A small draft model proposes tokens, and the main model checks them. What is this technique?
Why C is the answer
Speculative decoding
Accepted drafts save main-model steps, which lowers latency.
In detail
- Accepted drafts save steps on the main model.
- Rejected drafts cost some time.
Use case
An illustrative scenario, not a real incident.
A small model drafts tokens, and the main model confirms them, so fewer full steps are needed.
See it in different ways
flowchart LR A["Queue"] --> B["First token"] B --> C["KV cache reuse"] C --> D["Later tokens"] E["Continuous batching"] --> A
stateDiagram-v2 [*] --> Goal Goal --> Quantization: smaller weights Goal --> Pruning: fewer weights Goal --> Distillation: a smaller student model Goal --> Speculative: fewer main model steps
sequenceDiagram participant P0 as Draft model participant P1 as Main model P0->>P1: Proposed tokens P1-->>P0: Accept or reject
Key point: Speculative decoding saves main-model steps.
Why the other options are wrong
- A. Gradient accumulation across several batches
- That is about training gradients.
- B. Dynamic padding of the input tokens
- That is about inputs.
- D. Knowledge distillation at training time
- Distillation happens in training.

