Application of Nginx four-layer load balancing in flash sale system

Application of Nginx four-layer load balancing in flash sale system

Ideas for answering interview questions

Interview question: Why did you choose Nginx’s four-layer load balancing in your flash sale system? Please explain in detail the reasoning behind this choice.

Answer ideas:

1. Introduction: When answering this question, we will first introduce the special characteristics of the flash sale system, that is, the requirements for high concurrency and low latency, and then clarify why we chose four-layer load balancing .

2. Flash sale system requirements analysis:

   • High concurrency: A large number of users flood into the system at the beginning of the flash sale event, and requests need to be distributed quickly and efficiently.
   • Low latency: Users expect flash sale operations to be completed within seconds and are extremely sensitive to delays.

3. Advantages of four-layer load balancing:

   • Fast distribution: Layer 4 load balancing distributes based on IP address and port. The operation is simple and efficient, and it can quickly forward requests to the back-end server.
   • Superior performance: Since it does not involve in-depth analysis of the HTTP protocol, the response is faster and suitable for high concurrency scenarios.

my design

When designing a flash sale system, the choice of load balancing is crucial. The particularity of flash sale activities requires the system to be able to cope with the influx of a large number of users in a short period of time, while ensuring that users can complete the flash sale operation within seconds, which places extremely high requirements on the performance of the system.

Flash kill system requirements analysis

The two main features of the flash sale system are high concurrency and low latency.

• High concurrency: At the beginning of the flash sale activity, thousands of users may access the system at the same time, requiring the system to distribute requests quickly and effectively to ensure that each user has Opportunity to participate in flash sales.

• Low latency: Flash sales are usually very short-lived, and users expect to complete the flash sale operation in a very short time. Any delay may lead to user churn, so it is extremely sensitive to delays.

Advantages of four-layer load balancing

In order to meet the needs of the flash sale system, we chose Nginx’s four-layer load balancing.

• Fast distribution: Four-layer load balancing mainly distributes requests based on IP addresses and ports. Compared with seven-layer load balancing, its operation is simpler and the distribution is more efficient. In the case of high concurrency, this simple and direct distribution method can quickly forward requests to the back-end server, ensuring that users can participate in flash sale activities in a timely manner.

• Superior performance: Because the four-layer load balancing does not involve in-depth analysis of the HTTP protocol, the response is faster than the seven-layer load balancing. This enables the system to maintain a higher performance level in high-concurrency scenarios.