Slimes and Magma Cubes Occasionally Jump Frame By Frame

I expected slimes to jump smoothly, and without any problems.

Instead, the slimes were jumping very choppy-like, stopping every half-second or so. Every once and a while, they would jump normally again, before reverting to jumping choppily. This happened even when I set my render distance to 2 chunks (causing my FPS to jump to over 200).

1. Open Minecraft
2. Make a new Creative World
3. Take a "Spawn Slime" or "Spawn Magma Cube" Egg
4. Create a Slime or Magma Cube, and observe how they jump