Unity 3D Developer Interview Question:

Which of the following examples will run faster?

1000 GameObjects, each with a MonoBehaviour implementing the Update callback.
One GameObject with one MonoBehaviour with an Array of 1000 classes, each implementing a custom Update() callback?

Submitted by: Muhammad

The correct answer is 2.

The Update callback is called using a C# Reflection, which is significantly slower than calling a function directly. In our example, 1000 GameObjects each with a MonoBehaviour means 1000 Reflection calls per frame.

Creating one MonoBehaviour with one Update, and using this single callback to Update a given number of elements, is a lot faster, due to the direct access to the method.
Submitted by: Muhammad