Pre-research on Chrome DevTools for "Interaction to Next Paint" project and seeking for confirmation

[Chennagiri Tanmai]

Respected Chromium Org Team,

I hope this email finds you well. I have been working on the initial phase of the "Interaction to Next Paint" project and wanted to share some pre-research I’ve done to track performance using Chrome DevTools. I’ve attached two images that capture performance insights:

First Image: Shows the activity timeline during page load, breaking down time spent on scripting, rendering, and event handling.

Second Image: Provides a summary of total execution time, highlighting the contribution of scripting, rendering, and system tasks.

From the analysis, I observed the following key points:

Event: "pointerover" took the longest time at 1,150.9 ms (35.6%), indicating that pointer event handling might need optimization.

Script evaluation accounted for 764.9 ms (23.6%), suggesting that script execution might require investigation.

Total scripting time was 2,502 ms out of 21,269 ms, pointing to significant scripting overhead.

Minor delays were also noted in rendering (302 ms) and painting (130 ms).

I plan to start with basic coding soon and wanted to confirm if this aligns with the expected pre-research at this stage. Are these observations in line with the project’s goals, and would you recommend focusing on any specific aspects before proceeding?

Thank you for your guidance and time. I look forward to hearing from you.

Best regards,

Chennagiri Tanmai Sai