presto-main/src/main/java/io/prestosql/execution/SqlTask.java/SqlTask/TaskHolder
class SqlTask:        private TaskHolder(TaskInfo finalTaskInfo, SqlTaskIoStats finalIoStats)
        {
            this.taskExecution = null;
            this.finalTaskInfo = requireNonNull(finalTaskInfo, "finalTaskInfo is null");
            this.finalIoStats = requireNonNull(finalIoStats, "finalIoStats is null");
        }