On Sat, Mar 12, 2011 at 04:57:58PM -0500, Flamsmark wrote:
On 2 March 2011 07:37, Karsten Loesing karsten.loesing@gmx.net wrote:
We lost 2 of our 4 bandwidth scanners between Saturday at 18:00 UTC and Tuesday at 14:00 UTC. We need at least 3 scanner results for clients to use the measured bandwidth values instead of the self-reported ones.
Have you considered adding more bandwidth scanners? Is the quorum of 3/4 designed to prevent a pair of scanners from being evil, or to ensure that representative sample is used?
Mike would be a better person to answer this.
My guess is that we should add more bandwidth scanners. The main problem is that the bandwidth scanners are quite resource-intensive in terms of bandwidth (surprise!), RAM, and personal care by the operator. Also, the bandwidth scanner results are tied to a directory authority vote, so the scanner should be run by the directory authority operators themselves or by a person trusted by them.
The requirement of having at least 3 bandwidth scanners running has to do with preventing a single bandwidth scanner from influencing the median. Even if there were 5 or 6 scanners, we'd require at least 3 scanner results before falling back to the relays' self-reported bandwidth.
Best, Karsten