Re: TOR slowing down other network services

[Csaba Kiraly <kiraly@xxxxxxxxxxxx>]

Some more info about your link would help in the diagnosis.
If you are on ADSL, as I suppose you are, and available bandwidth is
quite asymmetric, you need most of your uplink BW to send the TCP
acknowledgements for the 4mbps downlink traffic. If your download also
needs data upload, e.g. for some tit-for-tat mechanism, some of your
upload bw should also be dedicated for that, otherwise download slows down.

Now, if you throw Tor traffic in the mix, which tends to be symmetric,
you don't feel it directly on the downlink, but it takes away uplink
resources, which indirectly (through ACK dropping and through
tit-for-tat) hits back, reducing your effective downlink speed.

You can try defining your priorities .... we had a thread on that
somewhere ... see
http://archives.seul.org/or/talk/Feb-2008/msg00047.html
http://archives.seul.org/or/talk/Sep-2007/msg00419.html

Csaba


Rochester TOR Admin wrote:
> I am running a tor exit node and have been doing some testing on
> bandwidth consumption.  The tor server is running linux and is also
> used for TorrentFlux - a web based torrent management application. 
>
> The issue I'm noticing is while I'm downloading a torrent that is
> coming in at about 1mb/s and I stop the tor service, the torrent
> downloads at 4mb/s.  The tor service is correctly using 40kbps of my
> bandwidth but it seems to be limiting the bandwidth of other
> services.  Is this possible?
>
> A few other environment factors:
>  - my firwall is a pretty old machine with a very slow NIC
>  - my tor server NIC is very cheap [<$10]
>
> Could anyone give me some insight about what they think might be going on?
>
> Thanks in advance...
>
> Rochester TOR Admin
> running server torroc01