$limit_rate

Description

The `$limit_rate` variable in NGINX is used to limit the transfer speed for responses sent to clients. By adjusting this variable, administrators can ensure a maximum bandwidth consumption from a specific connection, which can be particularly useful in scenarios where managing server resources becomes crucial, such as during high traffic periods. The variable can be set to a specific byte value or it can derive its value from other variables, allowing flexible configurations depending on the needs of the application. This variable can be set dynamically, depending on various conditions within the configuration, such as IP addresses or specific request characteristics. The default state has `$limit_rate` set to zero, meaning there is no limit on the transfer speed. If set value is greater than zero, NGINX will apply the limitation per request and adjust the speed accordingly, which might significantly impact user experience if the rate is set too low. Commonly, values are given in bytes per second; for example, setting it to `1048576` would restrict the rate to `1MB/s`.

Config Example

http {
    server {
        location / {
            # Limit transfer rate
            limit_rate 500k;
        }
    }
}