Cave Story - extremely slow!

[ArkBlitz]

Hello! I've been using Dolphin not too long ago. I've been trying to play Cave Story on the emulator, but it's so extremely slow that it doesn't even boot! The farthest I've been able to go is the intro screen. The speed averages 20%, sometimes just 8%. I'm using Dolphin for Ubuntu, using the recommendations for speeding up I found here. I find it very strange that a simple 2D game has such a slow speed in an emulator.