MOONLIGHT BLADE Online is a 3D MMORPG with exquisite pictures, complex scenes, realistic lighting, gorgeous effect and multiplayer battle of hundreds of players on the same screen, which challenges the memory and frame rate. This session is aimed at introducing how to quickly locate and analyze performance bottlenecks with self-developed performance analysis tools, revealing some of the unique approaches we have adopted to optimize memory significantly and increase the frame rate of midrange graphics card from 20 to 40.