Module resilience 

Resilience utilities: retry logic, backoff, rate limiting, bulkheads.

This module provides patterns to protect services from overload:

• RetryConfig: Exponential backoff for transient failures
• RateLimiter: Token bucket to prevent thundering herd
• Bulkhead: Semaphore to limit concurrent operations

Example

use replication_engine::resilience::{RateLimiter, Bulkhead, RateLimitConfig};

// Rate limit: max 1000 events/sec with burst of 100
let limiter = RateLimiter::new(RateLimitConfig::default());
limiter.acquire().await; // Blocks if over limit

// Bulkhead: max 10 concurrent connections
let bulkhead = Bulkhead::new(10);
let _permit = bulkhead.acquire().await?;
// permit dropped = slot released

Structs

Bulkhead

Bulkhead pattern: limits concurrent operations to prevent resource exhaustion.

BulkheadFull

Error when bulkhead is full.

RateLimitConfig

Configuration for rate limiting.

RateLimiter

Token bucket rate limiter.

RetryConfig

Configuration for connection retry behavior.