# EnvPool: A Highly Parallel Reinforcement Learning Environment Execution Engine

arXiv: https://arxiv.org/abs/2206.10558 · HTML: https://mlsanity.com/paper/2206.10558/

## Key facts

- Cited by 62 papers in the map (data through 14 Oct 2026).
- Builds on 17 of its 46 references that are in the map.
- First posted on arXiv 21 Jun 2022.

## Builds on (most cited first, 17 of 17)

- [Proximal Policy Optimization Algorithms](https://mlsanity.com/paper/1707.06347/) (2017)
- [OpenAI Gym](https://mlsanity.com/paper/1606.01540/) (2016)
- [Mastering Atari, Go, Chess and Shogi by Planning with a Learned Model](https://mlsanity.com/paper/1911.08265/) (2019)
- [Dota 2 with Large Scale Deep Reinforcement Learning](https://mlsanity.com/paper/1912.06680/) (2019)
- [Isaac Gym: High Performance GPU-Based Physics Simulation For Robot Learning](https://mlsanity.com/paper/2108.10470/) (2021)
- [IMPALA: Scalable Distributed Deep-RL with Importance Weighted Actor-Learner Architectures](https://mlsanity.com/paper/1802.01561/) (2018)
- [Mastering Chess and Shogi by Self-Play with a General Reinforcement Learning Algorithm](https://mlsanity.com/paper/1712.01815/) (2017)
- [In-Datacenter Performance Analysis of a Tensor Processing Unit](https://mlsanity.com/paper/1704.04760/) (2017)
- [Ray: A Distributed Framework for Emerging AI Applications](https://mlsanity.com/paper/1712.05889/) (2017)
- [Brax -- A Differentiable Physics Engine for Large Scale Rigid Body Simulation](https://mlsanity.com/paper/2106.13281/) (2021)
- [dm_control: Software and Tasks for Continuous Control](https://mlsanity.com/paper/2006.12983/) (2020)
- [ViZDoom: A Doom-based AI Research Platform for Visual Reinforcement Learning](https://mlsanity.com/paper/1605.02097/) (2016)
- [Acme: A Research Framework for Distributed Reinforcement Learning](https://mlsanity.com/paper/2006.00979/) (2020)
- [Tianshou: a Highly Modularized Deep Reinforcement Learning Library](https://mlsanity.com/paper/2107.14171/) (2021)
- [Sample Factory: Egocentric 3D Control from Pixels at 100000 FPS with Asynchronous Reinforcement Learning](https://mlsanity.com/paper/2006.11751/) (2020)
- [Podracer architectures for scalable Reinforcement Learning](https://mlsanity.com/paper/2104.06272/) (2021)
- [WarpDrive: Extremely Fast End-to-End Deep Multi-Agent Reinforcement Learning on a GPU](https://mlsanity.com/paper/2108.13976/) (2021)

