How to Use go tool trace for Execution Tracing

Use the go tool trace command to visualize execution traces generated by runtime/trace.

1. Generate a trace file by running your program with the GODEBUG environment variable set to enable tracing, or by importing runtime/trace and calling trace.Start(os.Stdout).
2. Convert the trace output to a visual format by piping it to go tool trace.

GODEBUG=trace=1 ./your-program > trace.out
go tool trace trace.out

The command opens an interactive web interface in your default browser to analyze goroutine scheduling, GC pauses, and system calls.

go tool trace turns raw execution logs from your Go program into an interactive visual timeline. It helps you see exactly when your code is running, waiting, or pausing for garbage collection. Think of it as a video recording of your program's internal activity that you can play back to find performance bottlenecks.