← All IntelClip / EntertainmentDiffusion LLMs generate drafts, not tokens
From Why LLM Inference Is Memory-Bound (Julia Turc) · ≈16:08
“They no longer generate one token at a time, but rather one draft at a time.”
“They start with a fixed context window of complete nonsense and iteratively clean it up into a coherent response.”
“More iterations take more time, but also improve the response.”
What’s in it
- Understand how diffusion LLMs generate whole drafts, not one token at a time
- See the speed-quality tradeoff controlled by iteration count
- Learn when diffusion beats autoregressive on total iterations
Clip transcript
Pushing this idea to the limit, why not have it deal with all of the output tokens in parallel? If you've been watching my channel for a while, you know where this is going. Diffusion LLMs do exactly that. As you already know, auto-regressive LLMs generate one token at a time until the end of sequence is produced, or a maximum token count is reached. So the number of iterations is dynamically determined by the model for each prompt. Diffusion LLMs are a completely new paradigm. They no longer generate one token at a time, but rather one draft at a time. They start with a fixed context window of complete nonsense and iteratively clean it up into a coherent response. Similar to auto-regressive models, they're still sequential. Each draft needs to wait for the completion of the previous one. However, they perform a fixed number of iterations. This is a hyper parameter that acts as a knob between speed and quality. More iterations take more time, but also improve the response. In a previous video, I covered ways of bringing this number down to tens or hundreds without compromising the final output. For an average LLM response with a few thousand output tokens, a diffusion model will perform fewer iterations than a traditional one. But of course, in case of a yes or no answer, the diffusion chain is longer.
Comments
Sign in to comment.
Loading comments…