Hi All,
Ive recently installed a 700Mb Ubiquiti AF24 link between two CCR routers.
I can push 500Mb RX and TX on UDP between the two, however with TPC I can only push around 110Mb (20-50 TCP Streams)
Does anyone have any insight as to why?
Latency. Tcp waits for confirmation and that makes delays. Udp just pushes packets not looking around.
Or singlethread processing of btest. See the cpu usage…
Latency is sub 10ms.
And im pushing 20 TCP streams at CPU is at 12% so its not that.
Does anyone else have any ideas?
Jarda already guessed that in his first answer…
10ms is huge latency for TCP! Just try to imagine it - UDP is sending packets as fast as possible - utilizes maximum of bandwidth. TCP sends a paket (only one per stream!) and then waits for response. As you said - latency is around (or slightly below) 10ms, so there is approximate delay 10ms after every packet (per stream).
This kind of difference is perfectly normal and expected as a result of waiting for confirmation packet from recipient.