VANILLA SPEC DECODING (2023)
Draft LLM
separate small model
guesses from scratch [draft tokens] [target verifies]
EAGLE-3
TARGET MODEL
low mid high Fuse → Draft Layer
Target LM Head
[draft tokens]
draft reuses target features

TRAINING-TIME TEST
without
training teaches step 1 only. at step 2 the draft consumes its own step-1 output, a distribution it never saw
→ acceptance collapses
with
during training the draft unrolls several steps and consumes its own outputs → training distribution = inference distribution
→ more data, longer acceptance