Omango

This is a concurrency collection.

• Support lock-free SPSC and MPMC queue (bounded and unbounded). The queues are simple, lightweight, fast and safe in multithreading environment. It is faster than std::mpsc::sync_channel and other open source's bounded queue ( ringbuf, rtrb, flume, crossbeam-channel ).

• Support Golang WaitGroup waits for a collection of threads to finish.

• Support Single Flight multiplexing threads that have the same work and only one represent thread will run and returns response for all waiting threads.

• Support Single Source provide mechanism to synthesize response from multiple sources.

Table of Contents

• Introduction
• Usage
• Compatibility
• Benchmarks
• License
• Reference

Introduction

Both SPSC and MPMC queue are implemented based on pseudocode of Dmitry Vyukov. The implementation way is exactly the same. But there are still some differences between them about wait-retry and blocking.

MPMC is high contention multithreading environment. If the retry is continuous and immediate, the CPU cache coherence will be increased rapidly and decrease performance. Therefore, we must wait then retry. However, this thing is unsuitable in SPSC is lower contention multithreading environment (Just 2 threads). In SPSC, the immediate retry still guarantees performance.

Both SPSC and MPMC queue can be used as channels.

Compared with version 0.1.*

• Performance is better.

• Supported unbounded queues (SPSC + MPMC).

• Can use recv to get remaining items when the queue was closed.

Usage

Add this to your Cargo.toml:

[dependencies]
omango = "0.2.6"

Compatibility

The minimum supported Rust version is 1.57.

Benchmarks

Tests were performed on an Intel Core I7 with 4 cores running Windows 11 and M1 with 8 cores running macOS BigSur 11.3.

License

The crate is licensed under the terms of the MIT license. See LICENSE for more information.

Reference

• Crossbeam-Channel
• Blog of Dmitry Vyukov
• The cache coherence protocols
• CppCon 2017: C++ atomics, from basic to advanced
• Golang SingleFlight
• Golang WaitGroup