在测试的过程中，需要模拟多线程通信，马上想到了Jmeter启动多线程去访问Web服务器实现，先简单验证一下
搭建web服务器
已有的CentOS7.2主机上，安装并设置好http服务
# yum install httpd -y
# vi /etc/httpd/conf/httpd.conf
Listen 80
DocumentRoot "/var/www/html"
[root@localhost html]# vi index.html
第一个静态文件
Hello world！
#
# service httpd start
安装Jmeter
在Windows/CentOS上安装Java8环境的说明网上一搜一大把，这里就不赘述了。下载好的apache-jmeter-5.0.zip在/var/www/html/下也放一份。作为HTTP要获取的文件。
Windows环境
解压缩apache-jmeter-5.0.zip，以管理员身份启动bin/jmeter.bat，正常情况下就能看到Jmeter的GUI。
设置一下语言
让log显示出来，设置log等级，帮助定位
已有的Test Plan下创建一个线程组
此例中5秒启动100个线程，就是每秒启动20个线程
线程组中添加一个HTTP请求,去获取zip文件
此时web服务器上
# pwd
/var/www/html
# ll
total 55624
-rwxr-xr-x. 1 wuli root 56952455 Dec 19 10:56 apache-jmeter-5.0.zip
-rwxr-xr-x. 1 wuli apache 154 Dec 19 09:09 index.html
#
也可以加一些其它的监控项
验证
在Windows的GUI上，可以将线程组的参数先改小并运行一下。无误后将当前设置保存为thread1.jmx文件，并放到Linux服务器上。
Jmeter是非常“吃资源”的，因此在实际性能测试的时候，应该使用CLI来运行。
命令执行如：jmeter -n -t xx.jmx -l jtl
常用参数解释如下：
-n：说明jmeter非GUI运行
-t：运行的测试计划名称，xxx.jmx路径+文件
-l：JTL文件去保存结果，路径+xxx.jtl
-r: 使用远程执行
-j：保存执行log
-H：代理机主机名或者ip地址
-P：代理机端口
例如：
# pwd
/root/apache-jmeter-5.0/bin
# ./jmeter.sh -n -t thread1.jmx -l abc.jtl
Dec 19, 2018 3:03:35 PM java.util.prefs.FileSystemPreferences$1 run
INFO: Created user preferences directory.
Creating summariser
Created the tree successfully using thread1.jmx
Starting the test @ Wed Dec 19 15:03:36 ULAT 2018 (1545203016678)
Waiting for possible Shutdown/StopTestNow/Heapdump message on port 4445
summary = 10 in 00:00:38 = 0.3/s Avg: 14141 Min: 794 Max: 32868 Err: 0 (0.00%)
Tidying up ... @ Wed Dec 19 15:04:16 ULAT 2018 (1545203056076)
... end of run
The JVM should have exited but did not.
The following non-daemon threads are still running (DestroyJavaVM is OK):
Thread[Thread-2,5,main], stackTrace:java.util.prefs.FileSystemPreferences#sync at line:718
java.util.prefs.FileSystemPreferences#flush at line:824
java.util.prefs.FileSystemPreferences#syncWorld at line:464
java.util.prefs.FileSystemPreferences#access$1200 at line:50
java.util.prefs.FileSystemPreferences$4$1#run at line:442
Thread[DestroyJavaVM,5,main], stackTrace:java.lang.Object#wait
java.lang.Thread#join at line:1252
java.lang.Thread#join at line:1326
java.lang.ApplicationShutdownHooks#runHooks at line:107
java.lang.ApplicationShutdownHooks$1#run at line:46
java.lang.Shutdown#runHooks at line:123
java.lang.Shutdown#sequence at line:167
java.lang.Shutdown#shutdown at line:234
#
查看运行结果
# cat abc.jtl
timeStamp,elapsed,label,responseCode,responseMessage,threadName,dataType,success,failureMessage,bytes,sentBytes,grpThreads,allThreads,URL,Latency,IdleTime,Connect
1545203017967,794,HTTP请求,200,OK,线程组 1-1,text,true,,56952754,138,2,2,http://10.25.130.254/apache-jmeter-5.0.zip,65,0,46
1545203018290,1991,HTTP请求,200,OK,线程组 1-2,text,true,,56952754,138,2,2,http://10.25.130.254/apache-jmeter-5.0.zip,21,0,14
1545203018778,9388,HTTP请求,200,OK,线程组 1-3,text,true,,56952754,138,8,8,http://10.25.130.254/apache-jmeter-5.0.zip,17,0,2
1545203021031,27041,HTTP请求,200,OK,线程组 1-6,text,true,,56952754,138,7,7,http://10.25.130.254/apache-jmeter-5.0.zip,7043,0,1
1545203021042,31843,HTTP请求,200,OK,线程组 1-7,text,true,,56952754,138,7,7,http://10.25.130.254/apache-jmeter-5.0.zip,7025,0,4
1545203021041,32867,HTTP请求,200,OK,线程组 1-4,text,true,,56952754,138,5,5,http://10.25.130.254/apache-jmeter-5.0.zip,7010,0,5
1545203021043,32868,HTTP请求,200,OK,线程组 1-5,text,true,,56952754,138,4,4,http://10.25.130.254/apache-jmeter-5.0.zip,7040,0,2
1545203053901,1309,HTTP请求,200,OK,线程组 1-8,text,true,,56952754,138,3,3,http://10.25.130.254/apache-jmeter-5.0.zip,224,0,5
1545203053267,1973,HTTP请求,200,OK,线程组 1-9,text,true,,56952754,138,2,2,http://10.25.130.254/apache-jmeter-5.0.zip,852,0,632
1545203053903,1345,HTTP请求,200,OK,线程组 1-10,text,true,,56952754,138,1,1,http://10.25.130.254/apache-jmeter-5.0.zip,274,0,2
#