Dynamic Binary Translators and Optimizers (DBTOs) have been established as a hot research topic. They are used in many different systems, such as emulation, instrumentation tools and innovative HW/SW co-designed microarchitectures. Although many researchers worked on characterizing and reducing the emulation overhead, to the best of our knowledge, there are no published results that explain how the microarchitectural behavior of the emulation software is affected by the guest application which is emulated. In this paper we study the DBTO as an independent application, which is divided into the modules with specific functionality. We show the variance in microarchitectural behavior of DBTO among 48 applications. Moreover, we locate and explain the sources of variance. The results show that the variance is caused by interaction with the code cache (emulated application) and non uniform module execution characteristics. The insights presented in this paper can be exploited towards the design of more efficient DBTOs

Peer Reviewed