Crate ranked_semaphore

Ranked Semaphore - High-Performance Priority Semaphore

A completely safe (zero unsafe) high-performance semaphore implementation with priority queuing. Design goals: zero-cost abstractions, ultra-low latency, minimal memory footprint.

Core Features

• High Performance: Uncontended path <10ns latency
• Zero unsafe: 100% safe Rust code
• Dynamic Priority: Support for arbitrary priority levels
• Zero Cost: Memory allocation only for actively used priorities
• Batch Optimized: Smart batching reduces lock contention
• Cache Friendly: Optimized memory layout

Usage Example

use ranked_semaphore::RankedSemaphore;

// Create a semaphore with 3 permits
let semaphore = RankedSemaphore::new_fifo(3);

// Default priority acquisition
let _permit1 = semaphore.acquire().await?;

// High priority acquisition
let _permit2 = semaphore.acquire_with_priority(10).await?;

// Batch acquisition
let _permits = semaphore.acquire_many_with_priority(5, 2).await?;

Modules

prelude

Prelude module for commonly used types.

Structs

Acquire

Acquire operation Future

AcquireError

Error returned from acquire operations when the semaphore has been closed.

AcquireOwned

Owned acquire operation Future

OwnedRankedSemaphorePermit

Semaphore permit (owned version)

PriorityConfig

Configuration for priority-based queue strategies.

RankedSemaphore

High-performance priority semaphore

RankedSemaphorePermit

Semaphore permit (borrowed version)

Enums

QueueStrategy

Queue strategy for waiters at a given priority level.

TryAcquireError

Error returned from try_acquire operations.