This tracker is open in a sense that everyone announcing a torrent is welcome to do so and will be informed about anyone else announcing the same torrent. Unless -DWANT_IP_FROM_QUERY_STRING is enabled (which is meant for debugging purposes only), only source IPs are accepted. The tracker implements a minimal set of essential features only but was able respond to far more than 10000 requests per second on a Sun Fire 2200 M2 (thats where we found no more clients able to fire more of our testsuite.sh script). Some tweaks you may want to try under FreeBSD: sysctl kern.ipc.somaxconn=1024 sysctl kern.ipc.nmbclusters=32768 sysctl net.inet.tcp.msl=10000 sysctl kern.maxfiles=10240