# Efficient Transformers in Reinforcement Learning using Actor-Learner Distillation

arXiv: https://arxiv.org/abs/2104.01655 · HTML: https://mlsanity.com/paper/2104.01655/

## Key facts

- Cited by 35 papers in the map (data through 14 Oct 2026).
- Builds on 30 of its 36 references that are in the map.
- First posted on arXiv 4 Apr 2021.

## Builds on (most cited first, 30 of 30)

- [Attention Is All You Need](https://mlsanity.com/paper/1706.03762/) (2017)
- [BERT: Pre-training of Deep Bidirectional Transformers for Language Understanding](https://mlsanity.com/paper/1810.04805/) (2018)
- [Language Models are Few-Shot Learners](https://mlsanity.com/paper/2005.14165/) (2020)
- [Proximal Policy Optimization Algorithms](https://mlsanity.com/paper/1707.06347/) (2017)
- [Distilling the Knowledge in a Neural Network](https://mlsanity.com/paper/1503.02531/) (2015)
- [Asynchronous Methods for Deep Reinforcement Learning](https://mlsanity.com/paper/1602.01783/) (2016)
- [Generating Long Sequences with Sparse Transformers](https://mlsanity.com/paper/1904.10509/) (2019)
- [IMPALA: Scalable Distributed Deep-RL with Importance Weighted Actor-Learner Architectures](https://mlsanity.com/paper/1802.01561/) (2018)
- [Efficient Transformers: A Survey](https://mlsanity.com/paper/2009.06732/) (2020)
- [Compressive Transformers for Long-Range Sequence Modelling](https://mlsanity.com/paper/1911.05507/) (2019)
- [Born Again Neural Networks](https://mlsanity.com/paper/1805.04770/) (2018)
- [Do Deep Nets Really Need to be Deep?](https://mlsanity.com/paper/1312.6184/) (2013)
- [Policy Distillation](https://mlsanity.com/paper/1511.06295/) (2015)
- [Population Based Training of Neural Networks](https://mlsanity.com/paper/1711.09846/) (2017)
- [Maximum a Posteriori Policy Optimisation](https://mlsanity.com/paper/1806.06920/) (2018)
- [Stabilizing Transformers for Reinforcement Learning](https://mlsanity.com/paper/1910.06764/) (2019)
- [Asymmetric Actor Critic for Image-Based Robot Learning](https://mlsanity.com/paper/1710.06542/) (2017)
- [Distral: Robust Multitask Reinforcement Learning](https://mlsanity.com/paper/1707.04175/) (2017)
- [Actor-Mimic: Deep Multitask and Transfer Reinforcement Learning](https://mlsanity.com/paper/1511.06342/) (2015)
- [Funnel-Transformer: Filtering out Sequential Redundancy for Efficient Language Processing](https://mlsanity.com/paper/2006.03236/) (2020)
- [Multi-task Deep Reinforcement Learning with PopArt](https://mlsanity.com/paper/1809.04474/) (2018)
- [Large Memory Layers with Product Keys](https://mlsanity.com/paper/1907.05242/) (2019)
- [Phasic Policy Gradient](https://mlsanity.com/paper/2009.04416/) (2020)
- [V-MPO: On-Policy Maximum a Posteriori Policy Optimization for Discrete and Continuous Control](https://mlsanity.com/paper/1909.12238/) (2019)
- [Meta reinforcement learning as task inference](https://mlsanity.com/paper/1905.06424/) (2019)
- [Transferring Inductive Biases through Knowledge Distillation](https://mlsanity.com/paper/2006.00555/) (2020)
- [Mix&Match - Agent Curricula for Reinforcement Learning](https://mlsanity.com/paper/1806.01780/) (2018)
- [Progressive Reinforcement Learning with Distillation for Multi-Skilled Motion Control](https://mlsanity.com/paper/1802.04765/) (2018)
- [Scalable Syntax-Aware Language Models Using Knowledge Distillation](https://mlsanity.com/paper/1906.06438/) (2019)
- [IMPACT: Importance Weighted Asynchronous Architectures with Clipped Target Networks](https://mlsanity.com/paper/1912.00167/) (2019)

