Performance Comparison of Java FunTester, Go net/http, and fasthttp HTTP Servers

Test Cases

The previous post evaluated three HTTP client libraries (Java & Go) and concluded that fasthttp > FunTester > http in client performance. This article examines the server‑side performance of services built with those three frameworks.

The test plan measures QPS, CPU usage, and memory consumption of each server under different thread counts. Earlier Mac‑local HTTP service limits dropped after OS upgrades, so the focus is on comparative load testing rather than absolute limits.

Test Script

The test uses FunTester’s standard template com.funtester.frame.thread.RequestThreadTimes . The script (simplified) is shown below:

static String url = "http://localhost:8001/test";

public static void main(String[] args) {
    HttpGet httpGet = getHttpGet(url);
    RUNUP_TIME = 0;
    RequestThreadTimes requestThreadTimes = new RequestThreadTimes(httpGet, 20000);
    new Concurrent(requestThreadTimes, 20, "FunTester").start();
}

Thread count, warm‑up time, and request numbers are hard‑coded.

Server Implementations

All servers return the plain string "Have Fun ~ Tester !" as the response.

FunTester (Java)

Implemented with the moco_FunTester framework (a thin wrapper around mocoAPI). This framework previously achieved 120k QPS.

static void main(String[] args) {
    def server = getServerNoLog(8001)
    server.response("Have Fun ~ Tester !")
    def run = run(server)
    waitForKey("fan")
    run.stop()
}

Go net/http

A minimal Go HTTP server using the standard library:

func TestHttpSer2(t *testing.T) {
    http.Handle("/test", &indexHandler{content: "Have Fun ~ Tester !"})
    http.ListenAndServe(":8001", nil)
}

Go fasthttp

The same endpoint implemented with the fasthttp library and router:

func TestFastSer2(t *testing.T) {
    address := ":8001"

    router := fasthttprouter.New()
    router.GET("/test", func(ctx *fasthttp.RequestCtx) {
        ctx.Response.SetBody([]byte("Have Fun ~ Tester !"))
    })
    fasthttp.ListenAndServe(address, router.Handler)
}

Measured Results

1 Thread

Framework

CPU

Memory

QPS

FunTester

39.85

212.2 MB

17073

Go(net/http)

93.72

16.5 MB

14124

Go(/valyala/fasthttp)

61.53

12.8 MB

17502

5 Threads

Framework

CPU

Memory

QPS

FunTester

185.75

181.8 MB

64690

Go(net/http)

311.89

18.4 MB

48608

Go(/valyala/fasthttp)

186.85

15.1 MB

67001

10 Threads

Framework

CPU

Memory

QPS

FunTester

276.91

161.0 MB

75795

Go(net/http)

479.69

19.0 MB

62534

Go(/valyala/fasthttp)

269.33

16.6 MB

75723

Conclusion

Overall, the server‑side ranking matches the client‑side results: fasthttp > FunTester > net/http. Go’s net/http consumes more memory and CPU, resulting in slightly lower QPS. The superior performance of fasthttp stems from its object‑pool design, though developers should be aware of the associated pitfalls when using it in high‑throughput services.