Why ChatGPT Can Respond So Fast (It’s Not the Model)

ChatGPT doesn’t “rethink” your entire conversation every time you press enter, and that’s why it feels instant. In this video, we break down KV Cache (Key–Value Cache), the critical inference optimization that makes modern Large Language Models fast enough for real-time chat. You’ll see how Transformers reuse past computations, why generation would be painfully slow without caching, and how this single idea changes the complexity of inference entirely. We cover: - Why naïve attention recomputation is prohibitively expensive - How autoregressive generation really works token by token…