User Guides
User Guides#
This section explains how to use Ray’s key concepts to build distributed applications.
If you’re brand new to Ray, we recommend starting with the walkthrough.
- Tasks
- Actors
- Specifying required resources
- Calling the actor
- Passing Around Actor Handles
- Scheduling
- Fault Tolerance
- FAQ: Actors, Workers and Resources
- More about Ray Actors
- Objects
- Environment Dependencies
- Concepts
- Preparing an environment using the Ray Cluster launcher
- Runtime environments
- Remote URIs
- Hosting a Dependency on a Remote Git Provider: Step-by-Step Guide
- Debugging
- Scheduling
- Fault Tolerance
- Design Patterns & Anti-patterns
- Pattern: Using nested tasks to achieve nested parallelism
- Pattern: Using generators to reduce heap memory usage
- Pattern: Using ray.wait to limit the number of pending tasks
- Pattern: Using resources to limit the number of concurrently running tasks
- Pattern: Using an actor to synchronize other tasks and actors
- Pattern: Using a supervisor actor to manage a tree of actors
- Pattern: Using pipelining to increase throughput
- Anti-pattern: Returning ray.put() ObjectRefs from a task harms performance and fault tolerance
- Anti-pattern: Calling ray.get in a loop harms parallelism
- Anti-pattern: Calling ray.get unnecessarily harms performance
- Anti-pattern: Processing results in submission order using ray.get increases runtime
- Anti-pattern: Fetching too many objects at once with ray.get causes failure
- Anti-pattern: Over-parallelizing with too fine-grained tasks harms speedup
- Anti-pattern: Redefining the same remote function or class harms performance
- Anti-pattern: Passing the same large argument by value repeatedly harms performance
- Anti-pattern: Closure capturing large objects harms performance
- Anti-pattern: Using global variables to share state between tasks and actors
- Advanced Topics