1. Run V8 with --prof --log-timer-events, or alternatively,
    Chrome with --no-sandbox --js-flags="--prof --log-timer-events" to produce v8.log.
  2. Open v8.log on this page. Don't worry, it won't be uploaded anywhere.
  3. Click "Start" to start number crunching. This will take a while.
  4. Click "Show plot/profile" to switch between the statistical profile and the timeline plot.
    C++ items are missing in the statistical profile because symbol information is not available.
    Consider using the command-line utility instead.
If you expect multiple V8 instances to run concurrently, for example with several tabs in Chrome,
add the V8 flag --logfile=v8.%p.log so that each instance writes to its own log file.