Varnish cache is an accelerator software for web applications that you install in front of an HTTP web server to cache the server output and reduce the application, website, or API loading time. It is also called a reverse proxy and is configured to cache the website contents. It is swift and can speed up delivery by as much as 300-1000x depending on the architecture.
Two of the most significant characteristics of Varnish cache are performance and flexibility.
- Performance: Varnish is a high performer. Most of the time, it is bound by the network speed, which means it doesn’t have any issue of its own. Varnish is capable of delivering more than 20GBbps regularly on off-the-shelf hardware.
- Flexibility: Besides its performance, a significant feature of the Varnish cache is its flexibility in the configuration language (VCL). This language allows you to write your policies on the way to handle incoming requests. This policy will enable you to decide the content you would serve, where you’re getting the content, and how the response or request is altered.
