Papers › Prefix-Tuning: Optimizing Continuous Prompts for Generation

Prefix-Tuning: Optimizing Continuous Prompts for Generation

1 Jan 2021ACL 2021 5arXiv:2101.00190archive 2025-07-28

Xiang Lisa Li, Percy Liang

Fine-tuning is the de facto way to leverage large pretrained language models to perform downstream tasks. However, it modifies all the language model parameters and therefore necessitates storing a full copy for each task. In this paper, we propose prefix-tuning, a lightweight alternative to fine-tuning for natural language generation tasks, which keeps language model parameters frozen, but optimizes a small continuous task-specific vector (called the prefix). Prefix-tuning draws inspiration from prompting, allowing subsequent tokens to attend to this prefix as if it were "virtual tokens". We apply prefix-tuning to GPT-2 for table-to-text generation and to BART for summarization. We find that by learning only 0.1\% of the parameters, prefix-tuning obtains comparable performance in the full data setting, outperforms fine-tuning in low-data settings, and extrapolates better to examples with topics unseen during training.

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Code

Syntology Ran 4 of 6 code samples harvested from 1 repository linked to this paper; 2 have no recorded run. Of those that ran: 2 ran · our draft was wrong; 2 ran with no contract checked.

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13 repositories listed; official and paper-mentioned ones first.

DKhomi/PrefixTuning mentioned on GitHub report
NVIDIA/FasterTransformer mentioned on GitHubpytorchApache-2.0 report
ga642381/SpeechPrompt mentioned on GitHubpytorch report
hellokevin07/elastictrainer mentioned on GitHubtfMIT report
jordiclive/ControlPrefixes mentioned on GitHubpytorch report
lostoxygen/llm-confidentiality mentioned on GitHubpytorchApache-2.0 report
niyunsheng/ems-sd mentioned on GitHubpytorchApache-2.0 report
ranggihwang/pregated_moe mentioned on GitHubpytorch report
rmokady/clip_prefix_caption mentioned on GitHubpytorchMIT report
teticio/llama-squad mentioned on GitHubpytorchGPL-3.0 report
thudm/swissarmytransformer mentioned on GitHubpytorch report

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6 samples harvested; 4 ran; 0 honoured the contract we drafted; 2 have no recorded run. Read from Syntology's graph 2026-09-24; that is when this build read the record, not when the samples ran.

2ran · our draft was wrong
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BaseMixin thudm/swissarmytransformer/sat/model/finetune/prompt_tuning.py community (archive-listed) ran · metamorphic tier: deterministic Apache-2.0 (permissive) · 6b7c651bf334e2be · report
PrefixTuningMixin thudm/swissarmytransformer/sat/model/finetune/prompt_tuning.py community (archive-listed) ran · metamorphic tier: deterministic Apache-2.0 (permissive) · e5740cff266d5a5d · report
non_conflict thudm/swissarmytransformer/sat/model/finetune/prompt_tuning.py community (archive-listed) ran · our draft was wrong Apache-2.0 (permissive) · 3823a93a9e064f82 · report
replacable thudm/swissarmytransformer/sat/model/finetune/prompt_tuning.py community (archive-listed) ran · our draft was wrong Apache-2.0 (permissive) · 7ede45f27f0943d8 · report
attention_fn_default thudm/swissarmytransformer/sat/model/finetune/prompt_tuning.py community (archive-listed) unverified Apache-2.0 (permissive) · 844b89380ab187e6 · report
standard_attention thudm/swissarmytransformer/sat/model/finetune/prompt_tuning.py community (archive-listed) unverified Apache-2.0 (permissive) · 82481205cb7b429d · report

Tasks

Language ModelingLanguage ModellingTable-to-Text GenerationText Generation

Results from the paper archive 2025-07-28

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Methods

AdamAttentionAttention DropoutBARTBPECosine AnnealingDense ConnectionsDiscriminative Fine-TuningDropoutGPT-2Layer NormalizationLinear LayerLinear Warmup With Cosine AnnealingMulti-Head AttentionResidual ConnectionSoftmaxWeight Decay

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