Bulletproofing for Black Friday video recap
Black Friday sales aren’t just a one-day scramble—they’re the ultimate test of your application’s readiness. By replicating peak scenarios in a controlled ‘blank Black Friday,’ you can uncover hidden bottlenecks long before real customers show up.
By Thomas di Luccio, on Jan 22, 2025 Every year, Black Friday is the ultimate stress test for e-commerce sites. Scalability, performance, and resiliency come into the spotlight as traffic spikes. At SymfonyCon Vienna 2024, I had the opportunity to share my experience, tips, and best practices on how to keep your application from buckling under peak loads.
Black Friday is that one moment in the year when all the optimizations—or lack thereof—surface dramatically. Teams often scramble at the last minute to ensure their application can handle the load.
Continuous Observability is not just about monitoring your application in production; it’s about detecting and diagnosing performance issues early, ideally in development and staging.
During my talk, I reflected on a personal experience of a failed product launch, during which all applications crashed under the load. Among the many reasons behind this failure lies a total lack of preparation. We were unable or unwilling to test our solution for such traffic preemptively.
Regaining control over peak-traffic events
A key strategy to master high-traffic events such as Black Friday or significant product launches is the ability to simulate them on demand in controlled environments. This approach—think of it as running a “blank Black Friday”—lets you proactively pinpoint and address potential bottlenecks before they affect your actual customers. Here’s how you can do it:
- Generate realistic traffic
Use load-testing tools alongside data extracted from your application’s APIs to simulate authentic user behavior. This ensures that the traffic patterns you’re generating are not just heavy in volume, but also accurately mimic the complexity of real production usage. - Clone your production environment
Employing production data cloning tools (like what Upsun provides) allows you to work with carbon copies of your production setup. By replicating the exact configuration and data, you’ll spot the same issues that could plague your live system, allowing you to fix them early. - Integrate observability
Bake observability into your development and deployment workflows using solutions like Blackfire. This provides end-to-end visibility into how your application and infrastructure perform under stress. You’ll gain a deeper understanding of resource usage, throughput, and potential choke points—before they surface in production. - Adopt fine-grained resource allocation
Finally, assign the right resources to each container or service, optimizing for performance and efficiency. You keep costs and carbon emissions in check by continuously monitoring and adjusting these allocations, even as you scale up to meet demand.
By simulating peak events in controlled, observability-driven environments, you can regain control over your application’s performance and ensure a smooth, cost-effective user experience—even during the busiest times.
Performance matters, from the chaos of Black Friday to the day-to-day operations that power your application. By embracing Continuous Observability and weaving profiling into every step of your development and deployment, you’ll bulletproof your application and deliver seamless experiences to your users—even on the busiest days of the year.
Watch the full recording of the “Bullet proofing for Black Friday” talk.
To better observability and beyond
