Java 가상쓰레드 속도 비교

목표

일반 thread 와 가상 thread 속도 비교하기(IO작업)

일반 thread 코드

import java.net.URI;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;
import java.time.Duration;
import java.time.Instant;
import java.util.concurrent.CompletableFuture;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;

public class PlatformThreadTest {
    public static void main(String[] args) throws Exception {
        var client = HttpClient.newHttpClient();
        var request = HttpRequest.newBuilder()
                .uri(new URI("http://localhost:4000/"))
                .build();

        int totalRequests = 100000;
        int batchSize = 100;
        int numBatches = totalRequests / batchSize;

        Instant start = Instant.now();

        for (int batch = 0; batch < numBatches; batch++) {
            var executor = Executors.newFixedThreadPool(batchSize);
            CompletableFuture<?>[] futures = new CompletableFuture<?>[batchSize];

            for (int i = 0; i < batchSize; i++) {
                futures[i] = CompletableFuture.runAsync(() -> {
                    try {
                        HttpResponse<String> response = client.send(request, HttpResponse.BodyHandlers.ofString());
                        // System.out.println("Response code: " + response.statusCode());
                    } catch (Exception e) {
                        e.printStackTrace();
                    }
                }, executor);
            }

            CompletableFuture.allOf(futures).join();
            executor.shutdown();
            executor.awaitTermination(1, TimeUnit.MINUTES);
        }

        Instant end = Instant.now();
        System.out.println("Time taken with platform threads: " + Duration.between(start, end).toMillis() + " ms");
    }
}

---

가상 thread 코드

import java.net.URI;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;
import java.time.Duration;
import java.time.Instant;
import java.util.concurrent.CompletableFuture;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;

public class VirtualThreadTest {
    public static void main(String[] args) throws Exception {
        var client = HttpClient.newHttpClient();
        var request = HttpRequest.newBuilder()
                .uri(new URI("http://localhost:4000/"))
                .build();

        int totalRequests = 100000;
        int batchSize = 100;
        int numBatches = totalRequests / batchSize;

        Instant start = Instant.now();

        for (int batch = 0; batch < numBatches; batch++) {
            var executor = Executors.newVirtualThreadPerTaskExecutor();
            CompletableFuture<?>[] futures = new CompletableFuture<?>[batchSize];

            for (int i = 0; i < batchSize; i++) {
                futures[i] = CompletableFuture.runAsync(() -> {
                    try {
                        HttpResponse<String> response = client.send(request, HttpResponse.BodyHandlers.ofString());
                        // System.out.println("Response code: " + response.statusCode());
                    } catch (Exception e) {
                        e.printStackTrace();
                    }
                }, executor);
            }

            CompletableFuture.allOf(futures).join();
            executor.shutdown();
            executor.awaitTermination(1, TimeUnit.MINUTES);
        }

        Instant end = Instant.now();
        System.out.println("Time taken with virtual threads: " + Duration.between(start, end).toMillis() + " ms");
    }
}

---

server 코드

const http = require('http');

const hostname = '127.0.0.1';
const port = 4000;

const server = http.createServer((req, res) => {
  res.statusCode = 200;
  res.setHeader('Content-Type', 'text/plain');
  res.end('Hello, World!\n');
});

server.listen(port, hostname, () => {
  console.log(`Server running at http://${hostname}:${port}/`);
});

---

• client 10만 request 결과
  • 일반 thread 12초
  • 가상 thread 6초

정리

---

일반, 가상 쓰레드로 각각 10만번 요청했을 때 6, 12초가 걸렸다.
cpu 연산에서는 차이가 없겠지만 IO 작업이 주 일때는 가상 쓰레드를 이용하자