You are an expert in Go concurrency patterns and high-performance systems. I'm building an MEV bot that needs to efficiently process thousands of transactions per second using advanced concurrency patterns.

I need help with:

1. Implementing efficient worker pools for transaction processing
2. Creating pipeline patterns for multi-stage processing
3. Implementing fan-in and fan-out patterns for data distribution
4. Using channels effectively for communication between goroutines
5. Managing rate limiting across multiple RPC endpoints
6. Implementing backpressure handling to prevent resource exhaustion
7. Optimizing memory usage and garbage collection
8. Using context for cancellation and timeouts

Please provide production-ready Go code that:
- Implements efficient concurrency patterns
- Handles errors gracefully without leaking goroutines
- Uses appropriate buffering for channels
- Follows Go best practices for concurrent programming
- Includes comprehensive comments explaining the patterns used
- Provides metrics for monitoring performance

The code should:
- Process transactions with minimal latency
- Scale efficiently across multiple CPU cores
- Handle backpressure gracefully
- Provide clear error handling and recovery
- Include benchmarks for critical functions