For most games shader generation takes only a few milliseconds, but for a few demanding titles, the shaders that they generate are so large that they can result in noticeable stuttering, in severe cases pauses of over a second may occur.
Shaders have to be generated though, and since GC/Wii games are not designed to create shaders ahead of time as a PC game would, when a new effect appears Dolphin has to delay the CPU thread while the GPU thread performs the compilation a pause that does not exist on the consoles. Modern computers and mobile systems do not work in this way, requiring the use of shaders as an intermediary so your system's GPU can perform the tasks that the GC and Wii GPU performed directly. The GC and Wii have no concept of shaders - everything is executed directly by the hardware without an intermediate programming language (API). Star Wars Rogue Squadron II: Rogue Leader is one of the most susceptible titles to shader compilation stuttering.
The second of three games in the Rogue Squadron series, it was published by LucasArts and released as a launch title for the Nintendo GameCube. Star Wars Rogue Squadron II: Rogue Leader is an arcade-style flight action game co-developed by Factor 5 and LucasArts. Star Wars Rogue Squadron II: Rogue Leader