Publisher Summary The Junior instruction set is based on fundamental coperators, the language most frequently used for behavior modeling of embedded systems. This simple DSP processor is named Junior, and is only a preliminary one with obvious weaknesses. Therefore, the identified weakness of Junior can be used to guide the further learning. After carefully benchmarking DSP kernel algorithms using the junior instruction set, it will be realized why the Junior instruction set cannot give enough performance. The lesson learned during the design of Junior is used as input knowledge to design a more qualified instruction set, Senior. Most DSP behavior models (the source codes of applications) are based on the C language. The Junior instruction set intuitively resembles the primitive operators of C. It is found that what is missing of the instruction set just from the mapping of C-primitive operators. The missing parts or weaknesses of Junior are identified after benchmarking the junior instruction set. The weaknesses identified are used to promote the quality of DSP processor design.