This paper presents the design of a high performance whole-system emulator --- SkyEye. Several optimization methods used in SkyEye are proposed and analyzed. By using novel searching strategy for Translated Block (TB), SkyEye save the time to find proper translated block. SkyEye uses Basic Equal Length Unit (B-ELU) method to implement dynamic binary translation. The performance model of B-ELU is built to get the best length of translated block. In order to further reduce the switch time between executing of translated block and searching for translated block, adaptive block linking (ABL) method is designed. Using these methods, SkyEye which simulates ARM CPU based hardware system achieves marvelous performance in experiments.