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FFT - Amazon SageMaker AI

FFT

FFT (Full Fine-Tuning) updates all model weights during training. This provides the deepest level of customization but requires more compute resources and longer training time.

When to use FFT

  • Large domain shifts where the model needs fundamental knowledge changes

  • You have a large, high-quality dataset (small datasets risk catastrophic forgetting)

  • You want no adapter overhead at inference time

  • Maximum customization depth is required

Key differences from LoRA

  • No lora_rank, lora_alpha, or merge_weights parameters

  • Adds max_response_length parameter for controlling generated output length

  • Higher compute cost and longer training time

  • Larger output artifacts (full model weights)

  • Not compatible with continuous customization

For the full parameter reference including FFT-specific hyperparameters, see each technique page: SFT, DPO, RFT.