RethinkDB Cluster Monitoring

Display RethinkDB cluster statistics in a live graph using Go, Socket.io, and Epoch.

Transcript

1. RethinkDB Cluster Monitoring
2. Ryan Paul RethinkDB Evangelist @segphault
4. RethinkDB 1.16 • Changefeeds • Cluster admin • System tables
5. Backend Go and RethinkDB
6. Watch cluster stats r.Db("rethinkdb").Table("stats").Changes()
7. "new_val": { "id": ["cluster"], "query_engine": { "client_connections": 10, "clients_active": 2, "queries_per_sec": 12.971126524000002, "read_docs_per_sec": 0, "written_docs_per_sec": 7.4114252490000005 } }
8. Watch cluster stats r.Db("rethinkdb").Table("stats"). Filter(r.Row.Field("id").AtIndex(0).Eq("cluster")). Changes()
9. server, _ := socketio.NewServer(nil) stats, _ := r.Db("rethinkdb").Table("stats"). Filter(r.Row.Field("id").AtIndex(0).Eq("cluster")). Changes().Run(conn) go func() { var change r.WriteChanges for stats.Next(&change) { server.BroadcastTo( "monitor", "stats", change.NewValue) } }() Pass changes to Socket.io
10. Frontend Epoch and Polymer
11. Epoch A realtime charting library for building high performance visualizations.
12. Plot data with Epoch function timestamp() { return (new Date).getTime() / 1000; } var chart = $("#chart").epoch({ type: "time.line", axes: ["left", "bottom"], data: [ {label: "Writes", values: [{time: timestamp(), y: 0}]}, {label: "Reads", values: [{time: timestamp(), y: 0}]} ] }); var socket = io.connect(); socket.on("stats", function(data) { cluster.stats = data.query_engine; chart.push([ {time: timestamp(), y: cluster.stats.written_docs_per_sec}, {time: timestamp(), y: cluster.stats.read_docs_per_sec} ]); });
13. Bonus IRC bot for issue notification
14. Initialize bot ircConf := irc.NewConfig("mybot") ircConf.Server = "localhost:6667" bot := irc.Client(ircConf) bot.HandleFunc("connected", func(conn *irc.Conn, line *irc.Line) { log.Println("Connected to IRC server") conn.Join("#mychannel") })
15. Attach changefeed type Issue struct { Description, Type string } issues, _ := r.Db("rethinkdb").Table("current_issues"). Filter(r.Row.Field("critical").Eq(true)). Changes().Field("new_val").Run(db) go func() { var issue Issue for issues.Next(&issue) { if issue.Type != "" { text := strings.Split(issue.Description, "\n")[0] message := fmt.Sprintf("(%s) %s", issue.Type, text) bot.Privmsg("#mychannel", message) } } }()
16. Resources • http://rethinkdb.com/blog/realtime-cluster-monitoring/ • https://github.com/rethinkdb/rethink-status/tree/go-backend • http://rethinkdb.com/docs/quickstart/ Questions?