Responsive Multithreaded Processor (RMTP) has the Simultaneous Multithreading (SMT) architecture with priority for distributed real-time processings, called prioritized SMT architecture. In RMTP, execution efficiencies of tasks executing in threads except the highest priority thread fluctuate by multiple combinations of tasks executing simultaneously. Therefore, it is difficult to guarantee the schedulability of tasks. Many real-time scheduling algorithms having only real-time part is not well suited to the prioritized SMT architecture. Because they cannot make use of the remaining times of threads except the highest priority thread. In contrast, semi-fixed-priority scheduling has an optional part which is a non-real-time part and improves the quality of the result so that semi-fixed-priority scheduling is well suited to the prioritized SMT architecture. This paper evaluates the performance of semi-fixed-priority scheduling on prioritized SMT processors. Experimental evaluations show that semi-fixed-priority scheduling is well suited to prioritized SMT processors.