Why Open file cache in Nginx? - Purpose & Use Cases

The Big Idea

What if your server could serve files instantly without the repeated hassle of opening them every time?

The Scenario

Imagine a busy website server that must open the same files over and over for every visitor, like repeatedly fetching the same menu from a restaurant kitchen for each customer.

The Problem

Opening files every time wastes time and server power, causing slow responses and making visitors wait longer. It's like the kitchen staff having to find and prepare the menu fresh for each customer instead of just handing it over.

The Solution

Open file cache keeps the files ready and waiting in memory, so the server can quickly serve them without reopening. This is like having menus already printed and ready on the counter, speeding up service and reducing effort.

Before vs After

✗ Before

open file for each request
read file
close file

✓ After

use open_file_cache to keep files open
serve from cache
reuse open files

What It Enables

It enables faster website responses and reduces server load by reusing open files efficiently.

Real Life Example

A news website serving thousands of visitors can deliver articles faster by caching open files, avoiding delays caused by repeatedly opening the same article files.

Key Takeaways

Opening files repeatedly slows down servers.

Open file cache keeps files ready in memory.

This speeds up responses and saves server resources.