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].
[1] - http://monitor.gitlab.net/dashboard/db/haproxy-stats?refresh...
[2] - http://monitor.gitlab.net/dashboard/db/haproxy-stats?refresh...
[3] - http://monitor.gitlab.net/dashboard/db/haproxy-stats
[4] - http://monitor.gitlab.net/?orgId=1