This feature limits simultaneous web seed requests to prevent the overload of servers when downloading many different items from the same source.  Some servers will throttle remote addresses that are the source of too many requests.  This feature was designed to prevent that.

The limiter configuration can be found in Settings > Transfers > Peers.  There is a button near the bottom to edit the configuration of the limits.



The syntax is fairly simple.

There is one rule per line.  Each line describes a group of hosts that will be collectively limited, followed by an equal sign, and then one or more limit parameters, separated by commas, that control connections to matching hosts.

Host Matching

Each line starts with one or more host names.  Multiple names can be separated by a space.  A host is matched if it ends with any of the host names in the rule, so the host www.mydomain.example would match a rule that specifies mydomain.example.

Host names can also have a wild-card asterisk * for one or more (or all) segments.  This will create a new group of collectively limited hosts for each unique match.  If there was a rule that specified *.mydomain.example, then each different subdomain of mydomain.example would be limited in a separate group.  Connections to server1.mydomain.example would be limited separately from connections to server2.mydomain.example.

The default rule's *.* match will cause connections to each unique combination of the last two segments of a host name to be throttled as separate groups

Limit Parameters

The parameters are everything to the right of the equal sign.

Consider this example:

hostname.example = 8 concurrent, 5 every 30, 8 every 60, 50 kbps

The first part will allow no more than 8 simultaneous connections.  Then connection initiations are rate-limited to 5 every 30 seconds, or 8 every 60.  The last part limits any single connection to 50 kbps.