https://grafana.wikimedia.org/dashboard/db/varnish-http-erro... (and grafana.wikimedia.org in general) have more stats. It stated '13.38 Million req/min), which I think is ~230,000 req/s
Nice find!
https://ganglia.wikimedia.org/latest/stacked.php?m=ap_rps&c=...
which you can see is not showing any substantial increase due to the passing of Prince. The big hole of two days that ends just before the news broke is due to wikimedia switching traffic to a second datacenter for two days, see http://blog.wikimedia.org/2016/04/18/wikimedia-server-switch...