Performance metrics documentation

Makefile

@@ -186,6 +186,10 @@ grafana/gdk-pg-created:
 	PATH=${postgres_bin_dir}:${PATH} support/create-grafana-db
 	touch $@
+performance-metrics-setup:	influxdb-setup grafana-setup Procfile
+	printf ',s/^#influxdb/influxdb/\nwq\n' | ed -s Procfile
+	printf ',s/^#grafana/grafana/\nwq\n' | ed -s Procfile
+
 clean-config:
 	rm -f \
 	gitlab/config/gitlab.yml \

README.md

@@ -655,6 +655,10 @@ Next make sure that HTTPS is enabled in gitlab/config/gitlab.yml.
 Uncomment the `workhorse-stunnel` line in your Procfile. Now `./run app`
 (and `./run`) will start stunnel listening on https://localhost:3443.
+## Performance metrics
+
+See [doc/performance_metrics.md](doc/performance_metrics.md).
+
 ## OS X, other developer OS's
 MR welcome!

doc/performance_metrics.md

+# Performance metrics for GitLab
+
+GitLab comes with a built-in performance metrics system. Metrics are
+collected by InfluxDB and visualized using Grafana.
+
+To use performance metrics in GitLab Development Kit you need a working
+Golang compiler and NPM installed. InfluxDB and Grafana consume about
+700MB of additional disk space (excluding metrics data).
+
+You need to have a working GDK installation before you install InfluxDB
+and Grafana.
+
+First make sure you do not have `./run` active anywhere. Then run:
+
+    rm Procfile
+    make performance-metrics-setup
+
+This will download and compile InfluxDB and Grafana from source; this
+takes a while.
+
+Next, go to http://localhost:3000/admin/application\_settings , look for
+the 'Metrics' section, and select 'Enable InfluxDB metrics'. InfluxDB is
+using the default host and port (localhost:8089).
+
+## Caveats
+
+InfluxDB uses several UDP and TCP ports in the 8080-8090 range. We set
+as many ports as possible to only listen on localhost but the cluster
+auto-discovery mechanism insists on binding to 0.0.0.0.
+
+It is currently not possible to have two separate GDK installations
+running on the same host (e.g. one for GitLab CE, one for GitLab EE) and
+enable InfluxDB+Grafana on both.

[username-removed-25949]

@jacobvosmaer this won't work.
The next command needs an existing Procfile. I get the follwing error otherwise: ERROR: Procfile does not exist.

[Jacob Vosmaer (GitLab)]

Thanks @haynes , this should be fixed in c9163294