That's our chart of backend sessions / sec for GitLab.com [1].
There's also a chart for frontend sessions [2], please keep in mind that there's a lot of CI / bot sessions on these dashboards. In addition to that there's much other interesting info on our HAProxy Grafana dashboard [3]. In case anyone's interested in even more metrics, there's a bunch of interesting dashboards on our Grafana instance [4].
From http://monitor.gitlab.net/dashboard/db/haproxy-stats?refresh...
But of course it is hard to mirror your repo to GitLab.com when GitHub.com is down, so maybe other sites are a better measure.