WhatsApp handles 3 MILLION TCP Connections Per Server! How do they do it? Let us discuss

Summary

In this engaging video, Hussain explores WhatsApp's impressive technical architecture, particularly its handling of TCP connections, reaching up to 3 million connections per server. He emphasizes the importance of simplicity in engineering, contrasting it with the complexities of modern microservices. Hussain speculates on WhatsApp's server processes and load balancing techniques while expressing a desire for more transparency from the WhatsApp engineering team. His insights reveal the critical balance between performance and simplicity, making this discussion relevant for anyone interested in software engineering and communication technology.

Takeaways

• 😀 Hussain is using OBS for the first time and expresses appreciation for the tool's functionality.
• 📱 WhatsApp is primarily used for communication in the Middle East and India, serving as a key messaging application.
• ⚙️ The discussion centers around the technical workings of WhatsApp, particularly its use of TCP connections.
• 🚀 WhatsApp has successfully scaled from one million TCP connections per server in 2011 to three million by 2016.
• 🛠️ Simplicity in architecture is emphasized as a crucial factor for efficient system design and performance.
• ❓ Hussain raises questions about whether WhatsApp operates on a single process or multiple processes to handle connections.
• 🔄 The video contrasts client-side load balancing with server-side load balancing, highlighting the pros and cons of each method.
• 📈 Efficient management of TCP connections contributes to WhatsApp's ability to maintain constant communication with users.
• 💻 Hussain expresses a desire to connect with WhatsApp engineers to clarify technical aspects of their infrastructure.
• 🧩 The conversation reflects on the challenges and complexities of designing scalable communication systems in modern applications.

Q & A

What is the main topic discussed in Hussain's talk?

Hussain discusses the architecture and scalability of WhatsApp, particularly its ability to handle TCP connections and the implications for engineers.

What tool is Hussain using for the first time during his recording?

Hussain is using OBS (Open Broadcaster Software) for the first time to record his session.

How many TCP connections per server did WhatsApp reportedly handle in 2011?

In 2011, WhatsApp was able to handle up to 1 million TCP connections per server.

What does Hussain believe about WhatsApp's communication protocol?

Hussain believes that WhatsApp likely uses raw TCP for its communication protocol, potentially with custom headers for performance optimization.

What significant change did WhatsApp achieve by 2012 regarding TCP connections?

By 2012, WhatsApp increased its capacity to handle up to 2.2 million TCP connections per server.

What engineering principle does Hussain emphasize in his discussion?

Hussain emphasizes the importance of simplicity in engineering design, suggesting that complexity can complicate applications and systems.

What questions does Hussain raise about WhatsApp's server architecture?

Hussain questions whether WhatsApp operates with a single process managing all connections or if multiple processes are used, and how they manage the scaling of connections.

What role do load balancers and reverse proxies play in WhatsApp's architecture according to Hussain?

Hussain discusses the possibility of load balancers and reverse proxies in managing connections between clients and WhatsApp servers, suggesting they help in balancing the load across multiple servers.

What alternative load balancing approach does Hussain mention?

Hussain mentions client-side load balancing, where clients can connect directly to servers based on geographic location, potentially reducing the need for backend load balancers.

What does Hussain wish for regarding WhatsApp's engineering practices?

Hussain expresses a desire for more transparency from WhatsApp regarding their engineering decisions and practices, hoping for discussions that clarify their scalability strategies.