Introduction to Reinforcement Learning - Distributed RL Systems - Lecture 9

Explore the ninth lecture in a course on reinforcement learning, focusing on distributed systems in RL. Delve into the foundations of system architecture, properties of distributed systems, and various approaches to updating model parameters. Examine case studies including MapReduce, DisBeliefF, and AlexNet, and learn about the development of distributed RL systems from Deep Q Network to modern implementations like A3C and IMPALA. Investigate parallelizable algorithms, system designs for AI in modern games like AlphaGo Zero and AlphaStar, and gain insights into the evolution of distributed reinforcement learning architectures.

Intro
Today's Outline
System and architecture are the foundation
Properties of Distributed Systems
MIT EECS 6.824 Distributed Systems
Updating Model Parameters
Synchronous Update versus Asynchronous Update
Decentralized Asynchronous Stochastic Gradient Descend
Parallelism in Distributed ML Systems
Hogwild: Lock-free asynchronous SGD
Implementation of Hogwild (asych SGD) in PyTorch
Case Study: MapReduce
Case Study: DisBelief
Fun facts about Jeff Dean
Case Study: AlexNet
Diagram of Reinforcement Learning
Development of Distributed RL Systems
2013: Deep Q Network
2015: General Reinforcement Learning Architecture (GORILA)
Review on Actor-Critic Methods
A3C: Asynchronous Advantage Actor Critic (ABC)
Comparison to Variants of DQN and GORILA
Sample code for A3C
Why Asynchronism works in A3C?
Comparison of A3C and A2C
Sample code for A2C
2018: Apex-X (Distributed Prioritized Experience Replay)
2018: IMPALA (Importance Weighted Actor- Learner Architecture)
2018 RLlib: abstraction for distributed RL
Some Other Parallelizable Algorithms: (Revisited) Evolution Strategies
Case Study: Al for Modern Games
System Design for AlphaGo Zero
System Design for AlphaStar
Conclusion