I'm a rookie Tor relay operator but would like to give back to the community. According to the data in the arm-software (https://www.torproject.org/projects/arm.html.en) my Tor settings - the torrc-file - seems to be ignored.

I've added the following settings to the top of my file (update 05-aug-2014: please see image at bottom for current torrc):

Nickname myNick
ContactInfo myMail
ORPort 443
DirPort 80
ExitPolicy reject *:*
Log notice file /var/log/tor/notices.log

RelayBandwidthRate 500 KB
RelayBandwidthBurst 2 MB

ControlPort 6051
CookieAuthentication 1

Notice the bandwidth rate set to 500 kb/s (I suppose).

From the arm tool, however, this is what I see:

Tor Relay Arm Snapshot

Notice the measured speeds. The average speeds are way above the speeds I set in the torrc-file, and sometimes I've seen the burst rate exceed 3 mb/s. It is a requirement that the maximum average speed in kb/s is fixed at 500, and that it's working, else I will eventually run dry of bandwidth from my ISP.

Do you have any idea of what went wrong and how to fix it?

Edit: Another fun observation is the highlighted (grey) text in the screenshot:

Bandwidth (limit: 3.9 Mb/s, burst: 16.0 Mb/s, measured: 3.0 Kb/s)

Where does this information come from? I'm not even able to neither download nor upload with 16 Mb/s. I have a measured speed of 111.6/22.5 kbit/s.


According to the logs in the following screenshot, tor only uses a few hundre kb/s of bandwidth, yet the arm tool reports an average bandwidth of 1 mb/s. This 1 mb/s doesn't add up to the total amount of data send/recieved, though!

Here's the image:

Updated screenshot showing strange differences in average speeds

As per request, here is the torrc as seen from within arm (Note: KBytes and MBytes are used in actual file):

torrc as seen from within arm

Here is a quick look at the current speeds:

Current speeds

When I left it like that it continued to up- and download with 2 mb/s (it is allowed to burst like that) - the top of the graph shown in this image peaked at about 4.5 mb/s. The average speed is still 3 times higher than permitted, however. Maybe the aim of the average speed is per week or even per month based?

  • Could you go to page 3 (two times right button) and check how arm parsed the config file? – Jens Kubieziel Aug 5 '14 at 14:54
  • @JensKubieziel: Please have a look at the updated post. :) – Izmaki Aug 5 '14 at 15:50

You set values for RelayBandwidthRate and RelayBandwidthBurst in your torrc. RelayBandwidthRate is set to 500 KB. This translates to 500 kilo Bytes per second, which is 500*8=4000 Kilo Bits per second. arm somehow rounds this number down to 3.9 Mb/s. On your screenshot that shows the torrc inside arm you changed the number to 250 KB and arm shows 2 Mb/s.

The RelayBandwidthBurst is similar. You set a value of 2 Mega Bytes and arm translated it to 16 Mega Bits.

The up- and download numbers are also shown as Megabits per second. Your relay has roughly 1 Mb/s which is below 2 Mb/s.

So if you change the RelayBandwidthRate to 500 KBits you'll see a drop in traffic and I assume also arm will show the correct numbers to you.

  • It says on the man-page for RelayBandwidthRate that "Relayed traffic currently is calculated to include answers to directory requests, but that may change in future versions. (Default: 0)". Do you know if this has changed since the man-page was written? I will try to set the other parameter, see what happens and report back when I wake up or get back from work. – Izmaki Aug 4 '14 at 22:55
  • OK, so, 16 hours later the current speeds and torrc as arm reads it can be seen in the updated question. The avg speeds are still 3 times higher than permitted, but at least the burst rate seems to behave somewhat nicely (not shown, but observed after snapshot was taken). – Izmaki Aug 5 '14 at 15:52
  • Since I never managed to get my relay fixed, I've decided to shut it down completely for the time being. It didn't solve my question (unless of course I need to wait a month or whatever before I can see the average numbers match up), but it was very useful. ...and thanks for that. :) – Izmaki Aug 13 '14 at 9:30

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