Accepted
Our microservices architecture needs to handle failures gracefully and provide reliable message processing. We need to implement patterns that ensure system resilience and prevent cascading failures.
We will implement the following resilience patterns using Resilience4j:
- Circuit Breaker: Prevents cascading failures by temporarily stopping calls to failing services
- Retry: Automatically retries failed operations with exponential backoff
- Bulkhead: Isolates failures by limiting concurrent calls
- Rate Limiting: Prevents overwhelming downstream services
- Manual Acknowledgment: Selective acknowledgment of successfully processed messages
- Dead Letter Queue: Handles messages that fail processing after retries
- Fault Tolerance: System continues operating despite component failures
- Graceful Degradation: System degrades gracefully under load
- Recovery: Automatic recovery from transient failures
- Monitoring: Clear visibility into failure patterns and recovery
- Isolation: Failures are contained and don't cascade
- Reliability: Improved overall system reliability
- Complexity: Additional complexity in error handling
- Latency: Retry mechanisms add latency to failed operations
- Resource Usage: Circuit breakers and bulkheads consume resources
- Configuration: Complex configuration for optimal behavior
- Testing: More complex testing scenarios required
- Trade-offs: Balance between reliability and performance
- Monitoring: Requires monitoring of resilience patterns
- Documentation: Need to document failure scenarios and recovery
- Custom Implementation: Rejected due to maintenance overhead
- Hystrix: Rejected due to being in maintenance mode
- No Resilience Patterns: Rejected due to poor reliability
- Simple Retry: Rejected due to insufficient fault tolerance
- Circuit breaker configured with sliding window and failure rate threshold
- Retry with exponential backoff and maximum attempts
- Bulkhead limits concurrent SQS message processing
- Manual acknowledgment allows partial batch success
- Dead letter queue handles permanently failed messages
- Metrics and monitoring for all resilience patterns