The High-Performance Series

How to design a system to scale to your first 100 million users

Think Big, Do Small, Learn Fast

In order to keep up with emerging techniques, I would like to update you on this story throughout the year.
Last updated on 2021 Dec 23

Photo by Kirill Sh on Unsplash

It is not easy to design a system that supports hundreds of millions of users. It always is a big challenge for a software architect (but it’ll be easy from today after reading my article 🤣)

Here are some topics covered by me in this article.

• Start with simplest: all in one.
• The art of scalability: scaling out, scaling up.
• Scaling a relational database: master-slave replication, master-master replication, federation, sharding, denormalization, and SQL tuning.
• Which database to use: NoSQL or SQL?
• Advanced concepts: caching, CDN, geoDNS., etc.

Today I don’t want to discuss general terms in high-performance computing such as fault tolerance, reliability, high availability., etc.

Keep calm, let’s start now!

Start from scratch

In the figure below, I would like to start by designing a basic app with some users. The simplest way is to deploy the entire app on a single server. This is probably how most of us get started.

• A website (include APIs) is running on a webserver like Apache¹ (or Tomcat²).
• A database like Oracle³ (or MySQL⁴).

We have both the webserver and the database server on the same physical machine

But there are the following disadvantages with the current architecture.

• If the database fails, the system fails.
• If the webserver fails, the entire system fails.

In this case, we don’t have failover and redundancy. If a server goes down, all goes down.

Using a DNS server to resolve hostnames and IP addresses