架构师训练营 - 命题作业 第 7 周
发布于: 2020 年 07 月 22 日
1. 性能压测的时候，随着并发压力的增加，系统响应时间和吞吐量如何变化，为什么？
响应时间在最佳运行区间略有上升；在负载测试区间逐渐上升；在压力测试区间迅速上升直至崩溃点。
吞吐量在最佳运行区间迅速上升；在负载测试区间缓慢上升；在压力测试区间下降直至崩溃点。
2. 用你熟悉的编程语言写一个 web 性能压测工具，输入参数：URL，请求总次数，并发数。输出参数：平均响应时间，95% 响应时间。用这个测试工具以 10 并发、100 次请求压测 www.baidu.com。
package test;
import java.util.concurrent.ConcurrentLinkedQueue;import java.util.concurrent.CountDownLatch;
import org.slf4j.Logger;import org.slf4j.LoggerFactory;
public class RequestThread implements Runnable { private static final Logger LOG = LoggerFactory.getLogger(RequestThread.class); private CountDownLatch countDownLatch; private String requestUrl; private ConcurrentLinkedQueue<Long> queue;
public RequestThread(String requestUrl, CountDownLatch countDownLatch, ConcurrentLinkedQueue<Long> queue) { this.requestUrl = requestUrl; this.countDownLatch = countDownLatch; this.queue = queue; }
public void run() { try { long startTime = System.currentTimeMillis(); boolean isSuccess = HttpClientUtil.get(requestUrl, null); if (!isSuccess) { LOG.error("response error.....threadName:" + Thread.currentThread().getName()); } long endTime = System.currentTimeMillis(); queue.add(endTime-startTime); countDownLatch.countDown(); } catch (Exception e) { LOG.error("requset error.....threadName:" + Thread.currentThread().getName()); }
}
}
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package test;
import java.io.IOException;import java.util.Arrays;import java.util.concurrent.ConcurrentLinkedQueue;import java.util.concurrent.CountDownLatch;import java.util.concurrent.ExecutorService;import java.util.concurrent.Executors;
public class StressTest { private Integer threadCount = 0; private String requestUrl = null; private Integer requestCount = 0; private ExecutorService ThreadPool = null; private ConcurrentLinkedQueue<Long> queue = null; public static void main(String[] args) throws Exception { System.out.println("start execute....."); StressTest st = new StressTest(); st.init(10,"http://www.baidu.com",100); st.exec(); st.printResult(); }
public void init(int threadCount, String requestUrl, int requestCount) throws IOException { this.threadCount = threadCount; this.requestCount = requestCount; this.requestUrl = requestUrl; ThreadPool = Executors.newFixedThreadPool(this.threadCount); queue = new ConcurrentLinkedQueue<Long> (); }
public void exec() throws InterruptedException { CountDownLatch requestCountDown = new CountDownLatch(requestCount); for (int i = 0; i < requestCount; i++) { RequestThread requestThread = new RequestThread(requestUrl, requestCountDown, queue); ThreadPool.execute(requestThread); } requestCountDown.await(); } public void printResult() { int size = queue.size(); Long[] times = new Long[size]; queue.toArray(times); Arrays.parallelSort(times); long time100 = 0; int size95 = (int)(times.length*0.95); long time95 = 0; for (int i = 0; i < times.length; i++) { if(i<size95) time95 += times[i]; time100 += times[i]; } System.out.println("平均响应时间(毫秒)："+ time100/size); System.out.println("95% 响应时间（毫秒）："+ time95/size95); }
}
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start execute.....平均响应时间：44895% 响应时间：312复制代码
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发布于: 2020 年 07 月 22 日阅读数: 35
版权声明: 本文为 InfoQ 作者【铁血杰克】的原创文章。
原文链接:【http://xie.infoq.cn/article/1610e49f790e95fb4b033608a】。未经作者许可，禁止转载。
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