[tor-relays] running relay severely degrades network performance eventually

[k e bera]

On Mon, 21 Jan 2013 16:31:01 -0700
Nicolas Bock <nicolasbock at gmail.com> wrote:

> every time I run a relay on a Comcast cable connection, after a while (a
> few hours to days) other network operations such as DNS lookups slow down
> to such an extent that the network becomes unusable. Unfortunately I don't
> know how to exactly pinpoint what the problem is, but found that the only
> reliable solution at such a point seems to be to reset the cable modem.
> 
> Is that a known issue? Could you suggest how I can diagnose this more
> accurately?

The dd-wrt page has some hints that may apply if you have a router between your relay and Comcast cable.  Specifically settings such as TCP timeout and Max Connections.  I don't know if Tor already checks those limits and throttles itself to match, or what the recommended router settings are for Tor relays.

http://www.dd-wrt.ca/wiki/index.php/Router_Slowdown