add benchmarks from Arthur

exporter/prometheusremotewriteexporter/exporter_test.go

@@ -5,10 +5,13 @@ package prometheusremotewriteexporter
 
 import (
 	"context"
+	"fmt"
 	"io"
 	"net/http"
 	"net/http/httptest"
 	"net/url"
+	"strconv"
+	"strings"
 	"sync"
 	"testing"
 	"time"
@@ -1177,3 +1180,60 @@ func TestRetries(t *testing.T) {
 		})
 	}
 }
+
+func BenchmarkExecute(b *testing.B) {
+	for _, numSample := range []int{100, 1000, 10000} {
+		b.Run(fmt.Sprintf("numSample=%d", numSample), func(b *testing.B) {
+			benchmarkExecute(b, numSample)
+		})
+	}
+}
+
+func benchmarkExecute(b *testing.B, numSample int) {
+	mockServer := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, _ *http.Request) {
+		w.WriteHeader(http.StatusOK)
+	}))
+	defer mockServer.Close()
+	endpointURL, err := url.Parse(mockServer.URL)
+	require.NoError(b, err)
+
+	// Create the prwExporter
+	exporter := &prwExporter{
+		endpointURL: endpointURL,
+		client:      http.DefaultClient,
+	}
+
+	generateSamples := func(n int) []prompb.Sample {
+		samples := make([]prompb.Sample, 0, n)
+		for i := 0; i < n; i++ {
+			samples = append(samples, prompb.Sample{
+				Timestamp: int64(i),
+				Value:     float64(i),
+			})
+		}
+		return samples
+	}
+
+	reqs := make([]*prompb.WriteRequest, 0, b.N)
+	const labelValue = "abcdefg'hijlmn234!@#$%^&*()_+~`\"{}[],./<>?hello0123hiOlá你好Dzieńdobry9Zd8ra765v4stvuyte"
+	for n := 0; n < b.N; n++ {
+		num := strings.Repeat(strconv.Itoa(n), 16)
+		req := &prompb.WriteRequest{
+			Timeseries: []prompb.TimeSeries{{
+				Samples: generateSamples(numSample),
+				Labels: []prompb.Label{
+					{Name: "__name__", Value: "test_metric"},
+					{Name: "test_label_name_" + num, Value: labelValue + num},
+				}}},
+		}
+		reqs = append(reqs, req)
+	}
+
+	ctx := context.Background()
+	b.ReportAllocs()
+	b.ResetTimer()
+	for _, req := range reqs {
+		err := exporter.execute(ctx, req)
+		require.NoError(b, err)
+	}
+}