Apache HTTP Server, commonly known as Apache, is an open-source web server software developed by the Apache Software Foundation. It is widely used for hosting websites and applications due to its flexibility, security features, and modular architecture. Apache supports various functionalities such as virtual hosting, URL rewriting, SSL/TLS encryption, and reverse proxy capabilities. It is compatible with multiple operating systems, including Linux and Windows, and can be configured using its extensive set of modules to optimize performance and security for different use cases.
Earlier, Apache HTTP Server followed a process-per-request model, where each incoming request spawned a new process to handle it. While this approach ensured isolation and stability, it was inefficient because process creation consumed significant memory and CPU resources. For high-traffic servers, this led to excessive overhead and poor scalability.
To improve efficiency, Apache introduced thread-based handling in its worker (multi-threaded) and event-driven MPMs (Multi-Processing Modules). Instead of creating a separate process for each request, Apache now uses threads within a process, reducing memory usage and context-switching overhead. This allows it to handle thousands of concurrent connections more efficiently, making it a better fit for modern web applications.
A database server is a system that provides database services to clients by managing and storing data efficiently. It handles requests from applications to retrieve, update, or delete data using query languages like SQL. Database servers ensure data integrity, security, and performance optimization through indexing, caching, and transaction management. Popular database servers include MySQL, PostgreSQL, Microsoft SQL Server, and MongoDB. They can be relational (RDBMS) or non-relational (NoSQL), depending on the data structure and requirements. Database servers play a crucial role in modern applications by enabling scalable and reliable data storage solutions.
Nginx is a high-performance, open-source web server and reverse proxy that efficiently handles multiple concurrent connections using an event-driven architecture. Unlike traditional web servers that rely on a process-per-request or thread-per-request model, Nginx uses a non-blocking, asynchronous approach where a single worker process can handle thousands of connections simultaneously.
Nginx achieves this by using an event loop that listens for incoming requests and processes them using callbacks, reducing CPU and memory usage. This design makes it highly scalable, making it a preferred choice for serving static content, load balancing, reverse proxying, and handling high-traffic websites efficiently.