Единственное, что я нашёл: вот. Пример вывода:
$ ./web100clt-XTR-i686-linux -l speedtest.calpop.com
Testing network path for configuration and performance problems
Checking for Middleboxes . . . . . . . . . . . . . . . . . . Done
running 10s outbound test (client to server) . . . . . 1.94 Mb/s
running 10s inbound test (server to client) . . . . . . 522.25 kb/s
The slowest link in the end-to-end path is a 10 Mbps Ethernet subnet
Information: Other network traffic is congesting the link
Information: The receive buffer should be 445 Kbytes to maximize throughput
