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Nginx – The High Performance Web Server Powering Millions of Websites

Published on January 28, 2022
Nginx – The High Performance Web Server Powering Millions of Websites

If you've ever used the Internet, you've definitely used an Nginx server. Nginx (pronounced "engine-x") is an open-source web server application that powers over 422 million websites worldwide. While the platform was created in 2002 when Igor Sysoev first began the project, it didn't get its name Nginx until 2004 - before that, it was known as "Lighttpd". Initially, it was created to solve the C10k problem, which is the challenge of handling ten thousand connections on a single server. Now, it is the most popular open-source web server application, and it powers some of the most significant websites on the Internet, including Netflix, Hulu, Pinterest, Airbnb, and GitHub.

What is Nginx?

Nginx is an open-source HTTP server but is also used as a reverse proxy, load balancer, and web cache built for high performance. The server can process up to 400,000-500,000 requests per second (RPS). Nginx scales by clustering multiple servers together and has built-in load balancing and failover mechanisms. Because of its event-driven architecture, Nginx is highly efficient and uses a small number of system resources. Nginx scales in all directions: from the smallest VPS to an enterprise infrastructure, Nginx serves at scale with stability and speed.

A single Nginx instance can replace Apache as well as any other type of software commonly used to serve content, implement load balancing or caching, etc. Nginx serves static files very efficiently by using lightweight HTTP 1.1 keepalive, allowing many concurrent file downloads from a single connection. An increasingly common use for Nginx is as a reverse proxy. Nginx is very easily configurable, and there are many supporting modules documented on the Nginx website. It can provide security by implementing SSL encryption, caching, load-balancing, and full web development. Nginx is similar to Apache's mod_rewrite module, which translates URLs into different URLs to handle any type of request.

Nginx reverse proxies are very flexible because they can work on many different ports or even just pass requests onto another service or HTTP server that is configured to handle the request.

Some of Nginx's main features

  • Multi-core support (up to 1024 CPUs)
  • HTTP & TCP/UDP Load Balancing
  • Web caching
  • Media streaming/serving
  • HTTP compression
  • FastCGI caching
  • Static content serving
  • URL rewriting, redirecting & authenticating
  • A/B testing

Primary use case

Nginx is designed to be a high-performance web server. It uses an asynchronous, non-blocking approach to handling requests. This makes the platform extremely fast and easy to scale horizontally in a distributed environment.

Nginx can also be combined with PHP or Python application servers. Nginx powers a massive proportion of the world's busiest websites due to its ability to handle high amounts of traffic at one time. It can also be used in front of another application server as a reverse proxy to load balance requests, or it can function as a full-fledged web server by itself due to the fact that Nginx has its own address and port. Nginx can also be used to serve static content, cache requests, or enable SSL & HTTP/2 support. Nginx scales by clustering multiple Nginx hosts together for extra performance and redundancy. Nginx is also very lightweight (typically using less than 100 MB of RAM)

Advantages of using Nginx

A large volume of connections

One of the platform's biggest strengths is its ability to handle large numbers of connections. Nginx can handle tens of thousands of concurrent connections without breaking a sweat. The Nginx worker process architecture is optimized to take full advantage of all available CPUs to handle even the most demanding workloads. For example, Netflix needs to serve millions of concurrent subscribers at once, so they turned to the unlimited extensibility of open-source software.

Memory efficiency

Nginx is very efficient in memory usage, which is critical when you are dealing with tens of thousands of concurrent connections. It is very lightweight (typically using less than 100 MB of RAM). It is able to achieve this without sacrificing performance because Nginx processes run as a single process with multiple threads, which makes the system much more efficient than some other methodologies, such as Apache's prefork design.

Asynchronous processing

The Nginx event model uses asynchronous processing whenever possible and requires only a single multi-process Nginx core to handle thousands of simultaneous connections. Nginx will continue to work as long as at least one worker process is still running, even if the master process fails for some reason.

Resource efficiency

Nginx is efficient when it comes to resource usage, allowing for speedy responses in comparison with traditional servers like Apache HTTP. It also has built-in load balancing capabilities, which enable you to use Nginx as a reverse proxy in front of your cluster of application servers, effectively giving each request its own dedicated CPU core. Simply put, Nginx makes applying changes easy and gives you access to detailed performance metrics that can help optimize your web services.

Search engine optimization

Because Nginx makes your website faster, search engines correctly prioritize your site over slower sites that load on web servers. Nginx is an optimal way to work with SEO best practices by speeding up the website and making it more relevant for users.


Nginx can run on all major operating systems, including Linux, macOS, BSD variants, Solaris, and Windows (experimental support). The company has also developed an elevated version of Nginx called "Nginx Plus", which they describe as being "the world's first commercial-grade, fully-featured and enterprise-ready" Nginx. Nginx Plus includes a load balancer, content cache, and web server to which Nginx users can upgrade by paying for commercial Nginx Plus licenses. It is also compatible with many of the most common web applications, including Joomla, Python, Ruby, etc.

Nginx vs Apache

It really depends on what you need when it comes to comparing the two. While Apache has always reigned supreme (and still may, depending on who you ask), Nginx has amassed a bigger market share in recent years. This is due to its high performance, low latency, and memory efficiency – all without sacrificing the support for the rich set of features that Nginx users know and love.

Nginx can serve static content (like images) much more efficiently than Apache because it can cache it right on Nginx's end without needing to go back to disk. Nginx can also handle more concurrent requests, making it ideal for bandwidth-intensive sites.

While Nginx has some features that Apache does not have (e.g., load balancing), Nginx lacks some core features that Apache has, such as .htaccess. Nginx is also not designed for distributed sites and doesn't support load-balancing with cookies, so if you have a site that requires user authentication at the beginning of each session, Nginx isn't an option.

When to consider using Nginx

The websites that best benefit from using Nginx is its low latency. It is primarily websites that need to serve many users simultaneously. Nginx is meant for large numbers of concurrent connections and is the best solution if you anticipate:

  • High traffic
  • Static or cacheable content (e.g., images, CSS)
  • Website environments with specific requirements such as session sharing

Nginx is also suitable for sites that are doing a lot of content delivery, like streaming media, because it makes the process of updating the website faster and more efficient. It is designed to support high disk I/O operations, which makes it optimal for serving static content rather than dynamic web pages. Because it does not support server-side scripting, it is good for serving pre-rendered content from a cache but not dynamic content.

When to use Apache instead

Apache is most effective when serving dynamically-generated content because Nginx does not support server-side scripting. Nginx can do some limited dynamic processing using its Nginx Lua module, but the two are not designed to work together efficiently. Nginx is often used in front of Apache to offload static content so it can be served more quickly and efficiently. Still, Nginx works best as a reverse proxy to serve content from a cache rather than dynamically generating it. Apache also boasts better OS support. It supports all Unix-like systems (like Linux and BSD) and fully supports MS Windows. This makes it a more viable option for some.

Another key difference is that Apache offers additional configuration via .htaccess files. This means that non-privileged users can make edits to certain parts of a site without having full configuration access (like Nginx requires). Nginx doesn't support .htaccess files.


To conclude, Nginx works best when serving static content, handling large amounts of concurrent users, and as a load balancer for other Nginx servers. It is designed to support high disk I/O operations and does not support server-side scripting – Apache gives users more flexibility and can handle more complex setups.

It has grown in popularity due to its scalability and performance in high-traffic situations. Therefore, it is also a good choice if you anticipate a high volume of users. If, however, your website requires dynamic content, then Nginx will not be as useful. Apache is better suited as a general-purpose webserver, and Nginx can be used to proxy requests from it to speed up static content delivery.

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