ractor

A ractor is a conceptual unit of computation that allows for concurrent execution of tasks within a program. It is designed to facilitate parallel processing by providing a mechanism for isolating state and communication between these independent units. Unlike traditional threads that share memory, ractors typically have their own private memory space, which helps to prevent data races and simplifies concurrent programming by enforcing explicit communication patterns.

The core idea behind ractors is to offer a more robust and manageable approach to concurrency than traditional threading models. By enforcing that each ractor has its own memory, developers are encouraged to think about how data is shared and passed between concurrent tasks. This often involves message-passing, where ractors communicate by sending and receiving data structures. This explicit communication model can make it easier to reason about the behavior of concurrent programs and debug issues that arise from shared mutable state.

Implementations of ractors can vary across programming languages and runtimes. Some systems may treat ractors as very lightweight processes, while others might map them to underlying operating system threads with specific isolation guarantees. The goal is always to achieve safe and efficient concurrency by managing the execution and state of independent computational units. This approach aims to improve performance by leveraging multi-core processors and to enhance the reliability of applications that require concurrent operations.