网络基本概念和测试( 三 ) _网络

测试：
# -c表示并发请求数为1000，-n表示总的请求数为10000[root@localhost ~]#ab -c 1000 -n 10000 http://192.168.31.50/This is ApacheBench, Version 2.3 <$Revision: 1843412 $>Copyright 1996 Adam Twiss, Zeus Technology Ltd, http://www.zeustech.net/Licensed to The Apache Software Foundation, http://www.apache.org/Benchmarking 192.168.31.50 (be patient)apr_socket_recv: Connection reset by peer (104)Total of 223 requests completed[root@localhost ~]#直接报错，尴尬了，难道是队列不够设置下:
vim /etc/sysctl.confnet.ipv4.tcp_syncookies = 0net.ipv4.tcp_max_syn_backlog =1024# 生效：sysctl -p# 注意net.ipv4.tcp_syncookies设置为1的话，半连接队列没有用的

SYN Cookie 是对 TCP 服务器端的三次握手协议作一些修改，专门用来防范 SYN Flood 攻击的一种手段。它的原理是，在 TCP 服务器收到 TCP SYN 包并返回 TCP SYN+ACK 包时，不分配一个专门的数据区，而是根据这个 SYN 包计算出一个 cookie 值。在收到 TCP ACK 包时，TCP 服务器在根据那个 cookie 值检查这个 TCP ACK 包的合法性。如果合法，再分配专门的数据区进行处理未来的 TCP 连接。

结果还不行，抓包看下，都是直接对 80 端口发送 RST 报文，有点尴尬，没看到连接报文，后来查了下，可能是在接手 tcp_syncookies 报错，所以把报错继续发送选项打开，即加个-r 选项如下：

[root@localhost ~]#ab -r -c 1000 -n 10000 http://192.168.31.50/This is ApacheBench, Version 2.3 <$Revision: 1843412 $>Copyright 1996 Adam Twiss, Zeus Technology Ltd, http://www.zeustech.net/Licensed to The Apache Software Foundation, http://www.apache.org/Benchmarking 192.168.31.50 (be patient)Completed 1000 requestsCompleted 2000 requestsCompleted 3000 requestsCompleted 4000 requestsCompleted 5000 requestsCompleted 6000 requestsCompleted 7000 requestsCompleted 8000 requestsCompleted 9000 requestsCompleted 10000 requestsFinished 10000 requestsServer Software:nginx/1.15.4Server Hostname:192.168.31.50Server Port:80Document Path:/Document Length:153 bytesConcurrency Level:1000Time taken for tests:0.994 secondsComplete requests:10000Failed requests:0Non-2xx responses:10000Total transferred:3030000 byteshtml transferred:1530000 bytesRequests per second:10061.44 [#/sec] (mean)Time per request:99.389 [ms] (mean)Time per request:0.099 [ms] (mean, across all concurrent requests)Transfer rate:2977.16 [Kbytes/sec] receivedConnection Times (ms)minmean[+/-sd] medianmaxConnect:056.7239Processing:132 101.811851Waiting:131 101.810851Total:337 104.413870Percentage of the requests served within a certain time (ms)50%1366%1675%1980%2190%4495%8498%45399%858 100%870 (longest request)

关键输出信息：

1.每秒平均发送请求：Requests per second: 10061.44 [#/sec](mean)2.平均请求时延 Time per request: 99.389 [ms](mean)3.吞吐量： Transfer rate: 2977.16 [Kbytes/sec] received

3.4 应用层测试性能wrk、TCPCopy、Jmeter 或者 LoadRunner 等工具可以测试实际负载的。以 wrk 为例测试：
wget https://github.com.cnpmjs.org/wg/wrktar xvf wrk*cd wrk*makecp wrk /usr/local/bin测试：

# 测试 -t12 开始12个线程 -c400 保持400个http连接 -d30s 持续时间30s[root@localhost wrk-master]# wrk -t12 -c400 -d30s http://192.168.31.50/Running 30s test @ http://192.168.31.50/12 threads and 400 connectionsThread StatsAvgStdevMax+/- StdevLatency22.42ms17.12ms 564.75ms97.18%Req/Sec1.56k261.573.13k70.10%558047 requests in 30.04s, 163.89MB readNon-2xx or 3xx responses: 558047Requests/sec:18574.38Transfer/sec:5.46MB