Mpsc class

MPSC (Multiple-Producer Single-Consumer) channels - The workhorse of concurrent systems.

The most versatile channel type for fan-in patterns where multiple producers send data to a single consumer. Combines thread-safety for concurrent producers with single-consumer optimizations for maximum throughput.

Core Strengths

  • Thread-safe producers: Multiple threads can send concurrently
  • Single-consumer optimization: No consumer-side coordination overhead
  • Rich buffering strategies: Unbounded, bounded, rendezvous, latest-only
  • Advanced drop policies: Handle backpressure with oldest/newest dropping
  • Producer cloning: Create multiple sender handles from one channel
  • Flexible capacity: From 0 (rendezvous) to unlimited (unbounded)

When to Use MPSC

  • Event aggregation: Multiple event sources ↔ single event loop
  • Task queues: Multiple workers ↔ single dispatcher
  • Logging systems: Multiple threads ↔ single log writer
  • UI updates: Multiple components ↔ single UI thread
  • Data collection: Multiple sensors ↔ single processor
  • Request handling: Multiple clients ↔ single server

Performance Characteristics

  • Good throughput: ~535-950ns per operation
  • Latest-only mode: Extremely fast ~7ns per operation for coalescing buffers
  • Memory efficient: Chunked buffers available for unbounded channels
  • Scalable: Designed to handle multiple concurrent producers
  • Efficient design: Optimized for producer-consumer scenarios

Example

{@tool snippet example/mpsc_example.dart} {@end-tool}

Constructors

Mpsc()

Properties

hashCode → int
The hash code for this object.
no setterinherited
runtimeType → Type
A representation of the runtime type of the object.
no setterinherited

Methods

noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
inherited
toString() → String
A string representation of this object.
inherited

Operators

operator ==(Object other) → bool
The equality operator.
inherited

Static Methods

bounded<T>(int capacity, {String? metricsId}) → MpscChannel<T>
channel<T>({int? capacity, DropPolicy policy = DropPolicy.block, OnDrop<T>? onDrop, bool chunked = true, String? metricsId}) → MpscChannel<T>
latest<T>({String? metricsId}) → MpscChannel<T>
unbounded<T>({bool chunked = true, String? metricsId}) → MpscChannel<T>