Papers › Gradient Surgery for Multi-Task Learning

Gradient Surgery for Multi-Task Learning

19 Jan 2020NeurIPS 2020 12arXiv:2001.06782archive 2025-07-28

Tianhe Yu, Saurabh Kumar, Abhishek Gupta, Sergey Levine, Karol Hausman, Chelsea Finn

While deep learning and deep reinforcement learning (RL) systems have demonstrated impressive results in domains such as image classification, game playing, and robotic control, data efficiency remains a major challenge. Multi-task learning has emerged as a promising approach for sharing structure across multiple tasks to enable more efficient learning. However, the multi-task setting presents a number of optimization challenges, making it difficult to realize large efficiency gains compared to learning tasks independently. The reasons why multi-task learning is so challenging compared to single-task learning are not fully understood. In this work, we identify a set of three conditions of the multi-task optimization landscape that cause detrimental gradient interference, and develop a simple yet general approach for avoiding such interference between task gradients. We propose a form of gradient surgery that projects a task's gradient onto the normal plane of the gradient of any other task that has a conflicting gradient. On a series of challenging multi-task supervised and multi-task RL problems, this approach leads to substantial gains in efficiency and performance. Further, it is model-agnostic and can be combined with previously-proposed multi-task architectures for enhanced performance.

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Syntology Ran 7 of 10 code samples harvested from 8 repositories linked to this paper; 3 have no recorded run. Of those that ran: 1 ran · our draft was wrong; 6 ran with no contract checked.

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

tianheyu927/PCGrad officialmentioned in papermentioned on GitHubtf report
OrthoDex/PCGrad-PyTorch mentioned on GitHubpytorch report
WeiChengTseng/Pytorch-PCGrad mentioned on GitHubpytorch report
avivnavon/nash-mtl mentioned on GitHubpytorch report
cranial-xix/famo mentioned on GitHubpytorch report
grtzsohalf/SpeechNet-codebase mentioned on GitHubpytorch report
rangwani-harsh/PC_Grad_Pytorch mentioned on GitHubpytorch report
torchjd/torchjd mentioned on GitHubpytorch report
pwc-1/Paper-9 mindspore report
pwc-1/Paper-9 mindspore report

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10 samples harvested; 7 ran; 0 honoured the contract we drafted; 3 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.

1ran · our draft was wrong
6ran
3unverified

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PCGrad tianheyu927/PCGrad/PCGrad_tf.py official repository unverified MIT (permissive) · a64df2e1bec39655 · report
PCGrad grtzsohalf/SpeechNet-codebase/src/pcgrad.py community (archive-listed) ran MIT (permissive) · 16a092a4692eb73d · report
PCGrad WeiChengTseng/Pytorch-PCGrad/pcgrad.py community (archive-listed) ran BSD-3-Clause (permissive) · 5e1ac35b4889d3d9 · report
PCGrad cranial-xix/famo/methods/weight_methods.py community (archive-listed) ran MIT (permissive) · 31aa3418224baf69 · report
PCGrad avivnavon/nash-mtl/methods/weight_methods.py community (archive-listed) ran no licence file found · pointer only · c34a09ae701d0f40 · report
WeightMethod cranial-xix/famo/methods/weight_methods.py community (archive-listed) ran MIT (permissive) · 654cdad96608431e · report
WeightMethod avivnavon/nash-mtl/methods/weight_methods.py community (archive-listed) ran no licence file found · pointer only · 9b136fce78a21563 · report
pc_grad_update OrthoDex/PCGrad-PyTorch/pcgrad.py community (archive-listed) ran · our draft was wrong MIT (permissive) · 4cf729e96cf2c9fe · report
PCGrad_backward wgchang/PCGrad-pytorch-example/pcgrad-example.py community (archive-listed) unverified no licence file found · pointer only · 0b13eb7dd654266c · report
PCGrad_loss rangwani-harsh/PC_Grad_Pytorch/pc_grad_pytorch.py community (archive-listed) unverified no licence file found · pointer only · 3e75577924697c22 · report

Tasks

Deep Reinforcement LearningImage ClassificationMulti-Task LearningReinforcement LearningReinforcement Learning (RL)image-classification

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