add report merging benchmark

app/benchmark_internal_test.go

@@ -51,6 +51,22 @@ func BenchmarkReportUnmarshal(b *testing.B) {
 	}
 }
 
+func BenchmarkReportMerge(b *testing.B) {
+	reports, err := readReportFiles(*benchReportPath)
+	if err != nil {
+		b.Fatal(err)
+	}
+	merger := NewSmartMerger()
+
+	b.ReportAllocs()
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		b.StopTimer()
+		b.StartTimer()
+		merger.Merge(reports)
+	}
+}
+
 func BenchmarkTopologyList(b *testing.B) {
 	benchmarkRender(b, func(report report.Report) {
 		request := &http.Request{