS processing (css, renderRule, _renderStyleToClassNames), with 30ms self time in _renderStyleToClassNames.
  • A highly repetitive sequence of calls (oK -> oQ -> ...) culminates in frequent removeChild operations and subsequent Recalculate style events. While each individual removeChild or Recalculate style is relatively short (around 2-4ms), their repeated execution contributes significantly to the overall time.

Suggestions for Improvement:

• Investigate the CSS processing path (css, renderRule, _renderStyleToClassNames). If using a CSS-in-JS library, ensure styles are efficiently generated and applied, avoiding redundant work or excessive runtime style computation.
• Analyze the code responsible for the repetitive removeChild calls. This pattern strongly suggests inefficient DOM manipulation. Look for loops or recursive functions that are repeatedly adding or removing elements. Batching DOM updates (e.g., building a fragment and appending it once) or using techniques that minimize DOM manipulation and style recalculations can drastically improve performance.
• Review the analytics tracking implementation (indicated by the presence of multiple Google Tag Manager URLs). Ensure tracking calls are asynchronous and non-blocking where possible, especially within critical user interaction paths like click handlers. The repeated setTimeout calls originating from these scripts suggest some work is deferred, but the initial synchronous execution is still costly.