HashiConf The full conference agenda's now LIVE. Buy your pass and plan your schedule. Register
Well-Architected Framework
Well-Architected Framework Home

Scale and tune performance

Scaling and performance tuning are critical aspects of fault-tolerant systems, with complex relationships that can be complementary or conflicting. Understanding these relationships helps you design systems that achieve both high availability and optimal performance.

The same redundant components that enable fault tolerance can also support load balancing to improve performance. Geographically distributed replicas for disaster recovery can also reduce latency for users in different regions. Excess production capacity needed for fault tolerance can provide additional performance headroom during peak loads.

However, there are trade-offs to consider. Stronger consistency guarantees for fault tolerance often require extra network round trips that impact performance. Synchronous replication for durability can affect latency, and complex recovery mechanisms can slow down regular operations. Resource overhead for redundancy increases costs, while health checking and monitoring consume processing power and bandwidth.

Implement bulkheads and circuit breakers

Use bulkheads and circuit breakers to isolate components so that failures do not cascade across your entire system. These patterns help you maintain system stability and prevent single component failures from bringing down your entire application.

Implement back-pressure mechanisms to prevent overload when components cannot keep up with incoming requests. These mechanisms help your system gracefully handle traffic spikes and prevent resource exhaustion that could lead to cascading failures.

Design for graceful degradation by ensuring that your system can continue operating with reduced functionality when certain components are unavailable. This approach maintains user experience even during partial failures and allows your system to recover automatically when components become healthy again.

Configure your HashiCorp tools to take advantage of their built-in fault tolerance features. Consul's service mesh provides automatic circuit breaking and load balancing, while Nomad's autopilot features help maintain cluster health and performance.

Optimize caching and state management

Improve resilience and performance by implementing local state management to reduce network dependencies. Local caching reduces the need for frequent network calls and provides faster response times for frequently accessed data.

Implement cache hierarchies that offer fallback options when primary data sources are unavailable. This approach ensures that your application can continue serving requests even when backend services are experiencing issues.

Use distributed caching solutions that can handle failures gracefully while maintaining performance. These solutions provide redundancy and ensure that cache failures do not impact application availability.

Configure your applications to use appropriate caching strategies based on data characteristics and access patterns. Consider factors like data freshness requirements, memory constraints, and network latency when designing your caching strategy.

Monitor and adapt to system conditions

Implement comprehensive monitoring to catch potential failures before they impact your system. Use metrics and logs to identify performance bottlenecks, resource constraints, and early warning signs of system degradation.

Configure automatic scaling and recovery systems that respond to overload and failure conditions. These systems should automatically adjust resource allocation, restart failed components, and route traffic away from problematic instances.

Design your capacity planning to account for both regular operation and operation in different failure modes. Ensure that you have sufficient resources to handle normal load plus the additional overhead of running in degraded mode during failures.

Use HashiCorp's monitoring capabilities to track system health and performance. Consul provides service health checking and metrics collection, while Nomad offers cluster monitoring and autoscaling features that help maintain optimal performance.

Test and validate system behavior

Conduct load testing to understand how your system performs under various conditions and identify performance bottlenecks. These tests help you validate that your system can handle expected load levels and identify areas for optimization.

Include testing of failure scenarios in your validation process to ensure that your fault tolerance mechanisms work correctly. Test how your system behaves when components fail, networks partition, or resources become constrained.

Use chaos engineering principles to help understand system behavior at scale and under stress. Chaos engineering involves intentionally introducing failures to validate that your system can handle them gracefully and recover automatically.

Include recovery scenarios in your performance benchmarks to ensure that your system can recover quickly from failures without significant performance degradation. These benchmarks help you validate that your fault tolerance mechanisms do not unduly impact normal operation.

Next steps

In this section of Design resilient systems, you learned about scaling and tuning performance in fault-tolerant systems, including implementing bulkheads and circuit breakers, optimizing caching and state management, monitoring and adapting to system conditions, and testing and validating system behavior. Scale and tune performance is part of the Design resilient systems pillar.

Refer to the following documents to learn more about designing resilient systems:

If you are interested in learning more about scaling and performance tuning, you can check out the following resources:

Edit this page on GitHub