package main import ( "context" "fmt" "log" "math/rand" "net/http" "sync" "time" "github.com/libp2p/go-libp2p" "github.com/libp2p/go-libp2p/core/peer" "github.com/libp2p/go-libp2p/p2p/protocol/ping" "github.com/prometheus/client_golang/prometheus" "github.com/prometheus/client_golang/prometheus/promhttp" rcmgr "github.com/libp2p/go-libp2p/p2p/host/resource-manager" ) const ClientCount = 32 func main() { http.Handle("/metrics", promhttp.Handler()) go func() { http.Handle("/debug/metrics/prometheus", promhttp.Handler()) log.Fatal(http.ListenAndServe(":5001", nil)) }() rcmgr.MustRegisterWith(prometheus.DefaultRegisterer) str, err := rcmgr.NewStatsTraceReporter() if err != nil { log.Fatal(err) } rmgr, err := rcmgr.NewResourceManager(rcmgr.NewFixedLimiter(rcmgr.DefaultLimits.AutoScale()), rcmgr.WithTraceReporter(str)) if err != nil { log.Fatal(err) } server, err := libp2p.New(libp2p.ResourceManager(rmgr)) if err != nil { log.Fatal(err) } // Make a bunch of clients that all ping the server at various times wg := sync.WaitGroup{} for i := 0; i < ClientCount; i++ { wg.Add(1) go func(i int) { defer wg.Done() time.Sleep(time.Duration(i%100) * 100 * time.Millisecond) newClient(peer.AddrInfo{ ID: server.ID(), Addrs: server.Addrs(), }, i) }(i) } wg.Wait() } func newClient(serverInfo peer.AddrInfo, pings int) { // Sleep some random amount of time to spread out the clients so the graphs look more interesting time.Sleep(time.Duration(rand.Intn(100)) * time.Second) fmt.Println("Started client", pings) client, err := libp2p.New( // We just want metrics from the server libp2p.DisableMetrics(), libp2p.NoListenAddrs, ) defer func() { _ = client.Close() }() if err != nil { log.Fatal(err) } client.Connect(context.Background(), serverInfo) p := ping.Ping(context.Background(), client, serverInfo.ID) pingSoFar := 0 for pingSoFar < pings { res := <-p pingSoFar++ if res.Error != nil { log.Fatal(res.Error) } time.Sleep(5 * time.Second) } }