Add threaded parsing in statsd input plugin (#6922)

plugins/inputs/statsd/statsd.go

@@ -31,6 +31,8 @@ const (
 	defaultSeparator           = "_"
 	defaultAllowPendingMessage = 10000
 	MaxTCPConnections          = 250
+
+	parserGoRoutines = 5
 )
 
 // Statsd allows the importing of statsd and dogstatsd data.
@@ -398,12 +400,14 @@ func (s *Statsd) Start(ac telegraf.Accumulator) error {
 		}()
 	}
 
+	for i := 1; i <= parserGoRoutines; i++ {
 		// Start the line parser
 		s.wg.Add(1)
 		go func() {
 			defer s.wg.Done()
 			s.parser()
 		}()
+	}
 	s.Log.Infof("Started the statsd service on %q", s.ServiceAddress)
 	return nil
 }

plugins/inputs/statsd/statsd_test.go

@@ -2,19 +2,21 @@ package statsd
 
 import (
 	"fmt"
+	"github.com/influxdata/telegraf"
+	"github.com/influxdata/telegraf/internal"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 	"net"
+	"sync"
 	"testing"
 	"time"
 
-	"github.com/influxdata/telegraf"
-	"github.com/influxdata/telegraf/internal"
 	"github.com/influxdata/telegraf/testutil"
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
 )
 
 const (
 	testMsg         = "test.tcp.msg:100|c"
+	producerThreads = 10
 )
 
 func NewTestStatsd() *Statsd {
@@ -137,15 +139,30 @@ func BenchmarkUDP(b *testing.B) {
 		if err != nil {
 			panic(err)
 		}
-		for i := 0; i < 250000; i++ {
-			fmt.Fprintf(conn, testMsg)
+
+		var wg sync.WaitGroup
+		for i := 1; i <= producerThreads; i++ {
+			wg.Add(1)
+			go sendRequests(conn, &wg)
 		}
+		wg.Wait()
+
 		// wait for 250,000 metrics to get added to accumulator
+		for len(listener.in) > 0 {
+			fmt.Printf("Left in buffer: %v \n", len(listener.in))
 			time.Sleep(time.Millisecond)
+		}
 		listener.Stop()
 	}
 }
 
+func sendRequests(conn net.Conn, wg *sync.WaitGroup) {
+	defer wg.Done()
+	for i := 0; i < 25000; i++ {
+		fmt.Fprintf(conn, testMsg)
+	}
+}
+
 // benchmark how long it takes to accept & process 100,000 metrics:
 func BenchmarkTCP(b *testing.B) {
 	listener := Statsd{
@@ -169,11 +186,16 @@ func BenchmarkTCP(b *testing.B) {
 		if err != nil {
 			panic(err)
 		}
-		for i := 0; i < 250000; i++ {
-			fmt.Fprintf(conn, testMsg)
+		var wg sync.WaitGroup
+		for i := 1; i <= producerThreads; i++ {
+			wg.Add(1)
+			go sendRequests(conn, &wg)
 		}
+		wg.Wait()
 		// wait for 250,000 metrics to get added to accumulator
+		for len(listener.in) > 0 {
 			time.Sleep(time.Millisecond)
+		}
 		listener.Stop()
 	}
 }
@@ -1678,3 +1700,48 @@ func TestTCP(t *testing.T) {
 		testutil.IgnoreTime(),
 	)
 }
+
+func TestUdp(t *testing.T) {
+	statsd := Statsd{
+		Log:                    testutil.Logger{},
+		Protocol:               "udp",
+		ServiceAddress:         "localhost:8125",
+		AllowedPendingMessages: 250000,
+	}
+	var acc testutil.Accumulator
+	require.NoError(t, statsd.Start(&acc))
+	defer statsd.Stop()
+
+	conn, err := net.Dial("udp", "127.0.0.1:8125")
+	_, err = conn.Write([]byte("cpu.time_idle:42|c\n"))
+	require.NoError(t, err)
+	err = conn.Close()
+	require.NoError(t, err)
+
+	for {
+		err = statsd.Gather(&acc)
+		require.NoError(t, err)
+
+		if len(acc.Metrics) > 0 {
+			break
+		}
+	}
+
+	testutil.RequireMetricsEqual(t,
+		[]telegraf.Metric{
+			testutil.MustMetric(
+				"cpu_time_idle",
+				map[string]string{
+					"metric_type": "counter",
+				},
+				map[string]interface{}{
+					"value": 42,
+				},
+				time.Now(),
+				telegraf.Counter,
+			),
+		},
+		acc.GetTelegrafMetrics(),
+		testutil.IgnoreTime(),
+	)
+}