## Built on by (most cited first, 30 of 35)

- [Offline Reinforcement Learning as One Big Sequence Modeling Problem](https://mlsanity.com/paper/2106.02039/) (2021)
- [TransDreamer: Reinforcement Learning with Transformer World Models](https://mlsanity.com/paper/2202.09481/) (2022)
- [Structured State Space Models for In-Context Reinforcement Learning](https://mlsanity.com/paper/2303.03982/) (2023)
- [Going Beyond Linear Transformers with Recurrent Fast Weight Programmers](https://mlsanity.com/paper/2106.06295/) (2021)
- [The State of Sparse Training in Deep Reinforcement Learning](https://mlsanity.com/paper/2206.10369/) (2022)
- [A Survey on Transformers in Reinforcement Learning](https://mlsanity.com/paper/2301.03044/) (2023)
- [History Compression via Language Models in Reinforcement Learning](https://mlsanity.com/paper/2205.12258/) (2022)
- [On Transforming Reinforcement Learning by Transformer: The Development Trajectory](https://mlsanity.com/paper/2212.14164/) (2022)
- [Attention Mechanism in Neural Networks: Where it Comes and Where it Goes](https://mlsanity.com/paper/2204.13154/) (2022)
- [Deep Generative Models for Offline Policy Learning: Tutorial, Survey, and Perspectives on Future Directions](https://mlsanity.com/paper/2402.13777/) (2024)
- [Towards Deeper Deep Reinforcement Learning with Spectral Normalization](https://mlsanity.com/paper/2106.01151/) (2021)
- [Semantic HELM: A Human-Readable Memory for Reinforcement Learning](https://mlsanity.com/paper/2306.09312/) (2023)
- [Memory Gym: Towards Endless Tasks to Benchmark Memory Capabilities of Agents](https://mlsanity.com/paper/2309.17207/) (2023)
- [Kernel Identification Through Transformers](https://mlsanity.com/paper/2106.08185/) (2021)
- [Switch Trajectory Transformer with Distributional Value Approximation for Multi-Task Reinforcement Learning](https://mlsanity.com/paper/2203.07413/) (2022)
- [AGaLiTe: Approximate Gated Linear Transformers for Online Reinforcement Learning](https://mlsanity.com/paper/2310.15719/) (2023)
- [Grounded Answers for Multi-agent Decision-making Problem through Generative World Model](https://mlsanity.com/paper/2410.02664/) (2024)
- [Data augmentation for efficient learning from parametric experts](https://mlsanity.com/paper/2205.11448/) (2022)
- [Spatially-Aware Transformer for Embodied Agents](https://mlsanity.com/paper/2402.15160/) (2024)
- [Imagine, Initialize, and Explore: An Effective Exploration Method in Multi-Agent Reinforcement Learning](https://mlsanity.com/paper/2402.17978/) (2024)
- [Uncertainty Representations in State-Space Layers for Deep Reinforcement Learning under Partial Observability](https://mlsanity.com/paper/2409.16824/) (2024)
- [Improving Sample Efficiency of Value Based Models Using Attention and Vision Transformers](https://mlsanity.com/paper/2202.00710/) (2022)
- [Multi-Agent Reinforcement Learning with Hierarchical Coordination for Emergency Responder Stationing](https://mlsanity.com/paper/2405.13205/) (2024)
- [Optimal Return-to-Go Guided Decision Transformer for Auto-Bidding in Advertisement](https://mlsanity.com/paper/2506.21956/) (2025)
- [Empowering Clinicians with Medical Decision Transformers: A Framework for Sepsis Treatment](https://mlsanity.com/paper/2407.19380/) (2024)
- [Advances in Transformers for Robotic Applications: A Review](https://mlsanity.com/paper/2412.10599/) (2024)
- [Deep Generative Models for Decision-Making and Control](https://mlsanity.com/paper/2306.08810/) (2023)
- [Mixture of Weight-shared Heterogeneous Group Attention Experts for Dynamic Token-wise KV Optimization](https://mlsanity.com/paper/2506.13541/) (2025)
- [VariBASed: Variational Bayes-Adaptive Sequential Monte-Carlo Planning for Deep Reinforcement Learning](https://mlsanity.com/paper/2602.18857/) (2026)
- [Multi-Task Learning for User Engagement and Adoption in Live Video Streaming Events](https://mlsanity.com/paper/2106.10305/) (2021)

## Abstract (arXiv)

Many real-world applications such as robotics provide hard constraints on power and compute that limit the viable model complexity of Reinforcement Learning (RL) agents. Similarly, in many distributed RL settings, acting is done on un-accelerated hardware such as CPUs, which likewise restricts model size to prevent intractable experiment run times. These "actor-latency" constrained settings present a major obstruction to the scaling up of model complexity that has recently been extremely successful in supervised learning. To be able to utilize large model capacity while still operating within the limits imposed by the system during acting, we develop an "Actor-Learner Distillation" (ALD) procedure that leverages a continual form of distillation that transfers learning progress from a large capacity learner model to a small capacity actor model. As a case study, we develop this procedure in the context of partially-observable environments, where transformer models have had large improvements over LSTMs recently, at the cost of significantly higher computational complexity. With transformer models as the learner and LSTMs as the actor, we demonstrate in several challenging memory environments that using Actor-Learner Distillation recovers the clear sample-efficiency gains of the transformer learner model while maintaining the fast inference and reduced total training time of the LSTM actor model.
