presto-main/src/main/java/io/prestosql/execution/SqlStageExecution.java/SqlStageExecution/getTotalCpuTime
class SqlStageExecution:    public synchronized Duration getTotalCpuTime()
    {
        long millis = getAllTasks().stream()
                .mapToLong(task -> task.getTaskInfo().getStats().getTotalCpuTime().toMillis())
                .sum();
        return new Duration(millis, TimeUnit.MILLISECONDS);
    }