## Built on by (most cited first, 30 of 62)

- [ManiSkill2: A Unified Benchmark for Generalizable Manipulation Skills](https://mlsanity.com/paper/2302.04659/) (2023)
- [CORL: Research-oriented Deep Offline Reinforcement Learning Library](https://mlsanity.com/paper/2210.07105/) (2022)
- [Simplifying Deep Temporal Difference Learning](https://mlsanity.com/paper/2407.04811/) (2024)
- [VMAS: A Vectorized Multi-Agent Simulator for Collective Robot Learning](https://mlsanity.com/paper/2207.03530/) (2022)
- [JaxMARL: Multi-Agent RL Environments and Algorithms in JAX](https://mlsanity.com/paper/2311.10090/) (2023)
- [Jumanji: a Diverse Suite of Scalable Reinforcement Learning Environments in JAX](https://mlsanity.com/paper/2306.09884/) (2023)
- [XLand-MiniGrid: Scalable Meta-Reinforcement Learning Environments in JAX](https://mlsanity.com/paper/2312.12044/) (2023)
- [Pgx: Hardware-Accelerated Parallel Game Simulators for Reinforcement Learning](https://mlsanity.com/paper/2303.17503/) (2023)
- [Gymnasium: A Standard Interface for Reinforcement Learning Environments](https://mlsanity.com/paper/2407.17032/) (2024)
- [CaRL: Learning Scalable Planning Policies with Simple Rewards](https://mlsanity.com/paper/2504.17838/) (2025)
- [Learning Humanoid Locomotion over Challenging Terrain](https://mlsanity.com/paper/2410.03654/) (2024)
- [PufferLib: Making Reinforcement Learning Libraries and Environments Play Nice](https://mlsanity.com/paper/2406.12905/) (2024)
- [Planning in a recurrent neural network that plays Sokoban](https://mlsanity.com/paper/2407.15421/) (2024)
- [NAVIX: Scaling MiniGrid Environments with JAX](https://mlsanity.com/paper/2407.19396/) (2024)
- [Open RL Benchmark: Comprehensive Tracked Experiments for Reinforcement Learning](https://mlsanity.com/paper/2402.03046/) (2024)
- [Sample-Efficient Alignment for LLMs](https://mlsanity.com/paper/2411.01493/) (2024)
- [The Impact of On-Policy Parallelized Data Collection on Deep Reinforcement Learning Networks](https://mlsanity.com/paper/2506.03404/) (2025)
- [A Review of Nine Physics Engines for Reinforcement Learning Research](https://mlsanity.com/paper/2407.08590/) (2024)
- [Learning Massively Multitask World Models for Continuous Control](https://mlsanity.com/paper/2511.19584/) (2025)
- [RL-X: A Deep Reinforcement Learning Library (not only) for RoboCup](https://mlsanity.com/paper/2310.13396/) (2023)
- [Cleanba: A Reproducible and Efficient Distributed Reinforcement Learning Platform](https://mlsanity.com/paper/2310.00036/) (2023)
- [Hadamax Encoding: Elevating Performance in Model-Free Atari](https://mlsanity.com/paper/2505.15345/) (2025)
- [Pretraining the Vision Transformer using self-supervised methods for vision based Deep Reinforcement Learning](https://mlsanity.com/paper/2209.10901/) (2022)
- [GEAR: A GPU-Centric Experience Replay System for Large Reinforcement Learning Models](https://mlsanity.com/paper/2310.05205/) (2023)
- [Mitigating Information Loss in Tree-Based Reinforcement Learning via Direct Optimization](https://mlsanity.com/paper/2408.08761/) (2024)
- [Octax: Accelerated CHIP-8 Arcade Environments for Reinforcement Learning in JAX](https://mlsanity.com/paper/2510.01764/) (2025)
- [Emergence of Exploration in Policy Gradient Reinforcement Learning via Retrying](https://mlsanity.com/paper/2606.00151/) (2026)
- [RLtools: A Fast, Portable Deep Reinforcement Learning Library for Continuous Control](https://mlsanity.com/paper/2306.03530/) (2023)
- [HyperPPO: A scalable method for finding small policies for robotic control](https://mlsanity.com/paper/2309.16663/) (2023)
- [Advancing Investment Frontiers: Industry-grade Deep Reinforcement Learning for Portfolio Optimization](https://mlsanity.com/paper/2403.07916/) (2024)

## Abstract (arXiv)

There has been significant progress in developing reinforcement learning (RL) training systems. Past works such as IMPALA, Apex, Seed RL, Sample Factory, and others, aim to improve the system's overall throughput. In this paper, we aim to address a common bottleneck in the RL training system, i.e., parallel environment execution, which is often the slowest part of the whole system but receives little attention. With a curated design for paralleling RL environments, we have improved the RL environment simulation speed across different hardware setups, ranging from a laptop and a modest workstation, to a high-end machine such as NVIDIA DGX-A100. On a high-end machine, EnvPool achieves one million frames per second for the environment execution on Atari environments and three million frames per second on MuJoCo environments. When running EnvPool on a laptop, the speed is 2.8x that of the Python subprocess. Moreover, great compatibility with existing RL training libraries has been demonstrated in the open-sourced community, including CleanRL, rl_games, DeepMind Acme, etc. Finally, EnvPool allows researchers to iterate their ideas at a much faster pace and has great potential to become the de facto RL environment execution engine. Example runs show that it only takes five minutes to train agents to play Atari Pong and MuJoCo Ant on a laptop. EnvPool is open-sourced at https://github.com/sail-sg/envpool.
