Add new graph showing directory traffic as percentage of all traffic
Mike asked me a while ago to make a graph showing what fraction of network capacity is spent on directory traffic as an easy way to measure directory overhead. The idea was that this graph should trend down as we make directory fetches more efficient, but that it could trend up if we add a bunch of clients that don't do much other than download the consensus.
We already have two related graphs, Total relay bandwidth and Bandwidth spent on answering directory requests, and this new graph would basically combine those two.
I made a sample graph that I'll attach to this ticket together with the code to make that graph.
Let's use this ticket to discuss whether such a graph would be useful to have on Tor Metrics, and if so, let's use it to write a useful description and work on a metrics-web patch.