#summary Connection-level rate limiting
#labels Stage-Beta

= Introduction =

On some servers, especially public ones, it is desired to make sure that everyone gets their fair share of system resources (and no more).

mod_limits allows you to specify traffic bandwidth limits, preventing any single connection hogging the server's CPU, RAM and bandwidth.

= Details =

mod_limits detects when a connection has exceeded its traffic allowance and temporarily ignores a connection. Due to the way TCP and the OS's network API works no data is lost, only slowed.

= Configuration =
Currently mod_limits is configured per connection type. The possible connection types are:

  * c2s
  * s2sin
  * s2sout
  * component

The limits are specified like so:

{{{
    limits = {
        c2s = {
            rate = "3kb/s";
            burst = "2s";
        };
        s2sin = {
            rate = "10kb/s";
            burst = "5s";
        };
     }
}}}

All units are in terms of _bytes_, not _bits_, so that "kb/s" is interpreted as "kilobytes per second", where a kilobyte is 1000 bytes.

= Compatibility =
| 0.9 | Works |
| 0.8 | Doesn't work(*) |

(*) This module can be made to work in 0.8 if you do two things:
  # Install [http://hg.prosody.im/0.9/raw-file/d46948d3018a/util/throttle.lua util.throttle] into your Prosody source's util/ directory.
  # If you use libevent apply [http://prosody.im/patches/prosody08-mod-limits-fix.patch this patch] to net/server_event.lua.