[tor-relays] Fwd: Throughput of each circuit

[Matt Traudt]

On 12/4/18 4:48 PM, marziyeh latifi wrote:
> 
> Hello,I have two questions about tor's relay:
> 1-How can I calculate the throughput of each circuit in a relay?I mean
> that how can I calculate the number of cells that are sent from circuit
> queue to the output buffer per second in each relay?

You might be able to with the CIRC_BW control command.
https://gitweb.torproject.org/torspec.git/tree/control-spec.txt#n2988
(I'm not sure if this is a client-only command or if relays can use it
for circuits that go through them)

If not, I don't think you can without modifying Tor's source code.

> 2-What is the difference between circuit and channel in relays?
> I'm looking forward to hearing from you!
> thanks!

Channels are a thin wrapper around connections (which themselves are a
nice wrapper around TCP sockets) in Tor's source code.

There can be many circuits on a channel.

Matt

PS: this question makes more sense for tor-dev@