Comparing Horizontal and Vertical Scaling in Modern Systems

System Design is the Real Software Engineering !

I’ve always been curious about how massive real-world applications like Amazon and Swiggy operate behind the scenes. What makes them handle millions of users at peak times without going down offline !

The answer lies in System Design—the core of software engineering beyond frameworks and libraries. I’ve been diving into how these giants handle scale, and it’s mind-blowing!

Ever wondered how platforms like Amazon handle Black Friday or how Swiggy manages its servers during New Year when everyone’s ordering in ?

The secret lies in System Design — the backbone of scalable software engineering.

🔍 Let me show you some Real world examples :

Amazon : During high-traffic events , Amazon doesn’t just rely on a single server getting beefed up (that’s vertical scaling). Instead, it horizontally scales by adding thousands of extra servers across different regions. They use load balancers to distribute traffic evenly, ensuring fast and seamless service even with millions of users online at once.

Swiggy : Think of the times during festivals when everyone is ordering food simultaneously. Swiggy uses auto-scaling cloud infrastructure (think AWS, Google Cloud) to automatically add more computing resources in real-time as demand spikes. It’s like hiring extra delivery drivers just for that day! 🛵

📊 Auto-Scaling happens in Both Amazon and Swiggy depend on cloud services to dynamically add resources when they hit a predefined limit.

This allows them to scale horizontally, handling more requests without crashing or slowing down.

Horizontal Scaling: increase no. of machines

Vertical Scaling: increase capacity of machine

However, vertical scaling has its limitations. You’ll eventually reach a point where you’ve maxed out the RAM/CPU of the machine and you can’t upgrade it further. At that point, you’ll need to consider splitting the workload up across multiple machines.

The benefit of horizontal scaling is that it’s virtually limitless. Companies like Google and Amazon have used horizontal scaling to handle billions of users concurrently.

💻 System design isn’t just about code and frameworks. It’s the architecture Built by some great software engineers that keeps our favorite apps running smoothly, even when everyone’s online at once.

Scaling is not just about adding more servers - it's all about:

Smart architecture decisions Handling failures gracefully

funfact : During peak hours, these systems process more transactions per second than many banks!

This journey into system design is just getting started, and I’m excited to keep sharing my progress as I uncover more of the magic behind how these real-world applications work.