func Run()

in systemtest/benchtest/main.go [166:254]
80 lines of code
21 McCabe index (conditional complexity)

func Run(allBenchmarks ...BenchmarkFunc) error {
	// Set flags in package testing.
	testing.Init()
	if err := flag.Set("test.benchtime", benchConfig.Benchtime.String()); err != nil {
		return err
	}
	// Sets the http.DefaultClient.Transport.TLSClientConfig.InsecureSkipVerify
	// to match the "-secure" flag value.
	verifyTLS := loadgencfg.Config.Secure
	http.DefaultClient.Transport = &http.Transport{
		TLSClientConfig: &tls.Config{InsecureSkipVerify: !verifyTLS},
	}
	os.Setenv("ELASTIC_APM_VERIFY_SERVER_CERT", fmt.Sprint(verifyTLS))
	var profiles profiles
	if err := profiles.init(); err != nil {
		return err
	}
	defer func() {
		if err := profiles.writeProfiles(); err != nil {
			log.Printf("failed to write profiles: %s", err)
		}
	}()

	matchRE := benchConfig.RunRE
	benchmarks := make([]benchmark, 0, len(allBenchmarks))
	for _, benchmarkFunc := range allBenchmarks {
		name, err := benchmarkFuncName(benchmarkFunc)
		if err != nil {
			return err
		}
		if matchRE == nil || matchRE.MatchString(name) {
			benchmarks = append(benchmarks, benchmark{
				name: name,
				f:    benchmarkFunc,
			})
		}
	}
	sort.Slice(benchmarks, func(i, j int) bool {
		return benchmarks[i].name < benchmarks[j].name
	})

	var maxLen int
	agentsList := benchConfig.AgentsList
	for _, agents := range agentsList {
		for _, benchmark := range benchmarks {
			if n := len(fullBenchmarkName(benchmark.name, agents)); n > maxLen {
				maxLen = n
			}
		}
	}

	// Warm up the APM Server with the specified `-agents`. Only the first
	// value in the list will be used.
	if len(agentsList) > 0 && benchConfig.WarmupTime.Seconds() > 0 {
		agents := agentsList[0]
		serverURL := loadgencfg.Config.ServerURL.String()
		secretToken := loadgencfg.Config.SecretToken
		if err := warmup(agents, benchConfig.WarmupTime, serverURL, secretToken); err != nil {
			return fmt.Errorf("warm-up failed with %d agents: %v", agents, err)
		}
	}

	for _, agents := range agentsList {
		runtime.GOMAXPROCS(int(agents))
		for _, benchmark := range benchmarks {
			name := fullBenchmarkName(benchmark.name, agents)
			for i := 0; i < int(benchConfig.Count); i++ {
				profileChan := profiles.record(name)
				result, failed, skipped, err := runBenchmark(benchmark.f)
				if err != nil {
					return err
				}
				if skipped {
					continue
				}
				if failed {
					fmt.Fprintf(os.Stderr, "--- FAIL: %s\n", name)
					return fmt.Errorf("benchmark %q failed", name)
				} else {
					fmt.Fprintf(os.Stderr, "%-*s\t%s\t%s\n", maxLen, name, result, result.MemString())
				}
				if err := <-profileChan; err != nil {
					return err
				}
			}
		}
	}
	return nil
}