10.9 Tracing processing time

The -dtime-trace-file option causes LilyPond to log its internal processing in Google’s Trace Event Format, also known as Chrome tracing format. The resulting JSON file can be displayed as a timeline chart using a viewer such as https://ui.perfetto.dev/.

The time-trace log includes many significant events during initialization, parsing, and output. Other events may be added following existing uses of tracer_global.