Runtime debugging

Table of Contents

• CPU profiling unresponsive window via tracing

CPU profiling unresponsive window via tracing

When a window (renderer process) is unresponsive the devtools might be unable to collect the required cpu profile. A reliable way to profile in such cases is with the tracing infra using the steps below,

• Restart VS Code with the following flags --trace --trace-category-filter="renderer,blink,v8,disabled-by-default-v8.cpu_profiler"
• Once the unresponsive dialog pop ups, click on the Reopen button
• In the new window, execute "F1 > Developer: Stop Tracing"

This will generate a trace json file which can be loaded into any of the following clients that supports the Google's Trace Event format

1. chrome://tracing in any chromium browser
2. ui.perfetto.dev
3. Firefox profiler