mod_ratelimit
Bandwidth Rate Limiting for Clients
Extension
mod_ratelimit.c
ratelimit_module
rate-initial-burst
available in httpd 2.4.24 and later. Rate limiting proxied content does not work correctly up to httpd 2.4.33.

Provides a filter named `RATE_LIMIT` to limit client bandwidth. The throttling is applied to each HTTP response while it is transferred to the client, and not aggregated at IP/client level. The connection speed to be simulated is specified, in KiB/s, using the environment variable `rate-limit`.

Optionally, an initial amount of burst data, in KiB, may be configured to be passed at full speed before throttling to the specified rate limit. This value is optional, and is set using the environment variable `rate-initial-burst`.

# Example Configuration

<Location "/downloads"> SetOutputFilter RATE_LIMIT SetEnv rate-limit 400 SetEnv rate-initial-burst 512 </Location>

If the value specified for `rate-limit` causes integer overflow, the rate-limited will be disabled. If the value specified for `rate-limit-burst` causes integer overflow, the burst will be disabled.